diff options
Diffstat (limited to 'drivers/gpu/drm/amd/amdgpu/amdgpu_ras_eeprom.c')
| -rw-r--r-- | drivers/gpu/drm/amd/amdgpu/amdgpu_ras_eeprom.c | 24 |
1 files changed, 21 insertions, 3 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ras_eeprom.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ras_eeprom.c index 7268ae65c140..1bb92a64f24a 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ras_eeprom.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ras_eeprom.c @@ -33,12 +33,30 @@ #include "amdgpu_reset.h" +/* These are memory addresses as would be seen by one or more EEPROM + * chips strung on the I2C bus, usually by manipulating pins 1-3 of a + * set of EEPROM devices. They form a continuous memory space. + * + * The I2C device address includes the device type identifier, 1010b, + * which is a reserved value and indicates that this is an I2C EEPROM + * device. It also includes the top 3 bits of the 19 bit EEPROM memory + * address, namely bits 18, 17, and 16. This makes up the 7 bit + * address sent on the I2C bus with bit 0 being the direction bit, + * which is not represented here, and sent by the hardware directly. + * + * For instance, + * 50h = 1010000b => device type identifier 1010b, bits 18:16 = 000b, address 0. + * 54h = 1010100b => --"--, bits 18:16 = 100b, address 40000h. + * 56h = 1010110b => --"--, bits 18:16 = 110b, address 60000h. + * Depending on the size of the I2C EEPROM device(s), bits 18:16 may + * address memory in a device or a device on the I2C bus, depending on + * the status of pins 1-3. See top of amdgpu_eeprom.c. + */ #define EEPROM_I2C_MADDR_VEGA20 0x0 #define EEPROM_I2C_MADDR_ARCTURUS 0x40000 #define EEPROM_I2C_MADDR_ARCTURUS_D342 0x0 #define EEPROM_I2C_MADDR_SIENNA_CICHLID 0x0 #define EEPROM_I2C_MADDR_ALDEBARAN 0x0 -#define EEPROM_I2C_MADDR_54H (0x54UL << 16) /* * The 2 macros bellow represent the actual size in bytes that @@ -130,7 +148,7 @@ static bool __get_eeprom_i2c_addr_ip_discovery(struct amdgpu_device *adev, switch (adev->ip_versions[MP1_HWIP][0]) { case IP_VERSION(13, 0, 0): case IP_VERSION(13, 0, 10): - control->i2c_address = EEPROM_I2C_MADDR_54H; + control->i2c_address = EEPROM_I2C_MADDR_ARCTURUS; return true; default: return false; @@ -185,7 +203,7 @@ static bool __get_eeprom_i2c_addr(struct amdgpu_device *adev, switch (adev->ip_versions[MP1_HWIP][0]) { case IP_VERSION(13, 0, 0): - control->i2c_address = EEPROM_I2C_MADDR_54H; + control->i2c_address = EEPROM_I2C_MADDR_ARCTURUS; break; default: |