Merge tag 'pci-v6.8-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci

Pull pci updates from Bjorn Helgaas:
 "Enumeration:

   - Reserve ECAM so we don't assign it to PCI BARs; this works around
     bugs where BIOS included ECAM in a PNP0A03 host bridge window,
     didn't reserve it via a PNP0C02 motherboard device, and didn't
     allocate space for SR-IOV VF BARs (Bjorn Helgaas)

   - Add MMCONFIG/ECAM debug logging (Bjorn Helgaas)

   - Rename 'MMCONFIG' to 'ECAM' to match spec usage (Bjorn Helgaas)

   - Log device type (Root Port, Switch Port, etc) during enumeration
     (Bjorn Helgaas)

   - Log bridges before downstream devices so the dmesg order is more
     logical (Bjorn Helgaas)

   - Log resource names (BAR 0, VF BAR 0, bridge window, etc)
     consistently instead of a mix of names and "reg 0x10" (Puranjay
     Mohan, Bjorn Helgaas)

   - Fix 64GT/s effective data rate calculation to use 1b/1b encoding
     rather than the 8b/10b or 128b/130b used by lower rates (Ilpo
     Järvinen)

   - Use PCI_HEADER_TYPE_* instead of literals in x86, powerpc, SCSI
     lpfc (Ilpo Järvinen)

   - Clean up open-coded PCIBIOS return code mangling (Ilpo Järvinen)

  Resource management:

   - Restructure pci_dev_for_each_resource() to avoid computing the
     address of an out-of-bounds array element (the bounds check was
     performed later so the element was never actually *read*, but it's
     nicer to avoid even computing an out-of-bounds address) (Andy
     Shevchenko)

  Driver binding:

   - Convert pci-host-common.c platform .remove() callback to
     .remove_new() returning 'void' since it's not useful to return
     error codes here (Uwe Kleine-König)

   - Convert exynos, keystone, kirin from .remove() to .remove_new(),
     which returns void instead of int (Uwe Kleine-König)

   - Drop unused struct pci_driver.node member (Mathias Krause)

  Virtualization:

   - Add ACS quirk for more Zhaoxin Root Ports (LeoLiuoc)

  Error handling:

   - Log AER errors as "Correctable" (not "Corrected") or
     "Uncorrectable" to match spec terminology (Bjorn Helgaas)

   - Decode Requester ID when no error info found instead of printing
     the raw hex value (Bjorn Helgaas)

  Endpoint framework:

   - Use a unique test pattern for each BAR in the pci_endpoint_test to
     make it easier to debug address translation issues (Niklas Cassel)

  Broadcom STB PCIe controller driver:

   - Add DT property "brcm,clkreq-mode" and driver support for different
     CLKREQ# modes to make ASPM L1.x states possible (Jim Quinlan)

  Freescale Layerscape PCIe controller driver:

   - Add suspend/resume support for Layerscape LS1043a and LS1021a,
     including software-managed PME_Turn_Off and transitions between L0,
     L2/L3_Ready Link states (Frank Li)

  MediaTek PCIe controller driver:

   - Clear MSI interrupt status before handler to avoid missing MSIs
     that occur after the handler (qizhong cheng)

  MediaTek PCIe Gen3 controller driver:

   - Update mediatek-gen3 translation window setup to handle MMIO space
     that is not a power of two in size (Jianjun Wang)

  Qualcomm PCIe controller driver:

   - Increase qcom iommu-map maxItems to accommodate SDX55 (five
     entries) and SDM845 (sixteen entries) (Krzysztof Kozlowski)

   - Describe qcom,pcie-sc8180x clocks and resets accurately (Krzysztof
     Kozlowski)

   - Describe qcom,pcie-sm8150 clocks and resets accurately (Krzysztof
     Kozlowski)

   - Correct the qcom "reset-name" property, previously incorrectly
     called "reset-names" (Krzysztof Kozlowski)

   - Document qcom,pcie-sm8650, based on qcom,pcie-sm8550 (Neil
     Armstrong)

  Renesas R-Car PCIe controller driver:

   - Replace of_device.h with explicit of.h include to untangle header
     usage (Rob Herring)

   - Add DT and driver support for optional miniPCIe 1.5v and 3.3v
     regulators on KingFisher (Wolfram Sang)

  SiFive FU740 PCIe controller driver:

   - Convert fu740 CONFIG_PCIE_FU740 dependency from SOC_SIFIVE to
     ARCH_SIFIVE (Conor Dooley)

  Synopsys DesignWare PCIe controller driver:

   - Align iATU mapping for endpoint MSI-X (Niklas Cassel)

   - Drop "host_" prefix from struct dw_pcie_host_ops members (Yoshihiro
     Shimoda)

   - Drop "ep_" prefix from struct dw_pcie_ep_ops members (Yoshihiro
     Shimoda)

   - Rename struct dw_pcie_ep_ops.func_conf_select() to
     .get_dbi_offset() to be more descriptive (Yoshihiro Shimoda)

   - Add Endpoint DBI accessors to encapsulate offset lookups (Yoshihiro
     Shimoda)

  TI J721E PCIe driver:

   - Add j721e DT and driver support for 'num-lanes' for devices that
     support x1, x2, or x4 Links (Matt Ranostay)

   - Add j721e DT compatible strings and driver support for j784s4 (Matt
     Ranostay)

   - Make TI J721E Kconfig depend on ARCH_K3 since the hardware is
     specific to those TI SoC parts (Peter Robinson)

  TI Keystone PCIe controller driver:

   - Hold power management references to all PHYs while enabling them to
     avoid a race when one provides clocks to others (Siddharth
     Vadapalli)

  Xilinx XDMA PCIe controller driver:

   - Remove redundant dev_err(), since platform_get_irq() and
     platform_get_irq_byname() already log errors (Yang Li)

   - Fix uninitialized symbols in xilinx_pl_dma_pcie_setup_irq()
     (Krzysztof Wilczyński)

   - Fix xilinx_pl_dma_pcie_init_irq_domain() error return when
     irq_domain_add_linear() fails (Harshit Mogalapalli)

  MicroSemi Switchtec management driver:

   - Do dma_mrpc cleanup during switchtec_pci_remove() to match its devm
     ioremapping in switchtec_pci_probe(). Previously the cleanup was
     done in stdev_release(), which used stale pointers if stdev->cdev
     happened to be open when the PCI device was removed (Daniel
     Stodden)

  Miscellaneous:

   - Convert interrupt terminology from "legacy" to "INTx" to be more
     specific and match spec terminology (Damien Le Moal)

   - In dw-xdata-pcie, pci_endpoint_test, and vmd, replace usage of
     deprecated ida_simple_*() API with ida_alloc() and ida_free()
     (Christophe JAILLET)"

* tag 'pci-v6.8-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (97 commits)
  PCI: Fix kernel-doc issues
  PCI: brcmstb: Configure HW CLKREQ# mode appropriate for downstream device
  dt-bindings: PCI: brcmstb: Add property "brcm,clkreq-mode"
  PCI: mediatek-gen3: Fix translation window size calculation
  PCI: mediatek: Clear interrupt status before dispatching handler
  PCI: keystone: Fix race condition when initializing PHYs
  PCI: xilinx-xdma: Fix error code in xilinx_pl_dma_pcie_init_irq_domain()
  PCI: xilinx-xdma: Fix uninitialized symbols in xilinx_pl_dma_pcie_setup_irq()
  PCI: rcar-gen4: Fix -Wvoid-pointer-to-enum-cast error
  PCI: iproc: Fix -Wvoid-pointer-to-enum-cast warning
  PCI: dwc: Add dw_pcie_ep_{read,write}_dbi[2] helpers
  PCI: dwc: Rename .func_conf_select to .get_dbi_offset in struct dw_pcie_ep_ops
  PCI: dwc: Rename .ep_init to .init in struct dw_pcie_ep_ops
  PCI: dwc: Drop host prefix from struct dw_pcie_host_ops members
  misc: pci_endpoint_test: Use a unique test pattern for each BAR
  PCI: j721e: Make TI J721E depend on ARCH_K3
  PCI: j721e: Add TI J784S4 PCIe configuration
  PCI/AER: Use explicit register sizes for struct members
  PCI/AER: Decode Requester ID when no error info found
  PCI/AER: Use 'Correctable' and 'Uncorrectable' spec terms for errors
  ...

1 files changed, 86 insertions, 10 deletions

diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c
index f9dd6622fe10..5b0730c3891b 100644
--- a/drivers/pci/controller/pcie-brcmstb.c
+++ b/drivers/pci/controller/pcie-brcmstb.c
@@ -48,6 +48,9 @@
 #define PCIE_RC_CFG_PRIV1_LINK_CAPABILITY			0x04dc
 #define  PCIE_RC_CFG_PRIV1_LINK_CAPABILITY_ASPM_SUPPORT_MASK	0xc00
 
+#define PCIE_RC_CFG_PRIV1_ROOT_CAP			0x4f8
+#define  PCIE_RC_CFG_PRIV1_ROOT_CAP_L1SS_MODE_MASK	0xf8
+
 #define PCIE_RC_DL_MDIO_ADDR				0x1100
 #define PCIE_RC_DL_MDIO_WR_DATA				0x1104
 #define PCIE_RC_DL_MDIO_RD_DATA				0x1108
@@ -121,9 +124,12 @@
 
 #define PCIE_MISC_HARD_PCIE_HARD_DEBUG					0x4204
 #define  PCIE_MISC_HARD_PCIE_HARD_DEBUG_CLKREQ_DEBUG_ENABLE_MASK	0x2
+#define  PCIE_MISC_HARD_PCIE_HARD_DEBUG_L1SS_ENABLE_MASK		0x200000
 #define  PCIE_MISC_HARD_PCIE_HARD_DEBUG_SERDES_IDDQ_MASK		0x08000000
 #define  PCIE_BMIPS_MISC_HARD_PCIE_HARD_DEBUG_SERDES_IDDQ_MASK		0x00800000
-
+#define  PCIE_CLKREQ_MASK \
+	  (PCIE_MISC_HARD_PCIE_HARD_DEBUG_CLKREQ_DEBUG_ENABLE_MASK | \
+	   PCIE_MISC_HARD_PCIE_HARD_DEBUG_L1SS_ENABLE_MASK)
 
 #define PCIE_INTR2_CPU_BASE		0x4300
 #define PCIE_MSI_INTR2_BASE		0x4500
@@ -1028,13 +1034,89 @@ static int brcm_pcie_setup(struct brcm_pcie *pcie)
 	return 0;
 }
 
+/*
+ * This extends the timeout period for an access to an internal bus.  This
+ * access timeout may occur during L1SS sleep periods, even without the
+ * presence of a PCIe access.
+ */
+static void brcm_extend_rbus_timeout(struct brcm_pcie *pcie)
+{
+	/* TIMEOUT register is two registers before RGR1_SW_INIT_1 */
+	const unsigned int REG_OFFSET = PCIE_RGR1_SW_INIT_1(pcie) - 8;
+	u32 timeout_us = 4000000; /* 4 seconds, our setting for L1SS */
+
+	/* Each unit in timeout register is 1/216,000,000 seconds */
+	writel(216 * timeout_us, pcie->base + REG_OFFSET);
+}
+
+static void brcm_config_clkreq(struct brcm_pcie *pcie)
+{
+	static const char err_msg[] = "invalid 'brcm,clkreq-mode' DT string\n";
+	const char *mode = "default";
+	u32 clkreq_cntl;
+	int ret, tmp;
+
+	ret = of_property_read_string(pcie->np, "brcm,clkreq-mode", &mode);
+	if (ret && ret != -EINVAL) {
+		dev_err(pcie->dev, err_msg);
+		mode = "safe";
+	}
+
+	/* Start out assuming safe mode (both mode bits cleared) */
+	clkreq_cntl = readl(pcie->base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
+	clkreq_cntl &= ~PCIE_CLKREQ_MASK;
+
+	if (strcmp(mode, "no-l1ss") == 0) {
+		/*
+		 * "no-l1ss" -- Provides Clock Power Management, L0s, and
+		 * L1, but cannot provide L1 substate (L1SS) power
+		 * savings. If the downstream device connected to the RC is
+		 * L1SS capable AND the OS enables L1SS, all PCIe traffic
+		 * may abruptly halt, potentially hanging the system.
+		 */
+		clkreq_cntl |= PCIE_MISC_HARD_PCIE_HARD_DEBUG_CLKREQ_DEBUG_ENABLE_MASK;
+		/*
+		 * We want to un-advertise L1 substates because if the OS
+		 * tries to configure the controller into using L1 substate
+		 * power savings it may fail or hang when the RC HW is in
+		 * "no-l1ss" mode.
+		 */
+		tmp = readl(pcie->base + PCIE_RC_CFG_PRIV1_ROOT_CAP);
+		u32p_replace_bits(&tmp, 2, PCIE_RC_CFG_PRIV1_ROOT_CAP_L1SS_MODE_MASK);
+		writel(tmp, pcie->base + PCIE_RC_CFG_PRIV1_ROOT_CAP);
+
+	} else if (strcmp(mode, "default") == 0) {
+		/*
+		 * "default" -- Provides L0s, L1, and L1SS, but not
+		 * compliant to provide Clock Power Management;
+		 * specifically, may not be able to meet the Tclron max
+		 * timing of 400ns as specified in "Dynamic Clock Control",
+		 * section 3.2.5.2.2 of the PCIe spec.  This situation is
+		 * atypical and should happen only with older devices.
+		 */
+		clkreq_cntl |= PCIE_MISC_HARD_PCIE_HARD_DEBUG_L1SS_ENABLE_MASK;
+		brcm_extend_rbus_timeout(pcie);
+
+	} else {
+		/*
+		 * "safe" -- No power savings; refclk is driven by RC
+		 * unconditionally.
+		 */
+		if (strcmp(mode, "safe") != 0)
+			dev_err(pcie->dev, err_msg);
+		mode = "safe";
+	}
+	writel(clkreq_cntl, pcie->base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
+
+	dev_info(pcie->dev, "clkreq-mode set to %s\n", mode);
+}
+
 static int brcm_pcie_start_link(struct brcm_pcie *pcie)
 {
 	struct device *dev = pcie->dev;
 	void __iomem *base = pcie->base;
 	u16 nlw, cls, lnksta;
 	bool ssc_good = false;
-	u32 tmp;
 	int ret, i;
 
 	/* Unassert the fundamental reset */
@@ -1059,6 +1141,8 @@ static int brcm_pcie_start_link(struct brcm_pcie *pcie)
 		return -ENODEV;
 	}
 
+	brcm_config_clkreq(pcie);
+
 	if (pcie->gen)
 		brcm_pcie_set_gen(pcie, pcie->gen);
 
@@ -1077,14 +1161,6 @@ static int brcm_pcie_start_link(struct brcm_pcie *pcie)
 		 pci_speed_string(pcie_link_speed[cls]), nlw,
 		 ssc_good ? "(SSC)" : "(!SSC)");
 
-	/*
-	 * Refclk from RC should be gated with CLKREQ# input when ASPM L0s,L1
-	 * is enabled => setting the CLKREQ_DEBUG_ENABLE field to 1.
-	 */
-	tmp = readl(base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
-	tmp |= PCIE_MISC_HARD_PCIE_HARD_DEBUG_CLKREQ_DEBUG_ENABLE_MASK;
-	writel(tmp, base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
-
 	return 0;
 }