From b262518262f5a13978eb2b17574a70411908e665 Mon Sep 17 00:00:00 2001
From: Konrad Dybcio <konrad.dybcio@linaro.org>
Date: Wed, 27 Mar 2024 19:24:49 +0100
Subject: PCI: dwc: Use msleep() in dw_pcie_wait_for_link()
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

According to [1], msleep should be used for large sleeps, such as the
100-ish ms one in this function. Comply with the guide and use it.

[1] https://docs.kernel.org/timers/timers-howto.html

[kwilczynski: commit log]
Link: https://lore.kernel.org/linux-pci/20240215-topic-pci_sleep-v2-1-79334884546b@linaro.org
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/pci/controller/dwc/pcie-designware.c | 2 +-
 drivers/pci/controller/dwc/pcie-designware.h | 3 +--
 2 files changed, 2 insertions(+), 3 deletions(-)

(limited to 'drivers/pci')

diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index 250cf7f40b85..62915e4b2ebd 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -655,7 +655,7 @@ int dw_pcie_wait_for_link(struct dw_pcie *pci)
 		if (dw_pcie_link_up(pci))
 			break;
 
-		usleep_range(LINK_WAIT_USLEEP_MIN, LINK_WAIT_USLEEP_MAX);
+		msleep(LINK_WAIT_SLEEP_MS);
 	}
 
 	if (retries >= LINK_WAIT_MAX_RETRIES) {
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index f8e5431a207b..0e8d46725497 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -63,8 +63,7 @@
 
 /* Parameters for the waiting for link up routine */
 #define LINK_WAIT_MAX_RETRIES		10
-#define LINK_WAIT_USLEEP_MIN		90000
-#define LINK_WAIT_USLEEP_MAX		100000
+#define LINK_WAIT_SLEEP_MS		90
 
 /* Parameters for the waiting for iATU enabled routine */
 #define LINK_WAIT_MAX_IATU_RETRIES	5
-- 
cgit v1.2.3-70-g09d2


From c2a57ee0f2f1ad8c970ff58b78a43e85abbdeb7f Mon Sep 17 00:00:00 2001
From: Frank Li <Frank.Li@nxp.com>
Date: Fri, 12 Apr 2024 12:08:41 -0400
Subject: PCI: dwc: Fix index 0 incorrectly being interpreted as a free ATU
 slot
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

When PERST# assert and deassert happens on the PERST# supported platforms,
both iATU0 and iATU6 will map inbound window to BAR0. DMA will access the
area that was previously allocated (iATU0) for BAR0, instead of the new
area (iATU6) for BAR0.

Right now, this isn't an issue because both iATU0 and iATU6 should
translate inbound accesses to BAR0 to the same allocated memory area.
However, having two separate inbound mappings for the same BAR is a
disaster waiting to happen.

The mappings between PCI BAR and iATU inbound window are maintained in the
dw_pcie_ep::bar_to_atu[] array. While allocating a new inbound iATU map for
a BAR, dw_pcie_ep_inbound_atu() API checks for the availability of the
existing mapping in the array and if it is not found (i.e., value in the
array indexed by the BAR is found to be 0), it allocates a new map value
using find_first_zero_bit().

The issue is the existing logic failed to consider the fact that the map
value '0' is a valid value for BAR0, so find_first_zero_bit() will return
'0' as the map value for BAR0 (note that it returns the first zero bit
position).

Due to this, when PERST# assert + deassert happens on the PERST# supported
platforms, the inbound window allocation restarts from BAR0 and the
existing logic to find the BAR mapping will return '6' for BAR0 instead of
'0' due to the fact that it considers '0' as an invalid map value.

Fix this issue by always incrementing the map value before assigning to
bar_to_atu[] array and then decrementing it while fetching. This will make
sure that the map value '0' always represents the invalid mapping."

Fixes: 4284c88fff0e ("PCI: designware-ep: Allow pci_epc_set_bar() update inbound map address")
Closes: https://lore.kernel.org/linux-pci/ZXsRp+Lzg3x%2Fnhk3@x1-carbon/
Link: https://lore.kernel.org/linux-pci/20240412160841.925927-1-Frank.Li@nxp.com
Reported-by: Niklas Cassel <Niklas.Cassel@wdc.com>
Tested-by: Niklas Cassel <niklas.cassel@wdc.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Niklas Cassel <niklas.cassel@wdc.com>
---
 drivers/pci/controller/dwc/pcie-designware-ep.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

(limited to 'drivers/pci')

diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index 2063cf2049e5..caa048761141 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -161,7 +161,7 @@ static int dw_pcie_ep_inbound_atu(struct dw_pcie_ep *ep, u8 func_no, int type,
 	if (!ep->bar_to_atu[bar])
 		free_win = find_first_zero_bit(ep->ib_window_map, pci->num_ib_windows);
 	else
-		free_win = ep->bar_to_atu[bar];
+		free_win = ep->bar_to_atu[bar] - 1;
 
 	if (free_win >= pci->num_ib_windows) {
 		dev_err(pci->dev, "No free inbound window\n");
@@ -175,7 +175,11 @@ static int dw_pcie_ep_inbound_atu(struct dw_pcie_ep *ep, u8 func_no, int type,
 		return ret;
 	}
 
-	ep->bar_to_atu[bar] = free_win;
+	/*
+	 * Always increment free_win before assignment, since value 0 is used to identify
+	 * unallocated mapping.
+	 */
+	ep->bar_to_atu[bar] = free_win + 1;
 	set_bit(free_win, ep->ib_window_map);
 
 	return 0;
@@ -212,7 +216,10 @@ static void dw_pcie_ep_clear_bar(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
 	struct dw_pcie_ep *ep = epc_get_drvdata(epc);
 	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
 	enum pci_barno bar = epf_bar->barno;
-	u32 atu_index = ep->bar_to_atu[bar];
+	u32 atu_index = ep->bar_to_atu[bar] - 1;
+
+	if (!ep->bar_to_atu[bar])
+		return;
 
 	__dw_pcie_ep_reset_bar(pci, func_no, bar, epf_bar->flags);
 
-- 
cgit v1.2.3-70-g09d2


From aa85ef61d841dc5506861f71c28c351e17a9f472 Mon Sep 17 00:00:00 2001
From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Date: Thu, 18 Apr 2024 12:04:25 -0400
Subject: PCI: dwc: Consolidate args of dw_pcie_prog_outbound_atu() into a
 structure
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

This is a preparation before adding the Msg-type outbound iATU
mapping. The respective update will require two more arguments added
to __dw_pcie_prog_outbound_atu(). That will make the already
complicated function prototype even more hard to comprehend accepting
_eight_ arguments.

To prevent that and keep the code more-or-less readable, move all the
outbound iATU-related arguments to a new config structure: struct
dw_pcie_ob_atu_cfg, and pass a pointer to dw_pcie_prog_outbound_atu(). The
structure should be locally defined and populated with the outbound iATU
settings implied by the caller context.

As a result of this change there is no longer need in having the two
distinctive methods for the Host and Endpoint outbound iATU setups since
the code can directly call the dw_pcie_prog_outbound_atu() method with the
config structure populated, so drop dw_pcie_prog_ep_outbound_atu().

[kwilczynski: commit log]
Link: https://lore.kernel.org/linux-pci/20240418-pme_msg-v8-2-a54265c39742@nxp.com
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
---
 drivers/pci/controller/dwc/pcie-designware-ep.c   | 21 +++++----
 drivers/pci/controller/dwc/pcie-designware-host.c | 52 ++++++++++++++++-------
 drivers/pci/controller/dwc/pcie-designware.c      | 49 ++++++++-------------
 drivers/pci/controller/dwc/pcie-designware.h      | 15 +++++--
 4 files changed, 77 insertions(+), 60 deletions(-)

(limited to 'drivers/pci')

diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index caa048761141..51571da24601 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -185,9 +185,8 @@ static int dw_pcie_ep_inbound_atu(struct dw_pcie_ep *ep, u8 func_no, int type,
 	return 0;
 }
 
-static int dw_pcie_ep_outbound_atu(struct dw_pcie_ep *ep, u8 func_no,
-				   phys_addr_t phys_addr,
-				   u64 pci_addr, size_t size)
+static int dw_pcie_ep_outbound_atu(struct dw_pcie_ep *ep,
+				   struct dw_pcie_ob_atu_cfg *atu)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
 	u32 free_win;
@@ -199,13 +198,13 @@ static int dw_pcie_ep_outbound_atu(struct dw_pcie_ep *ep, u8 func_no,
 		return -EINVAL;
 	}
 
-	ret = dw_pcie_prog_ep_outbound_atu(pci, func_no, free_win, PCIE_ATU_TYPE_MEM,
-					   phys_addr, pci_addr, size);
+	atu->index = free_win;
+	ret = dw_pcie_prog_outbound_atu(pci, atu);
 	if (ret)
 		return ret;
 
 	set_bit(free_win, ep->ob_window_map);
-	ep->outbound_addr[free_win] = phys_addr;
+	ep->outbound_addr[free_win] = atu->cpu_addr;
 
 	return 0;
 }
@@ -308,8 +307,14 @@ static int dw_pcie_ep_map_addr(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
 	int ret;
 	struct dw_pcie_ep *ep = epc_get_drvdata(epc);
 	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
-
-	ret = dw_pcie_ep_outbound_atu(ep, func_no, addr, pci_addr, size);
+	struct dw_pcie_ob_atu_cfg atu = { 0 };
+
+	atu.func_no = func_no;
+	atu.type = PCIE_ATU_TYPE_MEM;
+	atu.cpu_addr = addr;
+	atu.pci_addr = pci_addr;
+	atu.size = size;
+	ret = dw_pcie_ep_outbound_atu(ep, &atu);
 	if (ret) {
 		dev_err(pci->dev, "Failed to enable address\n");
 		return ret;
diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index d15a5c2d5b48..3a9cb4be22ab 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -554,6 +554,7 @@ static void __iomem *dw_pcie_other_conf_map_bus(struct pci_bus *bus,
 {
 	struct dw_pcie_rp *pp = bus->sysdata;
 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+	struct dw_pcie_ob_atu_cfg atu = { 0 };
 	int type, ret;
 	u32 busdev;
 
@@ -576,8 +577,12 @@ static void __iomem *dw_pcie_other_conf_map_bus(struct pci_bus *bus,
 	else
 		type = PCIE_ATU_TYPE_CFG1;
 
-	ret = dw_pcie_prog_outbound_atu(pci, 0, type, pp->cfg0_base, busdev,
-					pp->cfg0_size);
+	atu.type = type;
+	atu.cpu_addr = pp->cfg0_base;
+	atu.pci_addr = busdev;
+	atu.size = pp->cfg0_size;
+
+	ret = dw_pcie_prog_outbound_atu(pci, &atu);
 	if (ret)
 		return NULL;
 
@@ -589,6 +594,7 @@ static int dw_pcie_rd_other_conf(struct pci_bus *bus, unsigned int devfn,
 {
 	struct dw_pcie_rp *pp = bus->sysdata;
 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+	struct dw_pcie_ob_atu_cfg atu = { 0 };
 	int ret;
 
 	ret = pci_generic_config_read(bus, devfn, where, size, val);
@@ -596,9 +602,12 @@ static int dw_pcie_rd_other_conf(struct pci_bus *bus, unsigned int devfn,
 		return ret;
 
 	if (pp->cfg0_io_shared) {
-		ret = dw_pcie_prog_outbound_atu(pci, 0, PCIE_ATU_TYPE_IO,
-						pp->io_base, pp->io_bus_addr,
-						pp->io_size);
+		atu.type = PCIE_ATU_TYPE_IO;
+		atu.cpu_addr = pp->io_base;
+		atu.pci_addr = pp->io_bus_addr;
+		atu.size = pp->io_size;
+
+		ret = dw_pcie_prog_outbound_atu(pci, &atu);
 		if (ret)
 			return PCIBIOS_SET_FAILED;
 	}
@@ -611,6 +620,7 @@ static int dw_pcie_wr_other_conf(struct pci_bus *bus, unsigned int devfn,
 {
 	struct dw_pcie_rp *pp = bus->sysdata;
 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+	struct dw_pcie_ob_atu_cfg atu = { 0 };
 	int ret;
 
 	ret = pci_generic_config_write(bus, devfn, where, size, val);
@@ -618,9 +628,12 @@ static int dw_pcie_wr_other_conf(struct pci_bus *bus, unsigned int devfn,
 		return ret;
 
 	if (pp->cfg0_io_shared) {
-		ret = dw_pcie_prog_outbound_atu(pci, 0, PCIE_ATU_TYPE_IO,
-						pp->io_base, pp->io_bus_addr,
-						pp->io_size);
+		atu.type = PCIE_ATU_TYPE_IO;
+		atu.cpu_addr = pp->io_base;
+		atu.pci_addr = pp->io_bus_addr;
+		atu.size = pp->io_size;
+
+		ret = dw_pcie_prog_outbound_atu(pci, &atu);
 		if (ret)
 			return PCIBIOS_SET_FAILED;
 	}
@@ -655,6 +668,7 @@ static struct pci_ops dw_pcie_ops = {
 static int dw_pcie_iatu_setup(struct dw_pcie_rp *pp)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+	struct dw_pcie_ob_atu_cfg atu = { 0 };
 	struct resource_entry *entry;
 	int i, ret;
 
@@ -682,10 +696,13 @@ static int dw_pcie_iatu_setup(struct dw_pcie_rp *pp)
 		if (pci->num_ob_windows <= ++i)
 			break;
 
-		ret = dw_pcie_prog_outbound_atu(pci, i, PCIE_ATU_TYPE_MEM,
-						entry->res->start,
-						entry->res->start - entry->offset,
-						resource_size(entry->res));
+		atu.index = i;
+		atu.type = PCIE_ATU_TYPE_MEM;
+		atu.cpu_addr = entry->res->start;
+		atu.pci_addr = entry->res->start - entry->offset;
+		atu.size = resource_size(entry->res);
+
+		ret = dw_pcie_prog_outbound_atu(pci, &atu);
 		if (ret) {
 			dev_err(pci->dev, "Failed to set MEM range %pr\n",
 				entry->res);
@@ -695,10 +712,13 @@ static int dw_pcie_iatu_setup(struct dw_pcie_rp *pp)
 
 	if (pp->io_size) {
 		if (pci->num_ob_windows > ++i) {
-			ret = dw_pcie_prog_outbound_atu(pci, i, PCIE_ATU_TYPE_IO,
-							pp->io_base,
-							pp->io_bus_addr,
-							pp->io_size);
+			atu.index = i;
+			atu.type = PCIE_ATU_TYPE_IO;
+			atu.cpu_addr = pp->io_base;
+			atu.pci_addr = pp->io_bus_addr;
+			atu.size = pp->io_size;
+
+			ret = dw_pcie_prog_outbound_atu(pci, &atu);
 			if (ret) {
 				dev_err(pci->dev, "Failed to set IO range %pr\n",
 					entry->res);
diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index 62915e4b2ebd..b5df76693ccd 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -465,56 +465,56 @@ static inline u32 dw_pcie_enable_ecrc(u32 val)
 	return val | PCIE_ATU_TD;
 }
 
-static int __dw_pcie_prog_outbound_atu(struct dw_pcie *pci, u8 func_no,
-				       int index, int type, u64 cpu_addr,
-				       u64 pci_addr, u64 size)
+int dw_pcie_prog_outbound_atu(struct dw_pcie *pci,
+			      const struct dw_pcie_ob_atu_cfg *atu)
 {
+	u64 cpu_addr = atu->cpu_addr;
 	u32 retries, val;
 	u64 limit_addr;
 
 	if (pci->ops && pci->ops->cpu_addr_fixup)
 		cpu_addr = pci->ops->cpu_addr_fixup(pci, cpu_addr);
 
-	limit_addr = cpu_addr + size - 1;
+	limit_addr = cpu_addr + atu->size - 1;
 
 	if ((limit_addr & ~pci->region_limit) != (cpu_addr & ~pci->region_limit) ||
 	    !IS_ALIGNED(cpu_addr, pci->region_align) ||
-	    !IS_ALIGNED(pci_addr, pci->region_align) || !size) {
+	    !IS_ALIGNED(atu->pci_addr, pci->region_align) || !atu->size) {
 		return -EINVAL;
 	}
 
-	dw_pcie_writel_atu_ob(pci, index, PCIE_ATU_LOWER_BASE,
+	dw_pcie_writel_atu_ob(pci, atu->index, PCIE_ATU_LOWER_BASE,
 			      lower_32_bits(cpu_addr));
-	dw_pcie_writel_atu_ob(pci, index, PCIE_ATU_UPPER_BASE,
+	dw_pcie_writel_atu_ob(pci, atu->index, PCIE_ATU_UPPER_BASE,
 			      upper_32_bits(cpu_addr));
 
-	dw_pcie_writel_atu_ob(pci, index, PCIE_ATU_LIMIT,
+	dw_pcie_writel_atu_ob(pci, atu->index, PCIE_ATU_LIMIT,
 			      lower_32_bits(limit_addr));
 	if (dw_pcie_ver_is_ge(pci, 460A))
-		dw_pcie_writel_atu_ob(pci, index, PCIE_ATU_UPPER_LIMIT,
+		dw_pcie_writel_atu_ob(pci, atu->index, PCIE_ATU_UPPER_LIMIT,
 				      upper_32_bits(limit_addr));
 
-	dw_pcie_writel_atu_ob(pci, index, PCIE_ATU_LOWER_TARGET,
-			      lower_32_bits(pci_addr));
-	dw_pcie_writel_atu_ob(pci, index, PCIE_ATU_UPPER_TARGET,
-			      upper_32_bits(pci_addr));
+	dw_pcie_writel_atu_ob(pci, atu->index, PCIE_ATU_LOWER_TARGET,
+			      lower_32_bits(atu->pci_addr));
+	dw_pcie_writel_atu_ob(pci, atu->index, PCIE_ATU_UPPER_TARGET,
+			      upper_32_bits(atu->pci_addr));
 
-	val = type | PCIE_ATU_FUNC_NUM(func_no);
+	val = atu->type | PCIE_ATU_FUNC_NUM(atu->func_no);
 	if (upper_32_bits(limit_addr) > upper_32_bits(cpu_addr) &&
 	    dw_pcie_ver_is_ge(pci, 460A))
 		val |= PCIE_ATU_INCREASE_REGION_SIZE;
 	if (dw_pcie_ver_is(pci, 490A))
 		val = dw_pcie_enable_ecrc(val);
-	dw_pcie_writel_atu_ob(pci, index, PCIE_ATU_REGION_CTRL1, val);
+	dw_pcie_writel_atu_ob(pci, atu->index, PCIE_ATU_REGION_CTRL1, val);
 
-	dw_pcie_writel_atu_ob(pci, index, PCIE_ATU_REGION_CTRL2, PCIE_ATU_ENABLE);
+	dw_pcie_writel_atu_ob(pci, atu->index, PCIE_ATU_REGION_CTRL2, PCIE_ATU_ENABLE);
 
 	/*
 	 * Make sure ATU enable takes effect before any subsequent config
 	 * and I/O accesses.
 	 */
 	for (retries = 0; retries < LINK_WAIT_MAX_IATU_RETRIES; retries++) {
-		val = dw_pcie_readl_atu_ob(pci, index, PCIE_ATU_REGION_CTRL2);
+		val = dw_pcie_readl_atu_ob(pci, atu->index, PCIE_ATU_REGION_CTRL2);
 		if (val & PCIE_ATU_ENABLE)
 			return 0;
 
@@ -526,21 +526,6 @@ static int __dw_pcie_prog_outbound_atu(struct dw_pcie *pci, u8 func_no,
 	return -ETIMEDOUT;
 }
 
-int dw_pcie_prog_outbound_atu(struct dw_pcie *pci, int index, int type,
-			      u64 cpu_addr, u64 pci_addr, u64 size)
-{
-	return __dw_pcie_prog_outbound_atu(pci, 0, index, type,
-					   cpu_addr, pci_addr, size);
-}
-
-int dw_pcie_prog_ep_outbound_atu(struct dw_pcie *pci, u8 func_no, int index,
-				 int type, u64 cpu_addr, u64 pci_addr,
-				 u64 size)
-{
-	return __dw_pcie_prog_outbound_atu(pci, func_no, index, type,
-					   cpu_addr, pci_addr, size);
-}
-
 static inline u32 dw_pcie_readl_atu_ib(struct dw_pcie *pci, u32 index, u32 reg)
 {
 	return dw_pcie_readl_atu(pci, PCIE_ATU_REGION_DIR_IB, index, reg);
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 0e8d46725497..3d728953435b 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -298,6 +298,15 @@ enum dw_pcie_ltssm {
 	DW_PCIE_LTSSM_UNKNOWN = 0xFFFFFFFF,
 };
 
+struct dw_pcie_ob_atu_cfg {
+	int index;
+	int type;
+	u8 func_no;
+	u64 cpu_addr;
+	u64 pci_addr;
+	u64 size;
+};
+
 struct dw_pcie_host_ops {
 	int (*init)(struct dw_pcie_rp *pp);
 	void (*deinit)(struct dw_pcie_rp *pp);
@@ -432,10 +441,8 @@ void dw_pcie_write_dbi2(struct dw_pcie *pci, u32 reg, size_t size, u32 val);
 int dw_pcie_link_up(struct dw_pcie *pci);
 void dw_pcie_upconfig_setup(struct dw_pcie *pci);
 int dw_pcie_wait_for_link(struct dw_pcie *pci);
-int dw_pcie_prog_outbound_atu(struct dw_pcie *pci, int index, int type,
-			      u64 cpu_addr, u64 pci_addr, u64 size);
-int dw_pcie_prog_ep_outbound_atu(struct dw_pcie *pci, u8 func_no, int index,
-				 int type, u64 cpu_addr, u64 pci_addr, u64 size);
+int dw_pcie_prog_outbound_atu(struct dw_pcie *pci,
+			      const struct dw_pcie_ob_atu_cfg *atu);
 int dw_pcie_prog_inbound_atu(struct dw_pcie *pci, int index, int type,
 			     u64 cpu_addr, u64 pci_addr, u64 size);
 int dw_pcie_prog_ep_inbound_atu(struct dw_pcie *pci, u8 func_no, int index,
-- 
cgit v1.2.3-70-g09d2


From cd02e4b684fd3244bd55425e683e26a4003a2925 Mon Sep 17 00:00:00 2001
From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Date: Thu, 18 Apr 2024 12:04:26 -0400
Subject: PCI: dwc: Add outbound MSG TLPs support
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Add "code" and "routing" into struct dw_pcie_ob_atu_cfg for triggering
INTx IRQs by iATU in the PCIe endpoint mode in near the future.
PCIE_ATU_INHIBIT_PAYLOAD is set to issue TLP type of Msg instead of
MsgD. This implementation supports the data-less messages only for now.

Link: https://lore.kernel.org/linux-pci/20240418-pme_msg-v8-3-a54265c39742@nxp.com
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
---
 drivers/pci/controller/dwc/pcie-designware.c | 9 +++++++--
 drivers/pci/controller/dwc/pcie-designware.h | 4 ++++
 2 files changed, 11 insertions(+), 2 deletions(-)

(limited to 'drivers/pci')

diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index b5df76693ccd..26ecf0472f86 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -499,7 +499,7 @@ int dw_pcie_prog_outbound_atu(struct dw_pcie *pci,
 	dw_pcie_writel_atu_ob(pci, atu->index, PCIE_ATU_UPPER_TARGET,
 			      upper_32_bits(atu->pci_addr));
 
-	val = atu->type | PCIE_ATU_FUNC_NUM(atu->func_no);
+	val = atu->type | atu->routing | PCIE_ATU_FUNC_NUM(atu->func_no);
 	if (upper_32_bits(limit_addr) > upper_32_bits(cpu_addr) &&
 	    dw_pcie_ver_is_ge(pci, 460A))
 		val |= PCIE_ATU_INCREASE_REGION_SIZE;
@@ -507,7 +507,12 @@ int dw_pcie_prog_outbound_atu(struct dw_pcie *pci,
 		val = dw_pcie_enable_ecrc(val);
 	dw_pcie_writel_atu_ob(pci, atu->index, PCIE_ATU_REGION_CTRL1, val);
 
-	dw_pcie_writel_atu_ob(pci, atu->index, PCIE_ATU_REGION_CTRL2, PCIE_ATU_ENABLE);
+	val = PCIE_ATU_ENABLE;
+	if (atu->type == PCIE_ATU_TYPE_MSG) {
+		/* The data-less messages only for now */
+		val |= PCIE_ATU_INHIBIT_PAYLOAD | atu->code;
+	}
+	dw_pcie_writel_atu_ob(pci, atu->index, PCIE_ATU_REGION_CTRL2, val);
 
 	/*
 	 * Make sure ATU enable takes effect before any subsequent config
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 3d728953435b..4a3973935979 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -147,11 +147,13 @@
 #define PCIE_ATU_TYPE_IO		0x2
 #define PCIE_ATU_TYPE_CFG0		0x4
 #define PCIE_ATU_TYPE_CFG1		0x5
+#define PCIE_ATU_TYPE_MSG		0x10
 #define PCIE_ATU_TD			BIT(8)
 #define PCIE_ATU_FUNC_NUM(pf)           ((pf) << 20)
 #define PCIE_ATU_REGION_CTRL2		0x004
 #define PCIE_ATU_ENABLE			BIT(31)
 #define PCIE_ATU_BAR_MODE_ENABLE	BIT(30)
+#define PCIE_ATU_INHIBIT_PAYLOAD	BIT(22)
 #define PCIE_ATU_FUNC_NUM_MATCH_EN      BIT(19)
 #define PCIE_ATU_LOWER_BASE		0x008
 #define PCIE_ATU_UPPER_BASE		0x00C
@@ -302,6 +304,8 @@ struct dw_pcie_ob_atu_cfg {
 	int index;
 	int type;
 	u8 func_no;
+	u8 code;
+	u8 routing;
 	u64 cpu_addr;
 	u64 pci_addr;
 	u64 size;
-- 
cgit v1.2.3-70-g09d2


From 95cb8ff68851ed0d249fb8a1d9657987cd844e08 Mon Sep 17 00:00:00 2001
From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Date: Thu, 18 Apr 2024 12:04:24 -0400
Subject: PCI: Add PCIE_MSG_CODE_ASSERT_INTx message macros
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Add "Message Routing" and "INTx Mechanism Messages" macros to enable
a PCIe driver to send messages for INTx Interrupt Signaling.

Values from PCIe r6.1, sec 2.2.8 and 2.2.8.1.

Link: https://lore.kernel.org/linux-pci/20240418-pme_msg-v8-1-a54265c39742@nxp.com
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
---
 drivers/pci/pci.h | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

(limited to 'drivers/pci')

diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index fd44565c4756..95c95d981241 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -22,6 +22,24 @@
  */
 #define PCIE_PME_TO_L2_TIMEOUT_US	10000
 
+/* Message Routing (r[2:0]); PCIe r6.0, sec 2.2.8 */
+#define PCIE_MSG_TYPE_R_RC	0
+#define PCIE_MSG_TYPE_R_ADDR	1
+#define PCIE_MSG_TYPE_R_ID	2
+#define PCIE_MSG_TYPE_R_BC	3
+#define PCIE_MSG_TYPE_R_LOCAL	4
+#define PCIE_MSG_TYPE_R_GATHER	5
+
+/* INTx Mechanism Messages; PCIe r6.0, sec 2.2.8.1 */
+#define PCIE_MSG_CODE_ASSERT_INTA	0x20
+#define PCIE_MSG_CODE_ASSERT_INTB	0x21
+#define PCIE_MSG_CODE_ASSERT_INTC	0x22
+#define PCIE_MSG_CODE_ASSERT_INTD	0x23
+#define PCIE_MSG_CODE_DEASSERT_INTA	0x24
+#define PCIE_MSG_CODE_DEASSERT_INTB	0x25
+#define PCIE_MSG_CODE_DEASSERT_INTC	0x26
+#define PCIE_MSG_CODE_DEASSERT_INTD	0x27
+
 extern const unsigned char pcie_link_speed[];
 extern bool pci_early_dump;
 
-- 
cgit v1.2.3-70-g09d2


From 9972b17712e434f1284bc85d77a2fdbb33db6c51 Mon Sep 17 00:00:00 2001
From: Frank Li <Frank.Li@nxp.com>
Date: Thu, 18 Apr 2024 12:04:27 -0400
Subject: PCI: Add PCIE_MSG_CODE_PME_TURN_OFF message macro
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Add PCIE_MSG_CODE_PME_TURN_OFF macros to enable a PCIe host driver to send
PME_Turn_Off messages.

Link: https://lore.kernel.org/linux-pci/20240418-pme_msg-v8-4-a54265c39742@nxp.com
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/pci/pci.h | 3 +++
 1 file changed, 3 insertions(+)

(limited to 'drivers/pci')

diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 95c95d981241..84b711cad267 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -30,6 +30,9 @@
 #define PCIE_MSG_TYPE_R_LOCAL	4
 #define PCIE_MSG_TYPE_R_GATHER	5
 
+/* Power Management Messages; PCIe r6.0, sec 2.2.8.2 */
+#define PCIE_MSG_CODE_PME_TURN_OFF	0x19
+
 /* INTx Mechanism Messages; PCIe r6.0, sec 2.2.8.1 */
 #define PCIE_MSG_CODE_ASSERT_INTA	0x20
 #define PCIE_MSG_CODE_ASSERT_INTB	0x21
-- 
cgit v1.2.3-70-g09d2


From e1a4ec1a9520bf048a7ee09f7f7a82b1d44750ac Mon Sep 17 00:00:00 2001
From: Frank Li <Frank.Li@nxp.com>
Date: Thu, 18 Apr 2024 12:04:28 -0400
Subject: PCI: dwc: Add generic MSG TLP support for sending PME_Turn_Off when
 system suspend
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Instead of relying on the vendor specific implementations to send the
PME_Turn_Off message, introduce a generic way of sending the message using
the MSG TLP.

This is achieved by reserving a region for MSG TLP of size
'pci->region_align', at the end of the first IORESOURCE_MEM window of the
host bridge. And then sending the PME_Turn_Off message during system
suspend with the help of iATU.

The reason for reserving the MSG TLP region at the end of the
IORESOURCE_MEM is to avoid generating holes in between, because when the
region is allocated using allocate_resource(), memory will be allocated
from the start of the window. Later, if memory gets allocated for an
endpoint of size bigger than 'region_align', there will be a hole between
MSG TLP region and endpoint memory.

This generic implementation is optional for the glue drivers and can be
overridden by a custom 'pme_turn_off' callback.

Link: https://lore.kernel.org/linux-pci/20240418-pme_msg-v8-5-a54265c39742@nxp.com
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/pci/controller/dwc/pcie-designware-host.c | 95 +++++++++++++++++++++--
 drivers/pci/controller/dwc/pcie-designware.h      |  3 +
 2 files changed, 93 insertions(+), 5 deletions(-)

(limited to 'drivers/pci')

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 3a9cb4be22ab..a0822d5371bc 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -398,6 +398,32 @@ static int dw_pcie_msi_host_init(struct dw_pcie_rp *pp)
 	return 0;
 }
 
+static void dw_pcie_host_request_msg_tlp_res(struct dw_pcie_rp *pp)
+{
+	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+	struct resource_entry *win;
+	struct resource *res;
+
+	win = resource_list_first_type(&pp->bridge->windows, IORESOURCE_MEM);
+	if (win) {
+		res = devm_kzalloc(pci->dev, sizeof(*res), GFP_KERNEL);
+		if (!res)
+			return;
+
+		/*
+		 * Allocate MSG TLP region of size 'region_align' at the end of
+		 * the host bridge window.
+		 */
+		res->start = win->res->end - pci->region_align + 1;
+		res->end = win->res->end;
+		res->name = "msg";
+		res->flags = win->res->flags | IORESOURCE_BUSY;
+
+		if (!devm_request_resource(pci->dev, win->res, res))
+			pp->msg_res = res;
+	}
+}
+
 int dw_pcie_host_init(struct dw_pcie_rp *pp)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
@@ -484,6 +510,18 @@ int dw_pcie_host_init(struct dw_pcie_rp *pp)
 
 	dw_pcie_iatu_detect(pci);
 
+	/*
+	 * Allocate the resource for MSG TLP before programming the iATU
+	 * outbound window in dw_pcie_setup_rc(). Since the allocation depends
+	 * on the value of 'region_align', this has to be done after
+	 * dw_pcie_iatu_detect().
+	 *
+	 * Glue drivers need to set 'use_atu_msg' before dw_pcie_host_init() to
+	 * make use of the generic MSG TLP implementation.
+	 */
+	if (pp->use_atu_msg)
+		dw_pcie_host_request_msg_tlp_res(pp);
+
 	ret = dw_pcie_edma_detect(pci);
 	if (ret)
 		goto err_free_msi;
@@ -700,7 +738,13 @@ static int dw_pcie_iatu_setup(struct dw_pcie_rp *pp)
 		atu.type = PCIE_ATU_TYPE_MEM;
 		atu.cpu_addr = entry->res->start;
 		atu.pci_addr = entry->res->start - entry->offset;
-		atu.size = resource_size(entry->res);
+
+		/* Adjust iATU size if MSG TLP region was allocated before */
+		if (pp->msg_res && pp->msg_res->parent == entry->res)
+			atu.size = resource_size(entry->res) -
+					resource_size(pp->msg_res);
+		else
+			atu.size = resource_size(entry->res);
 
 		ret = dw_pcie_prog_outbound_atu(pci, &atu);
 		if (ret) {
@@ -733,6 +777,8 @@ static int dw_pcie_iatu_setup(struct dw_pcie_rp *pp)
 		dev_warn(pci->dev, "Ranges exceed outbound iATU size (%d)\n",
 			 pci->num_ob_windows);
 
+	pp->msg_atu_index = i;
+
 	i = 0;
 	resource_list_for_each_entry(entry, &pp->bridge->dma_ranges) {
 		if (resource_type(entry->res) != IORESOURCE_MEM)
@@ -838,11 +884,47 @@ int dw_pcie_setup_rc(struct dw_pcie_rp *pp)
 }
 EXPORT_SYMBOL_GPL(dw_pcie_setup_rc);
 
+static int dw_pcie_pme_turn_off(struct dw_pcie *pci)
+{
+	struct dw_pcie_ob_atu_cfg atu = { 0 };
+	void __iomem *mem;
+	int ret;
+
+	if (pci->num_ob_windows <= pci->pp.msg_atu_index)
+		return -ENOSPC;
+
+	if (!pci->pp.msg_res)
+		return -ENOSPC;
+
+	atu.code = PCIE_MSG_CODE_PME_TURN_OFF;
+	atu.routing = PCIE_MSG_TYPE_R_BC;
+	atu.type = PCIE_ATU_TYPE_MSG;
+	atu.size = resource_size(pci->pp.msg_res);
+	atu.index = pci->pp.msg_atu_index;
+
+	atu.cpu_addr = pci->pp.msg_res->start;
+
+	ret = dw_pcie_prog_outbound_atu(pci, &atu);
+	if (ret)
+		return ret;
+
+	mem = ioremap(atu.cpu_addr, pci->region_align);
+	if (!mem)
+		return -ENOMEM;
+
+	/* A dummy write is converted to a Msg TLP */
+	writel(0, mem);
+
+	iounmap(mem);
+
+	return 0;
+}
+
 int dw_pcie_suspend_noirq(struct dw_pcie *pci)
 {
 	u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
 	u32 val;
-	int ret;
+	int ret = 0;
 
 	/*
 	 * If L1SS is supported, then do not put the link into L2 as some
@@ -854,10 +936,13 @@ int dw_pcie_suspend_noirq(struct dw_pcie *pci)
 	if (dw_pcie_get_ltssm(pci) <= DW_PCIE_LTSSM_DETECT_ACT)
 		return 0;
 
-	if (!pci->pp.ops->pme_turn_off)
-		return 0;
+	if (pci->pp.ops->pme_turn_off)
+		pci->pp.ops->pme_turn_off(&pci->pp);
+	else
+		ret = dw_pcie_pme_turn_off(pci);
 
-	pci->pp.ops->pme_turn_off(&pci->pp);
+	if (ret)
+		return ret;
 
 	ret = read_poll_timeout(dw_pcie_get_ltssm, val, val == DW_PCIE_LTSSM_L2_IDLE,
 				PCIE_PME_TO_L2_TIMEOUT_US/10,
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 4a3973935979..39ec253df6cf 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -340,6 +340,9 @@ struct dw_pcie_rp {
 	struct pci_host_bridge  *bridge;
 	raw_spinlock_t		lock;
 	DECLARE_BITMAP(msi_irq_in_use, MAX_MSI_IRQS);
+	bool			use_atu_msg;
+	int			msg_atu_index;
+	struct resource		*msg_res;
 };
 
 struct dw_pcie_ep_ops {
-- 
cgit v1.2.3-70-g09d2


From 867ab111b2420ca97e9156ad1e186d2face5c62c Mon Sep 17 00:00:00 2001
From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Date: Tue, 30 Apr 2024 11:43:49 +0530
Subject: PCI: dwc: ep: Add a generic dw_pcie_ep_linkdown() API to handle Link
 Down event
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Per PCIe r6.0, sec 5.2, a Link Down event can happen under any of the
following circumstances:

  1. Fundamental/Hot reset
  2. Link disable transmission by upstream component
  3. Moving from L2/L3 to L0

In those cases, Link Down causes some non-sticky DWC registers to lose the
state (like REBAR, etc.), so drivers need to reinitialize them to function
properly once the link comes back again.

This is not a problem for drivers supporting PERST# IRQ, since they can
reinitialize the registers in the PERST# IRQ callback. But for the drivers
not supporting PERST#, there is no way they can reinitialize the registers
other than relying on Link Down IRQ received when the link goes down. So
add a DWC generic API dw_pcie_ep_linkdown() that reinitializes the
non-sticky registers and also notifies the EPF drivers about link going
down.

This API can also be used by the drivers supporting PERST# to handle the
scenario (2) mentioned above.

NOTE: For the sake of code organization, move the dw_pcie_ep_linkup()
definition just above dw_pcie_ep_linkdown().

Link: https://lore.kernel.org/linux-pci/20240430-pci-epf-rework-v4-8-22832d0d456f@linaro.org
Tested-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
[bhelgaas: update spec citation]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
---
 drivers/pci/controller/dwc/pcie-designware-ep.c | 103 ++++++++++++++++--------
 drivers/pci/controller/dwc/pcie-designware.h    |   5 ++
 2 files changed, 73 insertions(+), 35 deletions(-)

(limited to 'drivers/pci')

diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index 51571da24601..705533e789f3 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -15,18 +15,6 @@
 #include <linux/pci-epc.h>
 #include <linux/pci-epf.h>
 
-/**
- * dw_pcie_ep_linkup - Notify EPF drivers about Link Up event
- * @ep: DWC EP device
- */
-void dw_pcie_ep_linkup(struct dw_pcie_ep *ep)
-{
-	struct pci_epc *epc = ep->epc;
-
-	pci_epc_linkup(epc);
-}
-EXPORT_SYMBOL_GPL(dw_pcie_ep_linkup);
-
 /**
  * dw_pcie_ep_init_notify - Notify EPF drivers about EPC initialization complete
  * @ep: DWC EP device
@@ -685,6 +673,34 @@ static unsigned int dw_pcie_ep_find_ext_capability(struct dw_pcie *pci, int cap)
 	return 0;
 }
 
+static void dw_pcie_ep_init_non_sticky_registers(struct dw_pcie *pci)
+{
+	unsigned int offset;
+	unsigned int nbars;
+	u32 reg, i;
+
+	offset = dw_pcie_ep_find_ext_capability(pci, PCI_EXT_CAP_ID_REBAR);
+
+	dw_pcie_dbi_ro_wr_en(pci);
+
+	if (offset) {
+		reg = dw_pcie_readl_dbi(pci, offset + PCI_REBAR_CTRL);
+		nbars = (reg & PCI_REBAR_CTRL_NBAR_MASK) >>
+			PCI_REBAR_CTRL_NBAR_SHIFT;
+
+		/*
+		 * PCIe r6.0, sec 7.8.6.2 require us to support at least one
+		 * size in the range from 1 MB to 512 GB. Advertise support
+		 * for 1 MB BAR size only.
+		 */
+		for (i = 0; i < nbars; i++, offset += PCI_REBAR_CTRL)
+			dw_pcie_writel_dbi(pci, offset + PCI_REBAR_CAP, 0x0);
+	}
+
+	dw_pcie_setup(pci);
+	dw_pcie_dbi_ro_wr_dis(pci);
+}
+
 /**
  * dw_pcie_ep_init_registers - Initialize DWC EP specific registers
  * @ep: DWC EP device
@@ -699,13 +715,11 @@ int dw_pcie_ep_init_registers(struct dw_pcie_ep *ep)
 	struct dw_pcie_ep_func *ep_func;
 	struct device *dev = pci->dev;
 	struct pci_epc *epc = ep->epc;
-	unsigned int offset, ptm_cap_base;
-	unsigned int nbars;
+	u32 ptm_cap_base, reg;
 	u8 hdr_type;
 	u8 func_no;
-	int i, ret;
 	void *addr;
-	u32 reg;
+	int ret;
 
 	hdr_type = dw_pcie_readb_dbi(pci, PCI_HEADER_TYPE) &
 		   PCI_HEADER_TYPE_MASK;
@@ -768,25 +782,8 @@ int dw_pcie_ep_init_registers(struct dw_pcie_ep *ep)
 	if (ep->ops->init)
 		ep->ops->init(ep);
 
-	offset = dw_pcie_ep_find_ext_capability(pci, PCI_EXT_CAP_ID_REBAR);
 	ptm_cap_base = dw_pcie_ep_find_ext_capability(pci, PCI_EXT_CAP_ID_PTM);
 
-	dw_pcie_dbi_ro_wr_en(pci);
-
-	if (offset) {
-		reg = dw_pcie_readl_dbi(pci, offset + PCI_REBAR_CTRL);
-		nbars = (reg & PCI_REBAR_CTRL_NBAR_MASK) >>
-			PCI_REBAR_CTRL_NBAR_SHIFT;
-
-		/*
-		 * PCIe r6.0, sec 7.8.6.2 require us to support at least one
-		 * size in the range from 1 MB to 512 GB. Advertise support
-		 * for 1 MB BAR size only.
-		 */
-		for (i = 0; i < nbars; i++, offset += PCI_REBAR_CTRL)
-			dw_pcie_writel_dbi(pci, offset + PCI_REBAR_CAP, BIT(4));
-	}
-
 	/*
 	 * PTM responder capability can be disabled only after disabling
 	 * PTM root capability.
@@ -803,8 +800,7 @@ int dw_pcie_ep_init_registers(struct dw_pcie_ep *ep)
 		dw_pcie_dbi_ro_wr_dis(pci);
 	}
 
-	dw_pcie_setup(pci);
-	dw_pcie_dbi_ro_wr_dis(pci);
+	dw_pcie_ep_init_non_sticky_registers(pci);
 
 	return 0;
 
@@ -815,6 +811,43 @@ err_remove_edma:
 }
 EXPORT_SYMBOL_GPL(dw_pcie_ep_init_registers);
 
+/**
+ * dw_pcie_ep_linkup - Notify EPF drivers about Link Up event
+ * @ep: DWC EP device
+ */
+void dw_pcie_ep_linkup(struct dw_pcie_ep *ep)
+{
+	struct pci_epc *epc = ep->epc;
+
+	pci_epc_linkup(epc);
+}
+EXPORT_SYMBOL_GPL(dw_pcie_ep_linkup);
+
+/**
+ * dw_pcie_ep_linkdown - Notify EPF drivers about Link Down event
+ * @ep: DWC EP device
+ *
+ * Non-sticky registers are also initialized before sending the notification to
+ * the EPF drivers. This is needed since the registers need to be initialized
+ * before the link comes back again.
+ */
+void dw_pcie_ep_linkdown(struct dw_pcie_ep *ep)
+{
+	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+	struct pci_epc *epc = ep->epc;
+
+	/*
+	 * Initialize the non-sticky DWC registers as they would've reset post
+	 * Link Down. This is specifically needed for drivers not supporting
+	 * PERST# as they have no way to reinitialize the registers before the
+	 * link comes back again.
+	 */
+	dw_pcie_ep_init_non_sticky_registers(pci);
+
+	pci_epc_linkdown(epc);
+}
+EXPORT_SYMBOL_GPL(dw_pcie_ep_linkdown);
+
 /**
  * dw_pcie_ep_init - Initialize the endpoint device
  * @ep: DWC EP device
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 39ec253df6cf..5822eb09ead7 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -681,6 +681,7 @@ static inline void __iomem *dw_pcie_own_conf_map_bus(struct pci_bus *bus,
 
 #ifdef CONFIG_PCIE_DW_EP
 void dw_pcie_ep_linkup(struct dw_pcie_ep *ep);
+void dw_pcie_ep_linkdown(struct dw_pcie_ep *ep);
 int dw_pcie_ep_init(struct dw_pcie_ep *ep);
 int dw_pcie_ep_init_registers(struct dw_pcie_ep *ep);
 void dw_pcie_ep_init_notify(struct dw_pcie_ep *ep);
@@ -701,6 +702,10 @@ static inline void dw_pcie_ep_linkup(struct dw_pcie_ep *ep)
 {
 }
 
+static inline void dw_pcie_ep_linkdown(struct dw_pcie_ep *ep)
+{
+}
+
 static inline int dw_pcie_ep_init(struct dw_pcie_ep *ep)
 {
 	return 0;
-- 
cgit v1.2.3-70-g09d2


From 245b9ebf7b8e2a79c207337ee78061ff8e0c774b Mon Sep 17 00:00:00 2001
From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Date: Thu, 6 Jun 2024 12:56:34 +0530
Subject: PCI: dwc: ep: Remove dw_pcie_ep_init_notify() wrapper
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Currently dw_pcie_ep_init_notify() wrapper just calls pci_epc_init_notify()
directly, so this wrapper provides no benefit to the glue drivers.

Remove it and call pci_epc_init_notify() directly from glue drivers.

Suggested-by: Bjorn Helgaas <helgaas@kernel.org>
Link: https://lore.kernel.org/linux-pci/20240606-pci-deinit-v1-1-4395534520dc@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Siddharth Vadapalli <s-vadapalli@ti.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
---
 drivers/pci/controller/dwc/pci-dra7xx.c           |  2 +-
 drivers/pci/controller/dwc/pci-imx6.c             |  2 +-
 drivers/pci/controller/dwc/pci-keystone.c         |  2 +-
 drivers/pci/controller/dwc/pci-layerscape-ep.c    |  2 +-
 drivers/pci/controller/dwc/pcie-artpec6.c         |  2 +-
 drivers/pci/controller/dwc/pcie-designware-ep.c   | 12 ------------
 drivers/pci/controller/dwc/pcie-designware-plat.c |  2 +-
 drivers/pci/controller/dwc/pcie-designware.h      |  5 -----
 drivers/pci/controller/dwc/pcie-keembay.c         |  2 +-
 drivers/pci/controller/dwc/pcie-qcom-ep.c         |  2 +-
 drivers/pci/controller/dwc/pcie-rcar-gen4.c       |  2 +-
 drivers/pci/controller/dwc/pcie-tegra194.c        |  2 +-
 drivers/pci/controller/dwc/pcie-uniphier-ep.c     |  2 +-
 13 files changed, 11 insertions(+), 28 deletions(-)

(limited to 'drivers/pci')

diff --git a/drivers/pci/controller/dwc/pci-dra7xx.c b/drivers/pci/controller/dwc/pci-dra7xx.c
index d2d17d37d3e0..e491d0ff3962 100644
--- a/drivers/pci/controller/dwc/pci-dra7xx.c
+++ b/drivers/pci/controller/dwc/pci-dra7xx.c
@@ -474,7 +474,7 @@ static int dra7xx_add_pcie_ep(struct dra7xx_pcie *dra7xx,
 		return ret;
 	}
 
-	dw_pcie_ep_init_notify(ep);
+	pci_epc_init_notify(ep->epc);
 
 	return 0;
 }
diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 917c69edee1d..a876b8e6e741 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -1131,7 +1131,7 @@ static int imx6_add_pcie_ep(struct imx6_pcie *imx6_pcie,
 		return ret;
 	}
 
-	dw_pcie_ep_init_notify(ep);
+	pci_epc_init_notify(ep->epc);
 
 	/* Start LTSSM. */
 	imx6_pcie_ltssm_enable(dev);
diff --git a/drivers/pci/controller/dwc/pci-keystone.c b/drivers/pci/controller/dwc/pci-keystone.c
index d3a7d14ee685..ca1054f5c79a 100644
--- a/drivers/pci/controller/dwc/pci-keystone.c
+++ b/drivers/pci/controller/dwc/pci-keystone.c
@@ -1293,7 +1293,7 @@ static int ks_pcie_probe(struct platform_device *pdev)
 			goto err_ep_init;
 		}
 
-		dw_pcie_ep_init_notify(&pci->ep);
+		pci_epc_init_notify(pci->ep.epc);
 
 		break;
 	default:
diff --git a/drivers/pci/controller/dwc/pci-layerscape-ep.c b/drivers/pci/controller/dwc/pci-layerscape-ep.c
index 7dde6d5fa4d8..35bb481564c7 100644
--- a/drivers/pci/controller/dwc/pci-layerscape-ep.c
+++ b/drivers/pci/controller/dwc/pci-layerscape-ep.c
@@ -286,7 +286,7 @@ static int __init ls_pcie_ep_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	dw_pcie_ep_init_notify(&pci->ep);
+	pci_epc_init_notify(pci->ep.epc);
 
 	return ls_pcie_ep_interrupt_init(pcie, pdev);
 }
diff --git a/drivers/pci/controller/dwc/pcie-artpec6.c b/drivers/pci/controller/dwc/pcie-artpec6.c
index a4630b92489b..dc8dd7f27b78 100644
--- a/drivers/pci/controller/dwc/pcie-artpec6.c
+++ b/drivers/pci/controller/dwc/pcie-artpec6.c
@@ -452,7 +452,7 @@ static int artpec6_pcie_probe(struct platform_device *pdev)
 			return ret;
 		}
 
-		dw_pcie_ep_init_notify(&pci->ep);
+		pci_epc_init_notify(pci->ep.epc);
 
 		break;
 	default:
diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index 705533e789f3..bdbdd099405a 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -15,18 +15,6 @@
 #include <linux/pci-epc.h>
 #include <linux/pci-epf.h>
 
-/**
- * dw_pcie_ep_init_notify - Notify EPF drivers about EPC initialization complete
- * @ep: DWC EP device
- */
-void dw_pcie_ep_init_notify(struct dw_pcie_ep *ep)
-{
-	struct pci_epc *epc = ep->epc;
-
-	pci_epc_init_notify(epc);
-}
-EXPORT_SYMBOL_GPL(dw_pcie_ep_init_notify);
-
 /**
  * dw_pcie_ep_get_func_from_ep - Get the struct dw_pcie_ep_func corresponding to
  *				 the endpoint function
diff --git a/drivers/pci/controller/dwc/pcie-designware-plat.c b/drivers/pci/controller/dwc/pcie-designware-plat.c
index 8490c5d6ff9f..771b9d9be077 100644
--- a/drivers/pci/controller/dwc/pcie-designware-plat.c
+++ b/drivers/pci/controller/dwc/pcie-designware-plat.c
@@ -154,7 +154,7 @@ static int dw_plat_pcie_probe(struct platform_device *pdev)
 			dw_pcie_ep_deinit(&pci->ep);
 		}
 
-		dw_pcie_ep_init_notify(&pci->ep);
+		pci_epc_init_notify(pci->ep.epc);
 
 		break;
 	default:
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 5822eb09ead7..069c72f318a7 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -684,7 +684,6 @@ void dw_pcie_ep_linkup(struct dw_pcie_ep *ep);
 void dw_pcie_ep_linkdown(struct dw_pcie_ep *ep);
 int dw_pcie_ep_init(struct dw_pcie_ep *ep);
 int dw_pcie_ep_init_registers(struct dw_pcie_ep *ep);
-void dw_pcie_ep_init_notify(struct dw_pcie_ep *ep);
 void dw_pcie_ep_deinit(struct dw_pcie_ep *ep);
 void dw_pcie_ep_cleanup(struct dw_pcie_ep *ep);
 int dw_pcie_ep_raise_intx_irq(struct dw_pcie_ep *ep, u8 func_no);
@@ -716,10 +715,6 @@ static inline int dw_pcie_ep_init_registers(struct dw_pcie_ep *ep)
 	return 0;
 }
 
-static inline void dw_pcie_ep_init_notify(struct dw_pcie_ep *ep)
-{
-}
-
 static inline void dw_pcie_ep_deinit(struct dw_pcie_ep *ep)
 {
 }
diff --git a/drivers/pci/controller/dwc/pcie-keembay.c b/drivers/pci/controller/dwc/pcie-keembay.c
index 98bbc83182b4..278205db60a2 100644
--- a/drivers/pci/controller/dwc/pcie-keembay.c
+++ b/drivers/pci/controller/dwc/pcie-keembay.c
@@ -442,7 +442,7 @@ static int keembay_pcie_probe(struct platform_device *pdev)
 			return ret;
 		}
 
-		dw_pcie_ep_init_notify(&pci->ep);
+		pci_epc_init_notify(pci->ep.epc);
 
 		break;
 	default:
diff --git a/drivers/pci/controller/dwc/pcie-qcom-ep.c b/drivers/pci/controller/dwc/pcie-qcom-ep.c
index b6a5010cc1a7..2324e56c9bfc 100644
--- a/drivers/pci/controller/dwc/pcie-qcom-ep.c
+++ b/drivers/pci/controller/dwc/pcie-qcom-ep.c
@@ -482,7 +482,7 @@ static int qcom_pcie_perst_deassert(struct dw_pcie *pci)
 	val &= ~PARF_MSTR_AXI_CLK_EN;
 	writel_relaxed(val, pcie_ep->parf + PARF_MHI_CLOCK_RESET_CTRL);
 
-	dw_pcie_ep_init_notify(&pcie_ep->pci.ep);
+	pci_epc_init_notify(pcie_ep->pci.ep.epc);
 
 	/* Enable LTSSM */
 	val = readl_relaxed(pcie_ep->parf + PARF_LTSSM);
diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
index cfeccc2f9ee1..237a6a8818de 100644
--- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
+++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
@@ -437,7 +437,7 @@ static int rcar_gen4_add_dw_pcie_ep(struct rcar_gen4_pcie *rcar)
 		rcar_gen4_pcie_ep_deinit(rcar);
 	}
 
-	dw_pcie_ep_init_notify(ep);
+	pci_epc_init_notify(ep->epc);
 
 	return ret;
 }
diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index 4b28f8beedfe..4ca7404246a3 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -1904,7 +1904,7 @@ static void pex_ep_event_pex_rst_deassert(struct tegra_pcie_dw *pcie)
 		goto fail_init_complete;
 	}
 
-	dw_pcie_ep_init_notify(ep);
+	pci_epc_init_notify(ep->epc);
 
 	/* Program the private control to allow sending LTR upstream */
 	if (pcie->of_data->has_ltr_req_fix) {
diff --git a/drivers/pci/controller/dwc/pcie-uniphier-ep.c b/drivers/pci/controller/dwc/pcie-uniphier-ep.c
index a2b844268e28..d6e73811216e 100644
--- a/drivers/pci/controller/dwc/pcie-uniphier-ep.c
+++ b/drivers/pci/controller/dwc/pcie-uniphier-ep.c
@@ -410,7 +410,7 @@ static int uniphier_pcie_ep_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	dw_pcie_ep_init_notify(&priv->pci.ep);
+	pci_epc_init_notify(priv->pci.ep.epc);
 
 	return 0;
 }
-- 
cgit v1.2.3-70-g09d2


From 574621166c8f60c2d0534cdb3a3cf6e1a37a19d0 Mon Sep 17 00:00:00 2001
From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Date: Tue, 30 Apr 2024 11:43:50 +0530
Subject: PCI: qcom-ep: Use the generic dw_pcie_ep_linkdown() API to handle
 Link Down event
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Now that the generic dw_pcie_ep_linkdown() API is available, use it. This
also handles the reinitialization of DWC non-sticky registers in addition
to sending the notification to EPF drivers.

Link: https://lore.kernel.org/linux-pci/20240430-pci-epf-rework-v4-9-22832d0d456f@linaro.org
Tested-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
---
 drivers/pci/controller/dwc/pcie-qcom-ep.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'drivers/pci')

diff --git a/drivers/pci/controller/dwc/pcie-qcom-ep.c b/drivers/pci/controller/dwc/pcie-qcom-ep.c
index 2324e56c9bfc..02a2a871a91f 100644
--- a/drivers/pci/controller/dwc/pcie-qcom-ep.c
+++ b/drivers/pci/controller/dwc/pcie-qcom-ep.c
@@ -641,7 +641,7 @@ static irqreturn_t qcom_pcie_ep_global_irq_thread(int irq, void *data)
 	if (FIELD_GET(PARF_INT_ALL_LINK_DOWN, status)) {
 		dev_dbg(dev, "Received Linkdown event\n");
 		pcie_ep->link_status = QCOM_PCIE_EP_LINK_DOWN;
-		pci_epc_linkdown(pci->ep.epc);
+		dw_pcie_ep_linkdown(&pci->ep);
 	} else if (FIELD_GET(PARF_INT_ALL_BME, status)) {
 		dev_dbg(dev, "Received Bus Master Enable event\n");
 		pcie_ep->link_status = QCOM_PCIE_EP_LINK_ENABLED;
-- 
cgit v1.2.3-70-g09d2


From b8747e10fde9573834b9f320593422e37af1af97 Mon Sep 17 00:00:00 2001
From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Date: Thu, 6 Jun 2024 12:56:38 +0530
Subject: PCI: layerscape-ep: Use the generic dw_pcie_ep_linkdown() API to
 handle Link Down event
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Now that dw_pcie_ep_linkdown() is available, use it. This also handles the
reinitialization of DWC non-sticky registers in addition to sending the
notification to EPF drivers.

Closes: https://lore.kernel.org/linux-pci/20240528195539.GA458945@bhelgaas
Link: https://lore.kernel.org/linux-pci/20240606-pci-deinit-v1-5-4395534520dc@linaro.org
Reported-by: Bjorn Helgaas <helgaas@kernel.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
---
 drivers/pci/controller/dwc/pci-layerscape-ep.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'drivers/pci')

diff --git a/drivers/pci/controller/dwc/pci-layerscape-ep.c b/drivers/pci/controller/dwc/pci-layerscape-ep.c
index 35bb481564c7..a4a800699f89 100644
--- a/drivers/pci/controller/dwc/pci-layerscape-ep.c
+++ b/drivers/pci/controller/dwc/pci-layerscape-ep.c
@@ -104,7 +104,7 @@ static irqreturn_t ls_pcie_ep_event_handler(int irq, void *dev_id)
 		dev_dbg(pci->dev, "Link up\n");
 	} else if (val & PEX_PF0_PME_MES_DR_LDD) {
 		dev_dbg(pci->dev, "Link down\n");
-		pci_epc_linkdown(pci->ep.epc);
+		dw_pcie_ep_linkdown(&pci->ep);
 	} else if (val & PEX_PF0_PME_MES_DR_HRD) {
 		dev_dbg(pci->dev, "Hot reset\n");
 	}
-- 
cgit v1.2.3-70-g09d2


From 9b10e877fc847f161aa4e6c918799002ad6dad23 Mon Sep 17 00:00:00 2001
From: Niklas Cassel <cassel@kernel.org>
Date: Tue, 28 May 2024 15:48:40 +0200
Subject: PCI: dwc: ep: Enforce DWC specific 64-bit BAR limitation
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

From the DWC EP databook 5.96a, section "3.5.7.1.4 General Rules for BAR
Setup (Fixed Mask or Programmable Mask Schemes Only)":

"Any pair (for example BARs 0 and 1) can be configured as one 64-bit BAR,
two 32-bit BARs, or one 32-bit BAR."

"BAR pairs cannot overlap to form a 64-bit BAR. For example, you cannot
combine BARs 1 and 2 to form a 64-bit BAR."

While this limitation does exist in some other PCI endpoint controllers,
e.g. cdns_pcie_ep_set_bar(), the limitation does not appear to be defined
in the PCIe specification itself, thus add an explicit check for this in
dw_pcie_ep_set_bar() (rather than pci_epc_set_bar()).

Link: https://lore.kernel.org/linux-pci/20240528134839.8817-2-cassel@kernel.org
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/pci/controller/dwc/pcie-designware-ep.c | 7 +++++++
 1 file changed, 7 insertions(+)

(limited to 'drivers/pci')

diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index bdbdd099405a..43ba5c6738df 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -215,6 +215,13 @@ static int dw_pcie_ep_set_bar(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
 	int ret, type;
 	u32 reg;
 
+	/*
+	 * DWC does not allow BAR pairs to overlap, e.g. you cannot combine BARs
+	 * 1 and 2 to form a 64-bit BAR.
+	 */
+	if ((flags & PCI_BASE_ADDRESS_MEM_TYPE_64) && (bar & 1))
+		return -EINVAL;
+
 	reg = PCI_BASE_ADDRESS_0 + (4 * bar);
 
 	if (!(flags & PCI_BASE_ADDRESS_SPACE))
-- 
cgit v1.2.3-70-g09d2