From: Shyam Sundar S K Shyam-sundar.S-k@amd.com
[ Upstream commit 8d99129eef8f42377b41c1bacee9f8ce806e9f44 ]
The current SMN index used for the driver probe seems to be meant for the BIOS pair and there are potential concurrency problems that can occur with an inopportune SMI.
It is been advised to use SMN_INDEX_0 instead of SMN_INDEX_6, which is what amd_nb.c provides and this function has protections to ensure that only one caller can use it at a time.
Fixes: 426c0ff27b83 ("platform/x86: amd-pmc: Add support for AMD Smart Trace Buffer") Co-developed-by: Sanket Goswami Sanket.Goswami@amd.com Signed-off-by: Sanket Goswami Sanket.Goswami@amd.com Signed-off-by: Shyam Sundar S K Shyam-sundar.S-k@amd.com Link: https://lore.kernel.org/r/20230409185348.556161-7-Shyam-sundar.S-k@amd.com Reviewed-by: Hans de Goede hdegoede@redhat.com Signed-off-by: Hans de Goede hdegoede@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/platform/x86/amd/pmc.c | 26 ++++---------------------- 1 file changed, 4 insertions(+), 22 deletions(-)
diff --git a/drivers/platform/x86/amd/pmc.c b/drivers/platform/x86/amd/pmc.c index 2ecee810c960a..eb9fc6cb13e33 100644 --- a/drivers/platform/x86/amd/pmc.c +++ b/drivers/platform/x86/amd/pmc.c @@ -38,8 +38,6 @@ #define AMD_PMC_SCRATCH_REG_YC 0xD14
/* STB Registers */ -#define AMD_PMC_STB_INDEX_ADDRESS 0xF8 -#define AMD_PMC_STB_INDEX_DATA 0xFC #define AMD_PMC_STB_PMI_0 0x03E30600 #define AMD_PMC_STB_S2IDLE_PREPARE 0xC6000001 #define AMD_PMC_STB_S2IDLE_RESTORE 0xC6000002 @@ -897,17 +895,9 @@ static int amd_pmc_write_stb(struct amd_pmc_dev *dev, u32 data) { int err;
- err = pci_write_config_dword(dev->rdev, AMD_PMC_STB_INDEX_ADDRESS, AMD_PMC_STB_PMI_0); + err = amd_smn_write(0, AMD_PMC_STB_PMI_0, data); if (err) { - dev_err(dev->dev, "failed to write addr in stb: 0x%X\n", - AMD_PMC_STB_INDEX_ADDRESS); - return pcibios_err_to_errno(err); - } - - err = pci_write_config_dword(dev->rdev, AMD_PMC_STB_INDEX_DATA, data); - if (err) { - dev_err(dev->dev, "failed to write data in stb: 0x%X\n", - AMD_PMC_STB_INDEX_DATA); + dev_err(dev->dev, "failed to write data in stb: 0x%X\n", AMD_PMC_STB_PMI_0); return pcibios_err_to_errno(err); }
@@ -919,18 +909,10 @@ static int amd_pmc_read_stb(struct amd_pmc_dev *dev, u32 *buf) { int i, err;
- err = pci_write_config_dword(dev->rdev, AMD_PMC_STB_INDEX_ADDRESS, AMD_PMC_STB_PMI_0); - if (err) { - dev_err(dev->dev, "error writing addr to stb: 0x%X\n", - AMD_PMC_STB_INDEX_ADDRESS); - return pcibios_err_to_errno(err); - } - for (i = 0; i < FIFO_SIZE; i++) { - err = pci_read_config_dword(dev->rdev, AMD_PMC_STB_INDEX_DATA, buf++); + err = amd_smn_read(0, AMD_PMC_STB_PMI_0, buf++); if (err) { - dev_err(dev->dev, "error reading data from stb: 0x%X\n", - AMD_PMC_STB_INDEX_DATA); + dev_err(dev->dev, "error reading data from stb: 0x%X\n", AMD_PMC_STB_PMI_0); return pcibios_err_to_errno(err); } }