From 7ccc4f4e2e50e4a29f9ee8f5c9e187f8491bb6e7 Mon Sep 17 00:00:00 2001 From: Mario Limonciello Date: Fri, 10 Mar 2023 15:19:47 -0600 Subject: crypto: ccp - Add support for an interface for platform features Some platforms with a PSP support an interface for features that interact directly with the PSP instead of through a SEV or TEE environment. Initialize this interface so that other drivers can consume it. These drivers may either be subdrivers for the ccp module or external modules. For external modules, export a symbol for them to utilize. Acked-by: Tom Lendacky Signed-off-by: Mario Limonciello Signed-off-by: Herbert Xu --- include/linux/psp-platform-access.h | 49 +++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 include/linux/psp-platform-access.h (limited to 'include/linux/psp-platform-access.h') diff --git a/include/linux/psp-platform-access.h b/include/linux/psp-platform-access.h new file mode 100644 index 000000000000..977df5cfd494 --- /dev/null +++ b/include/linux/psp-platform-access.h @@ -0,0 +1,49 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#ifndef __PSP_PLATFORM_ACCESS_H +#define __PSP_PLATFORM_ACCESS_H + +#include + +enum psp_platform_access_msg { + PSP_CMD_NONE = 0x0, +}; + +struct psp_req_buffer_hdr { + u32 payload_size; + u32 status; +} __packed; + +struct psp_request { + struct psp_req_buffer_hdr header; + void *buf; +} __packed; + +/** + * psp_send_platform_access_msg() - Send a message to control platform features + * + * This function is intended to be used by drivers outside of ccp to communicate + * with the platform. + * + * Returns: + * 0: success + * -%EBUSY: mailbox in recovery or in use + * -%ENODEV: driver not bound with PSP device + * -%ETIMEDOUT: request timed out + * -%EIO: unknown error (see kernel log) + */ +int psp_send_platform_access_msg(enum psp_platform_access_msg, struct psp_request *req); + +/** + * psp_check_platform_access_status() - Checks whether platform features is ready + * + * This function is intended to be used by drivers outside of ccp to determine + * if platform features has initialized. + * + * Returns: + * 0 platform features is ready + * -%ENODEV platform features is not ready or present + */ +int psp_check_platform_access_status(void); + +#endif /* __PSP_PLATFORM_ACCESS_H */ -- cgit v1.2.3-70-g09d2 From d5812571f594b03438d0d7acd0dc044f73c1719e Mon Sep 17 00:00:00 2001 From: Mario Limonciello Date: Fri, 10 Mar 2023 15:19:50 -0600 Subject: crypto: ccp - Add support for ringing a platform doorbell Some platforms support using a doorbell to communicate. Export this feature for other drivers to utilize as well. Link: https://lore.kernel.org/linux-i2c/20220916131854.687371-3-jsd@semihalf.com/ Suggested-by: Jan Dabros Signed-off-by: Mario Limonciello Signed-off-by: Herbert Xu --- drivers/crypto/ccp/platform-access.c | 66 ++++++++++++++++++++++++++++++++++++ drivers/crypto/ccp/platform-access.h | 1 + drivers/crypto/ccp/sp-dev.h | 3 ++ drivers/crypto/ccp/sp-pci.c | 2 ++ include/linux/psp-platform-access.h | 15 ++++++++ include/linux/psp.h | 3 ++ 6 files changed, 90 insertions(+) (limited to 'include/linux/psp-platform-access.h') diff --git a/drivers/crypto/ccp/platform-access.c b/drivers/crypto/ccp/platform-access.c index 9cc0c60bbf7b..b51fb1196932 100644 --- a/drivers/crypto/ccp/platform-access.c +++ b/drivers/crypto/ccp/platform-access.c @@ -20,6 +20,14 @@ #define PSP_CMD_TIMEOUT_US (500 * USEC_PER_MSEC) +/* Doorbell shouldn't be ringing */ +static int check_doorbell(u32 __iomem *doorbell) +{ + u32 tmp; + + return readl_poll_timeout(doorbell, tmp, tmp != 0, 0, PSP_CMD_TIMEOUT_US); +} + /* Recovery field should be equal 0 to start sending commands */ static int check_recovery(u32 __iomem *cmd) { @@ -132,6 +140,62 @@ unlock: } EXPORT_SYMBOL_GPL(psp_send_platform_access_msg); +int psp_ring_platform_doorbell(int msg) +{ + struct psp_device *psp = psp_get_master_device(); + struct psp_platform_access_device *pa_dev; + u32 __iomem *button, *cmd; + int ret, val; + + if (!psp || !psp->platform_access_data) + return -ENODEV; + + pa_dev = psp->platform_access_data; + button = psp->io_regs + pa_dev->vdata->doorbell_button_reg; + cmd = psp->io_regs + pa_dev->vdata->doorbell_cmd_reg; + + mutex_lock(&pa_dev->doorbell_mutex); + + if (check_doorbell(button)) { + dev_dbg(psp->dev, "doorbell is not ready\n"); + ret = -EBUSY; + goto unlock; + } + + if (check_recovery(cmd)) { + dev_dbg(psp->dev, "doorbell command in recovery\n"); + ret = -EBUSY; + goto unlock; + } + + if (wait_cmd(cmd)) { + dev_dbg(psp->dev, "doorbell command not done processing\n"); + ret = -EBUSY; + goto unlock; + } + + iowrite32(FIELD_PREP(PSP_DRBL_MSG, msg), cmd); + iowrite32(PSP_DRBL_RING, button); + + if (wait_cmd(cmd)) { + ret = -ETIMEDOUT; + goto unlock; + } + + val = FIELD_GET(PSP_CMDRESP_STS, ioread32(cmd)); + if (val) { + ret = -EIO; + goto unlock; + } + + ret = 0; +unlock: + mutex_unlock(&pa_dev->doorbell_mutex); + + return ret; +} +EXPORT_SYMBOL_GPL(psp_ring_platform_doorbell); + void platform_access_dev_destroy(struct psp_device *psp) { struct psp_platform_access_device *pa_dev = psp->platform_access_data; @@ -140,6 +204,7 @@ void platform_access_dev_destroy(struct psp_device *psp) return; mutex_destroy(&pa_dev->mailbox_mutex); + mutex_destroy(&pa_dev->doorbell_mutex); psp->platform_access_data = NULL; } @@ -159,6 +224,7 @@ int platform_access_dev_init(struct psp_device *psp) pa_dev->vdata = (struct platform_access_vdata *)psp->vdata->platform_access; mutex_init(&pa_dev->mailbox_mutex); + mutex_init(&pa_dev->doorbell_mutex); dev_dbg(dev, "platform access enabled\n"); diff --git a/drivers/crypto/ccp/platform-access.h b/drivers/crypto/ccp/platform-access.h index c3a97893320d..a83f03beb869 100644 --- a/drivers/crypto/ccp/platform-access.h +++ b/drivers/crypto/ccp/platform-access.h @@ -24,6 +24,7 @@ struct psp_platform_access_device { struct platform_access_vdata *vdata; struct mutex mailbox_mutex; + struct mutex doorbell_mutex; void *platform_access_data; }; diff --git a/drivers/crypto/ccp/sp-dev.h b/drivers/crypto/ccp/sp-dev.h index 5ec6c219a731..1253a0217985 100644 --- a/drivers/crypto/ccp/sp-dev.h +++ b/drivers/crypto/ccp/sp-dev.h @@ -57,6 +57,9 @@ struct platform_access_vdata { const unsigned int cmdresp_reg; const unsigned int cmdbuff_addr_lo_reg; const unsigned int cmdbuff_addr_hi_reg; + const unsigned int doorbell_button_reg; + const unsigned int doorbell_cmd_reg; + }; struct psp_vdata { diff --git a/drivers/crypto/ccp/sp-pci.c b/drivers/crypto/ccp/sp-pci.c index 18aa902eb5ce..b5896f7af7ab 100644 --- a/drivers/crypto/ccp/sp-pci.c +++ b/drivers/crypto/ccp/sp-pci.c @@ -365,6 +365,8 @@ static const struct platform_access_vdata pa_v1 = { .cmdresp_reg = 0x10570, /* C2PMSG_28 */ .cmdbuff_addr_lo_reg = 0x10574, /* C2PMSG_29 */ .cmdbuff_addr_hi_reg = 0x10578, /* C2PMSG_30 */ + .doorbell_button_reg = 0x10a24, /* C2PMSG_73 */ + .doorbell_cmd_reg = 0x10a40, /* C2PMSG_80 */ }; static const struct psp_vdata pspv1 = { diff --git a/include/linux/psp-platform-access.h b/include/linux/psp-platform-access.h index 977df5cfd494..89df4549fada 100644 --- a/include/linux/psp-platform-access.h +++ b/include/linux/psp-platform-access.h @@ -34,6 +34,21 @@ struct psp_request { */ int psp_send_platform_access_msg(enum psp_platform_access_msg, struct psp_request *req); +/** + * psp_ring_platform_doorbell() - Ring platform doorbell + * + * This function is intended to be used by drivers outside of ccp to ring the + * platform doorbell with a message. + * + * Returns: + * 0: success + * -%EBUSY: mailbox in recovery or in use + * -%ENODEV: driver not bound with PSP device + * -%ETIMEDOUT: request timed out + * -%EIO: unknown error (see kernel log) + */ +int psp_ring_platform_doorbell(int msg); + /** * psp_check_platform_access_status() - Checks whether platform features is ready * diff --git a/include/linux/psp.h b/include/linux/psp.h index d3424790a70e..92e60aeef21e 100644 --- a/include/linux/psp.h +++ b/include/linux/psp.h @@ -23,4 +23,7 @@ #define PSP_CMDRESP_RECOVERY BIT(30) #define PSP_CMDRESP_RESP BIT(31) +#define PSP_DRBL_MSG PSP_CMDRESP_CMD +#define PSP_DRBL_RING BIT(0) + #endif /* __PSP_H */ -- cgit v1.2.3-70-g09d2 From a19c61b06585f71c4dc1303fe6a3af79dfe33678 Mon Sep 17 00:00:00 2001 From: Mario Limonciello Date: Mon, 3 Apr 2023 13:32:12 -0500 Subject: crypto: ccp - Return doorbell status code as an argument If the doorbell failed to ring we return -EIO, but the caller can't determine why it failed. Pass the reason for the failure in an argument for caller to investigate. Suggested-by: Mark Hasemeyer Signed-off-by: Mario Limonciello Reviewed-by: Mark Hasemeyer Tested-by: Mark Hasemeyer Signed-off-by: Herbert Xu --- drivers/crypto/ccp/platform-access.c | 4 +++- include/linux/psp-platform-access.h | 4 ++-- 2 files changed, 5 insertions(+), 3 deletions(-) (limited to 'include/linux/psp-platform-access.h') diff --git a/drivers/crypto/ccp/platform-access.c b/drivers/crypto/ccp/platform-access.c index 1cc154a1c6ab..48f59ae91692 100644 --- a/drivers/crypto/ccp/platform-access.c +++ b/drivers/crypto/ccp/platform-access.c @@ -132,7 +132,7 @@ unlock: } EXPORT_SYMBOL_GPL(psp_send_platform_access_msg); -int psp_ring_platform_doorbell(int msg) +int psp_ring_platform_doorbell(int msg, u32 *result) { struct psp_device *psp = psp_get_master_device(); struct psp_platform_access_device *pa_dev; @@ -164,6 +164,8 @@ int psp_ring_platform_doorbell(int msg) val = FIELD_GET(PSP_CMDRESP_STS, ioread32(cmd)); if (val) { + if (result) + *result = val; ret = -EIO; goto unlock; } diff --git a/include/linux/psp-platform-access.h b/include/linux/psp-platform-access.h index 89df4549fada..1b661341d8f3 100644 --- a/include/linux/psp-platform-access.h +++ b/include/linux/psp-platform-access.h @@ -45,9 +45,9 @@ int psp_send_platform_access_msg(enum psp_platform_access_msg, struct psp_reques * -%EBUSY: mailbox in recovery or in use * -%ENODEV: driver not bound with PSP device * -%ETIMEDOUT: request timed out - * -%EIO: unknown error (see kernel log) + * -%EIO: error will be stored in result argument */ -int psp_ring_platform_doorbell(int msg); +int psp_ring_platform_doorbell(int msg, u32 *result); /** * psp_check_platform_access_status() - Checks whether platform features is ready -- cgit v1.2.3-70-g09d2 From 440da737cf8d35a1b2205678cc1879fa90948f7a Mon Sep 17 00:00:00 2001 From: Mario Limonciello Date: Fri, 14 Apr 2023 09:40:07 -0500 Subject: i2c: designware: Use PCI PSP driver for communication Currently the PSP semaphore communication base address is discovered by using an MSR that is not architecturally guaranteed for future platforms. Also the mailbox that is utilized for communication with the PSP may have other consumers in the kernel, so it's better to make all communication go through a single driver. Signed-off-by: Mario Limonciello Reviewed-by: Mark Hasemeyer Acked-by: Jarkko Nikula Tested-by: Mark Hasemeyer Acked-by: Wolfram Sang Signed-off-by: Herbert Xu --- drivers/i2c/busses/Kconfig | 4 +- drivers/i2c/busses/i2c-designware-amdpsp.c | 175 ++++------------------------ drivers/i2c/busses/i2c-designware-core.h | 1 - drivers/i2c/busses/i2c-designware-platdrv.c | 1 - include/linux/psp-platform-access.h | 1 + 5 files changed, 29 insertions(+), 153 deletions(-) (limited to 'include/linux/psp-platform-access.h') diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index 25eb4e8fd22f..89f8b75043d0 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -566,9 +566,11 @@ config I2C_DESIGNWARE_PLATFORM config I2C_DESIGNWARE_AMDPSP bool "AMD PSP I2C semaphore support" - depends on X86_MSR depends on ACPI + depends on CRYPTO_DEV_SP_PSP depends on I2C_DESIGNWARE_PLATFORM + depends on (I2C_DESIGNWARE_PLATFORM=y && CRYPTO_DEV_CCP_DD=y) || \ + (I2C_DESIGNWARE_PLATFORM=m && CRYPTO_DEV_CCP_DD) help This driver enables managed host access to the selected I2C bus shared between AMD CPU and AMD PSP. diff --git a/drivers/i2c/busses/i2c-designware-amdpsp.c b/drivers/i2c/busses/i2c-designware-amdpsp.c index 652e6b64bd5f..12870dc44bdb 100644 --- a/drivers/i2c/busses/i2c-designware-amdpsp.c +++ b/drivers/i2c/busses/i2c-designware-amdpsp.c @@ -1,35 +1,20 @@ // SPDX-License-Identifier: GPL-2.0 -#include -#include #include -#include +#include #include -#include #include -#include - #include "i2c-designware-core.h" -#define MSR_AMD_PSP_ADDR 0xc00110a2 -#define PSP_MBOX_OFFSET 0x10570 -#define PSP_CMD_TIMEOUT_US (500 * USEC_PER_MSEC) - #define PSP_I2C_RESERVATION_TIME_MS 100 -#define PSP_I2C_REQ_BUS_CMD 0x64 #define PSP_I2C_REQ_RETRY_CNT 400 #define PSP_I2C_REQ_RETRY_DELAY_US (25 * USEC_PER_MSEC) #define PSP_I2C_REQ_STS_OK 0x0 #define PSP_I2C_REQ_STS_BUS_BUSY 0x1 #define PSP_I2C_REQ_STS_INV_PARAM 0x3 -struct psp_req_buffer_hdr { - u32 total_size; - u32 status; -}; - enum psp_i2c_req_type { PSP_I2C_REQ_ACQUIRE, PSP_I2C_REQ_RELEASE, @@ -41,119 +26,12 @@ struct psp_i2c_req { enum psp_i2c_req_type type; }; -struct psp_mbox { - u32 cmd_fields; - u64 i2c_req_addr; -} __packed; - static DEFINE_MUTEX(psp_i2c_access_mutex); static unsigned long psp_i2c_sem_acquired; -static void __iomem *mbox_iomem; static u32 psp_i2c_access_count; static bool psp_i2c_mbox_fail; static struct device *psp_i2c_dev; -/* - * Implementation of PSP-x86 i2c-arbitration mailbox introduced for AMD Cezanne - * family of SoCs. - */ - -static int psp_get_mbox_addr(unsigned long *mbox_addr) -{ - unsigned long long psp_mmio; - - if (rdmsrl_safe(MSR_AMD_PSP_ADDR, &psp_mmio)) - return -EIO; - - *mbox_addr = (unsigned long)(psp_mmio + PSP_MBOX_OFFSET); - - return 0; -} - -static int psp_mbox_probe(void) -{ - unsigned long mbox_addr; - int ret; - - ret = psp_get_mbox_addr(&mbox_addr); - if (ret) - return ret; - - mbox_iomem = ioremap(mbox_addr, sizeof(struct psp_mbox)); - if (!mbox_iomem) - return -ENOMEM; - - return 0; -} - -/* Recovery field should be equal 0 to start sending commands */ -static int psp_check_mbox_recovery(struct psp_mbox __iomem *mbox) -{ - u32 tmp; - - tmp = readl(&mbox->cmd_fields); - - return FIELD_GET(PSP_CMDRESP_RECOVERY, tmp); -} - -static int psp_wait_cmd(struct psp_mbox __iomem *mbox) -{ - u32 tmp, expected; - - /* Expect mbox_cmd to be cleared and the response bit to be set by PSP */ - expected = FIELD_PREP(PSP_CMDRESP_RESP, 1); - - /* - * Check for readiness of PSP mailbox in a tight loop in order to - * process further as soon as command was consumed. - */ - return readl_poll_timeout(&mbox->cmd_fields, tmp, (tmp == expected), - 0, PSP_CMD_TIMEOUT_US); -} - -/* Status equal to 0 means that PSP succeed processing command */ -static u32 psp_check_mbox_sts(struct psp_mbox __iomem *mbox) -{ - u32 cmd_reg; - - cmd_reg = readl(&mbox->cmd_fields); - - return FIELD_GET(PSP_CMDRESP_STS, cmd_reg); -} - -static int psp_send_cmd(struct psp_i2c_req *req) -{ - struct psp_mbox __iomem *mbox = mbox_iomem; - phys_addr_t req_addr; - u32 cmd_reg; - - if (psp_check_mbox_recovery(mbox)) - return -EIO; - - if (psp_wait_cmd(mbox)) - return -EBUSY; - - /* - * Fill mailbox with address of command-response buffer, which will be - * used for sending i2c requests as well as reading status returned by - * PSP. Use physical address of buffer, since PSP will map this region. - */ - req_addr = __psp_pa((void *)req); - writeq(req_addr, &mbox->i2c_req_addr); - - /* Write command register to trigger processing */ - cmd_reg = FIELD_PREP(PSP_CMDRESP_CMD, PSP_I2C_REQ_BUS_CMD); - writel(cmd_reg, &mbox->cmd_fields); - - if (psp_wait_cmd(mbox)) - return -ETIMEDOUT; - - if (psp_check_mbox_sts(mbox)) - return -EIO; - - return 0; -} - /* Helper to verify status returned by PSP */ static int check_i2c_req_sts(struct psp_i2c_req *req) { @@ -173,22 +51,25 @@ static int check_i2c_req_sts(struct psp_i2c_req *req) } } -static int psp_send_check_i2c_req(struct psp_i2c_req *req) +/* + * Errors in x86-PSP i2c-arbitration protocol may occur at two levels: + * 1. mailbox communication - PSP is not operational or some IO errors with + * basic communication had happened. + * 2. i2c-requests - PSP refuses to grant i2c arbitration to x86 for too long. + * + * In order to distinguish between these in error handling code all mailbox + * communication errors on the first level (from CCP symbols) will be passed + * up and if -EIO is returned the second level will be checked. + */ +static int psp_send_i2c_req_cezanne(struct psp_i2c_req *req) { - /* - * Errors in x86-PSP i2c-arbitration protocol may occur at two levels: - * 1. mailbox communication - PSP is not operational or some IO errors - * with basic communication had happened; - * 2. i2c-requests - PSP refuses to grant i2c arbitration to x86 for too - * long. - * In order to distinguish between these two in error handling code, all - * errors on the first level (returned by psp_send_cmd) are shadowed by - * -EIO. - */ - if (psp_send_cmd(req)) - return -EIO; + int ret; - return check_i2c_req_sts(req); + ret = psp_send_platform_access_msg(PSP_I2C_REQ_BUS_CMD, (struct psp_request *)req); + if (ret == -EIO) + return check_i2c_req_sts(req); + + return ret; } static int psp_send_i2c_req(enum psp_i2c_req_type i2c_req_type) @@ -202,11 +83,11 @@ static int psp_send_i2c_req(enum psp_i2c_req_type i2c_req_type) if (!req) return -ENOMEM; - req->hdr.total_size = sizeof(*req); + req->hdr.payload_size = sizeof(*req); req->type = i2c_req_type; start = jiffies; - ret = read_poll_timeout(psp_send_check_i2c_req, status, + ret = read_poll_timeout(psp_send_i2c_req_cezanne, status, (status != -EBUSY), PSP_I2C_REQ_RETRY_DELAY_US, PSP_I2C_REQ_RETRY_CNT * PSP_I2C_REQ_RETRY_DELAY_US, @@ -381,7 +262,8 @@ static const struct i2c_lock_operations i2c_dw_psp_lock_ops = { int i2c_dw_amdpsp_probe_lock_support(struct dw_i2c_dev *dev) { - int ret; + if (!IS_REACHABLE(CONFIG_CRYPTO_DEV_CCP_DD)) + return -ENODEV; if (!dev) return -ENODEV; @@ -393,11 +275,10 @@ int i2c_dw_amdpsp_probe_lock_support(struct dw_i2c_dev *dev) if (psp_i2c_dev) return -EEXIST; - psp_i2c_dev = dev->dev; + if (psp_check_platform_access_status()) + return -EPROBE_DEFER; - ret = psp_mbox_probe(); - if (ret) - return ret; + psp_i2c_dev = dev->dev; dev_info(psp_i2c_dev, "I2C bus managed by AMD PSP\n"); @@ -411,9 +292,3 @@ int i2c_dw_amdpsp_probe_lock_support(struct dw_i2c_dev *dev) return 0; } - -/* Unmap area used as a mailbox with PSP */ -void i2c_dw_amdpsp_remove_lock_support(struct dw_i2c_dev *dev) -{ - iounmap(mbox_iomem); -} diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h index 050d8c63ad3c..c5d87aae39c6 100644 --- a/drivers/i2c/busses/i2c-designware-core.h +++ b/drivers/i2c/busses/i2c-designware-core.h @@ -383,7 +383,6 @@ int i2c_dw_baytrail_probe_lock_support(struct dw_i2c_dev *dev); #if IS_ENABLED(CONFIG_I2C_DESIGNWARE_AMDPSP) int i2c_dw_amdpsp_probe_lock_support(struct dw_i2c_dev *dev); -void i2c_dw_amdpsp_remove_lock_support(struct dw_i2c_dev *dev); #endif int i2c_dw_validate_speed(struct dw_i2c_dev *dev); diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c index 74182db03a88..89ad88c54754 100644 --- a/drivers/i2c/busses/i2c-designware-platdrv.c +++ b/drivers/i2c/busses/i2c-designware-platdrv.c @@ -214,7 +214,6 @@ static const struct i2c_dw_semaphore_callbacks i2c_dw_semaphore_cb_table[] = { #ifdef CONFIG_I2C_DESIGNWARE_AMDPSP { .probe = i2c_dw_amdpsp_probe_lock_support, - .remove = i2c_dw_amdpsp_remove_lock_support, }, #endif {} diff --git a/include/linux/psp-platform-access.h b/include/linux/psp-platform-access.h index 1b661341d8f3..75da8f5f7ad8 100644 --- a/include/linux/psp-platform-access.h +++ b/include/linux/psp-platform-access.h @@ -7,6 +7,7 @@ enum psp_platform_access_msg { PSP_CMD_NONE = 0x0, + PSP_I2C_REQ_BUS_CMD = 0x64, }; struct psp_req_buffer_hdr { -- cgit v1.2.3-70-g09d2