diff options
Diffstat (limited to 'include/linux/cs5535.h')
-rw-r--r-- | include/linux/cs5535.h | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/include/linux/cs5535.h b/include/linux/cs5535.h index 39e93e8ed95d..eb34108a608b 100644 --- a/include/linux/cs5535.h +++ b/include/linux/cs5535.h @@ -36,6 +36,38 @@ #define LBAR_ACPI_SIZE 0x40 #define LBAR_PMS_SIZE 0x80 +/* VSA2 magic values */ +#define VSA_VRC_INDEX 0xAC1C +#define VSA_VRC_DATA 0xAC1E +#define VSA_VR_UNLOCK 0xFC53 /* unlock virtual register */ +#define VSA_VR_SIGNATURE 0x0003 +#define VSA_VR_MEM_SIZE 0x0200 +#define AMD_VSA_SIG 0x4132 /* signature is ascii 'VSA2' */ +#define GSW_VSA_SIG 0x534d /* General Software signature */ + +#include <linux/io.h> + +static inline int cs5535_has_vsa2(void) +{ + static int has_vsa2 = -1; + + if (has_vsa2 == -1) { + uint16_t val; + + /* + * The VSA has virtual registers that we can query for a + * signature. + */ + outw(VSA_VR_UNLOCK, VSA_VRC_INDEX); + outw(VSA_VR_SIGNATURE, VSA_VRC_INDEX); + + val = inw(VSA_VRC_DATA); + has_vsa2 = (val == AMD_VSA_SIG || val == GSW_VSA_SIG); + } + + return has_vsa2; +} + /* GPIOs */ #define GPIO_OUTPUT_VAL 0x00 #define GPIO_OUTPUT_ENABLE 0x04 |