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> --- v5->v6: * Handle Mendocino busy code like Cezanne 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 | 25 +++++++++++++++++++++- 2 files changed, 25 insertions(+), 1 deletion(-) 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 12870dc44bdb..f5c754919fbd 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> @@ -32,6 +33,8 @@ static u32 psp_i2c_access_count; static bool psp_i2c_mbox_fail; static struct device *psp_i2c_dev; +static int (*_psp_send_i2c_req)(struct psp_i2c_req *req); + /* Helper to verify status returned by PSP */ static int check_i2c_req_sts(struct psp_i2c_req *req) { @@ -72,6 +75,17 @@ static int psp_send_i2c_req_cezanne(struct psp_i2c_req *req) return ret; } +static int psp_send_i2c_req_mendocino(struct psp_i2c_req *req) +{ + int ret; + + ret = psp_ring_platform_doorbell(req->type, &req->hdr.status); + 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) { struct psp_i2c_req *req; @@ -87,7 +101,7 @@ static int psp_send_i2c_req(enum psp_i2c_req_type i2c_req_type) req->type = i2c_req_type; start = jiffies; - ret = read_poll_timeout(psp_send_i2c_req_cezanne, status, + ret = read_poll_timeout(_psp_send_i2c_req, status, (status != -EBUSY), PSP_I2C_REQ_RETRY_DELAY_US, PSP_I2C_REQ_RETRY_CNT * PSP_I2C_REQ_RETRY_DELAY_US, @@ -262,6 +276,8 @@ 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(CONFIG_CRYPTO_DEV_CCP_DD)) return -ENODEV; @@ -275,6 +291,13 @@ 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
