diff options
Diffstat (limited to 'src/soc/amd/picasso/smu.c')
-rw-r--r-- | src/soc/amd/picasso/smu.c | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/src/soc/amd/picasso/smu.c b/src/soc/amd/picasso/smu.c new file mode 100644 index 0000000000..cfe2240021 --- /dev/null +++ b/src/soc/amd/picasso/smu.c @@ -0,0 +1,90 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#include <timer.h> +#include <console/console.h> +#include <device/pci_ops.h> +#include <soc/pci_devs.h> +#include <soc/smu.h> +#include <types.h> + +static uint32_t smu_read32(uint32_t reg) +{ + pci_write_config32(SOC_GNB_DEV, SMU_INDEX_ADDR, reg); + return pci_read_config32(SOC_GNB_DEV, SMU_DATA_ADDR); +} + +static void smu_write32(uint32_t reg, uint32_t val) +{ + pci_write_config32(SOC_GNB_DEV, SMU_INDEX_ADDR, reg); + pci_write_config32(SOC_GNB_DEV, SMU_DATA_ADDR, val); +} + +#define SMU_MESG_RESP_TIMEOUT 0x00 +#define SMU_MESG_RESP_OK 0x01 + +/* returns SMU_MESG_RESP_OK, SMU_MESG_RESP_TIMEOUT or a negative number */ +static int32_t smu_poll_response(void) +{ + struct stopwatch sw; + const long timeout_ms = 10 * MSECS_PER_SEC; + int32_t result; + + stopwatch_init_msecs_expire(&sw, timeout_ms); + + do { + result = smu_read32(REG_ADDR_MESG_RESP); + if (result) { + printk(BIOS_SPEW, "SMU command consumed %ld msecs\n", + stopwatch_duration_usecs(&sw)); + return result; + } + } while (!stopwatch_expired(&sw)); + + printk(BIOS_ERR, "Error: timeout sending SMU message\n"); + return SMU_MESG_RESP_TIMEOUT; +} + +/* + * Send a message and bi-directional payload to the SMU. SMU response, if any, is returned via + * arg. + */ +enum cb_err send_smu_message(enum smu_message_id id, struct smu_payload *arg) +{ + size_t i; + + /* wait until SMU can process a new request; don't care if an old request failed */ + if (smu_poll_response() == SMU_MESG_RESP_TIMEOUT) + return CB_ERR; + + /* clear response register */ + smu_write32(REG_ADDR_MESG_RESP, 0); + + /* populate arguments */ + for (i = 0 ; i < SMU_NUM_ARGS ; i++) + smu_write32(REG_ADDR_MESG_ARG(i), arg->msg[i]); + + /* send message to SMU */ + smu_write32(REG_ADDR_MESG_ID, id); + + /* wait until SMU has processed the message and check if it was successful */ + if (smu_poll_response() != SMU_MESG_RESP_OK) + return CB_ERR; + + /* copy returned values */ + for (i = 0 ; i < SMU_NUM_ARGS ; i++) + arg->msg[i] = smu_read32(REG_ADDR_MESG_ARG(i)); + + return CB_SUCCESS; +} + +/* + * Request the SMU to put system into S3, S4, or S5. On entry, SlpTyp determines S-State and + * SlpTypeEn is clear. Function does not return if successful. + */ +void smu_sx_entry(void) +{ + struct smu_payload msg = { 0 }; /* Unused for SMC_MSG_S3ENTRY */ + + printk(BIOS_DEBUG, "SMU: Put system into S3/S4/S5\n"); + send_smu_message(SMC_MSG_S3ENTRY, &msg); +} |