@@ -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
@@ -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;
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@semihalf.com/ Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> --- 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(-)