Mendocino and later platform don't use the platform feature mailbox for communication for I2C arbitration, they rely upon ringing a doorbell. Detect the platform by the device ID of the root port and choose the appropriate method. Link: https://lore.kernel.org/linux-i2c/20220916131854.687371-3-jsd@xxxxxxxxxxxx/ Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx> --- v4->v5: * Poll for busy * Rename to mendocino * Add explicit dependency on PCI v3->v4: * Adjust to use PCI device ID and function pointers instead v2->v3: * Use CPU ID rather than ACPI ID, this will be pushed to a later patch v1->v2: * New patch --- drivers/i2c/busses/Kconfig | 1 + drivers/i2c/busses/i2c-designware-amdpsp.c | 52 +++++++++++++++++----- 2 files changed, 43 insertions(+), 10 deletions(-) diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index d53bf716f97d..2aba5ffa8b03 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -568,6 +568,7 @@ config I2C_DESIGNWARE_AMDPSP bool "AMD PSP I2C semaphore support" depends on ACPI depends on I2C_DESIGNWARE_PLATFORM + depends on PCI imply CRYPTO_DEV_SP_PSP help This driver enables managed host access to the selected I2C bus shared diff --git a/drivers/i2c/busses/i2c-designware-amdpsp.c b/drivers/i2c/busses/i2c-designware-amdpsp.c index 105584abcf8f..87b6cc345d1d 100644 --- a/drivers/i2c/busses/i2c-designware-amdpsp.c +++ b/drivers/i2c/busses/i2c-designware-amdpsp.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: GPL-2.0 #include <linux/i2c.h> +#include <linux/pci.h> #include <linux/psp-platform-access.h> #include <linux/psp.h> #include <linux/workqueue.h> @@ -36,6 +37,8 @@ static u32 psp_i2c_access_count; static bool psp_i2c_mbox_fail; static struct device *psp_i2c_dev; +static int (*_psp_send_i2c_req)(enum psp_i2c_req_type); + /* Helper to verify status returned by PSP */ static int check_i2c_req_sts(struct psp_i2c_req *req) { @@ -73,34 +76,55 @@ static int psp_send_check_i2c_req(struct psp_i2c_req *req) return check_i2c_req_sts(req); } -static int psp_send_i2c_req(enum psp_i2c_req_type i2c_req_type) +static int psp_send_i2c_req_cezanne(enum psp_i2c_req_type i2c_req_type) { struct psp_i2c_req *req; - unsigned long start; int status, ret; /* Allocate command-response buffer */ req = kzalloc(sizeof(*req), GFP_KERNEL); if (!req) return -ENOMEM; - req->hdr.payload_size = sizeof(*req); req->type = i2c_req_type; - - start = jiffies; ret = read_poll_timeout(psp_send_check_i2c_req, status, (status != -EBUSY), PSP_I2C_REQ_RETRY_DELAY_US, PSP_I2C_REQ_RETRY_CNT * PSP_I2C_REQ_RETRY_DELAY_US, 0, req); - if (ret) { + kfree(req); + + if (ret) dev_err(psp_i2c_dev, "Timed out waiting for PSP to %s I2C bus\n", (i2c_req_type == PSP_I2C_REQ_ACQUIRE) ? "release" : "acquire"); - goto cleanup; - } - ret = status; + return ret ? ret : status; +} + +static int psp_send_i2c_req_mendocino(enum psp_i2c_req_type i2c_req_type) +{ + int status, ret; + + ret = read_poll_timeout(psp_ring_platform_doorbell, status, + (status != -EBUSY), + PSP_I2C_REQ_RETRY_DELAY_US, + PSP_I2C_REQ_RETRY_CNT * PSP_I2C_REQ_RETRY_DELAY_US, + 0, i2c_req_type); + if (ret) + dev_err(psp_i2c_dev, "Timed out waiting for PSP to %s I2C bus\n", + (i2c_req_type == PSP_I2C_REQ_ACQUIRE) ? + "release" : "acquire"); + + return ret ? ret : status; +} + +static int psp_send_i2c_req(enum psp_i2c_req_type i2c_req_type) +{ + unsigned long start = jiffies; + int ret; + + ret = _psp_send_i2c_req(i2c_req_type); if (ret) { dev_err(psp_i2c_dev, "PSP communication error\n"); goto cleanup; @@ -115,7 +139,6 @@ static int psp_send_i2c_req(enum psp_i2c_req_type i2c_req_type) psp_i2c_mbox_fail = true; } - kfree(req); return ret; } @@ -263,6 +286,8 @@ static const struct i2c_lock_operations i2c_dw_psp_lock_ops = { int i2c_dw_amdpsp_probe_lock_support(struct dw_i2c_dev *dev) { + struct pci_dev *rdev; + if (!IS_REACHABLE(CRYPTO_DEV_CCP_DD)) return -ENODEV; @@ -276,6 +301,13 @@ int i2c_dw_amdpsp_probe_lock_support(struct dw_i2c_dev *dev) if (psp_i2c_dev) return -EEXIST; + /* Cezanne uses platform mailbox, Mendocino and later use doorbell */ + rdev = pci_get_domain_bus_and_slot(0, 0, PCI_DEVFN(0, 0)); + if (rdev->device == 0x1630) + _psp_send_i2c_req = psp_send_i2c_req_cezanne; + else + _psp_send_i2c_req = psp_send_i2c_req_mendocino; + if (psp_check_platform_access_status()) return -EPROBE_DEFER; -- 2.34.1
