From dc1cd6ed4b369aff26a10ecec2f65459fef043e9 Mon Sep 17 00:00:00 2001 From: Casey Connolly Date: Thu, 8 Jan 2026 21:28:46 +0100 Subject: [PATCH] soc/qcom: rpmh: add RPMh read Implement support for RPMh reads, these allow reading out the current votes for RPMh controlled resources such as regulators and interconnects. Link: https://patch.msgid.link/20260108-rpmh-regulator-fixes-v1-4-d1b5b300b665@linaro.org Signed-off-by: Casey Connolly --- drivers/soc/qcom/rpmh-rsc.c | 14 ++++++++++++-- drivers/soc/qcom/rpmh.c | 37 +++++++++++++++++++++++++++++++++++-- include/soc/qcom/rpmh.h | 4 +++- include/soc/qcom/tcs.h | 1 + 4 files changed, 51 insertions(+), 5 deletions(-) diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c index 05fff174f83..dce61f26229 100644 --- a/drivers/soc/qcom/rpmh-rsc.c +++ b/drivers/soc/qcom/rpmh-rsc.c @@ -282,12 +282,15 @@ static void __tcs_buffer_write(struct rsc_drv *drv, int tcs_id, int cmd_id, const struct tcs_request *msg) { u32 msgid; - u32 cmd_msgid = CMD_MSGID_LEN | CMD_MSGID_WRITE; + u32 cmd_msgid = CMD_MSGID_LEN; u32 cmd_enable = 0; u32 cmd_complete = 0; struct tcs_cmd *cmd; int i, j; + if (!msg->is_read) + cmd_msgid |= CMD_MSGID_WRITE; + if (msg->wait_for_compl) cmd_msgid |= CMD_MSGID_RESP_REQ; @@ -302,7 +305,8 @@ static void __tcs_buffer_write(struct rsc_drv *drv, int tcs_id, int cmd_id, write_tcs_cmd(drv, drv->regs[RSC_DRV_CMD_MSGID], tcs_id, j, msgid); write_tcs_cmd(drv, drv->regs[RSC_DRV_CMD_ADDR], tcs_id, j, cmd->addr); - write_tcs_cmd(drv, drv->regs[RSC_DRV_CMD_DATA], tcs_id, j, cmd->data); + if (!msg->is_read) + write_tcs_cmd(drv, drv->regs[RSC_DRV_CMD_DATA], tcs_id, j, cmd->data); debug("tcs(%d): [%s] cmd_id: %d: msgid: %#x addr: %#x data: %#x complete: %#x\n", tcs_id, msg->state == RPMH_ACTIVE_ONLY_STATE ? "active" : "?", j, msgid, cmd->addr, cmd->data, cmd_complete); @@ -418,6 +422,12 @@ int rpmh_rsc_send_data(struct rsc_drv *drv, const struct tcs_request *msg) udelay(1); } + /* U-Boot: read the response now we know it's available */ + if (msg->is_read) { + msg->cmds[0].data = read_tcs_cmd(drv, drv->regs[RSC_DRV_CMD_RESP_DATA], tcs_id, 0); + log_debug("data response: %#x\n", msg->cmds[0].data); + } + __tcs_set_trigger(drv, tcs_id, false); /* Reclaim the TCS */ diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c index 91b90626af3..8c222324c66 100644 --- a/drivers/soc/qcom/rpmh.c +++ b/drivers/soc/qcom/rpmh.c @@ -68,7 +68,7 @@ static int __rpmh_write(const struct udevice *dev, enum rpmh_state state, } static int __fill_rpmh_msg(struct rpmh_request *req, enum rpmh_state state, - const struct tcs_cmd *cmd, u32 n) + const struct tcs_cmd *cmd, u32 n, bool is_read) { if (!cmd || !n || n > MAX_RPMH_PAYLOAD) return -EINVAL; @@ -78,12 +78,45 @@ static int __fill_rpmh_msg(struct rpmh_request *req, enum rpmh_state state, req->msg.state = state; req->msg.cmds = req->cmd; req->msg.num_cmds = n; + req->msg.is_read = is_read; debug("rpmh_msg: %d, %d cmds [first %#x/%#x]\n", state, n, cmd->addr, cmd->data); return 0; } +/** + * rpmh_read: Read a resource value + * + * @dev: The device making the request + * @cmd: The payload having address of resource to read + * + * Reads the value for the resource address given in tcs_cmd->addr + * and returns the tcs_cmd->data filled with same. + * + * May sleep. Do not call from atomic contexts. + * + * Return: 0 on success, negative errno on failure + */ +int rpmh_read(const struct udevice *dev, enum rpmh_state state, struct tcs_cmd *cmd) +{ + DEFINE_RPMH_MSG_ONSTACK(dev, state, rpm_msg); + int ret; + + ret = __fill_rpmh_msg(&rpm_msg, state, cmd, 1, true); + if (ret) + return ret; + + ret = __rpmh_write(dev, state, &rpm_msg); + if (ret) + return ret; + + /* Read back the response into the cmd data structure */ + cmd->data = rpm_msg.cmd[0].data; + + return (ret > 0) ? 0 : ret; +} + /** * rpmh_write: Write a set of RPMH commands and block until response * @@ -100,7 +133,7 @@ int rpmh_write(const struct udevice *dev, enum rpmh_state state, DEFINE_RPMH_MSG_ONSTACK(dev, state, rpm_msg); int ret; - ret = __fill_rpmh_msg(&rpm_msg, state, cmd, n); + ret = __fill_rpmh_msg(&rpm_msg, state, cmd, n, false); if (ret) return ret; diff --git a/include/soc/qcom/rpmh.h b/include/soc/qcom/rpmh.h index 3421fbf1ee3..40812a315bc 100644 --- a/include/soc/qcom/rpmh.h +++ b/include/soc/qcom/rpmh.h @@ -13,12 +13,14 @@ #if IS_ENABLED(CONFIG_QCOM_RPMH) int rpmh_write(const struct udevice *dev, enum rpmh_state state, const struct tcs_cmd *cmd, u32 n); - +int rpmh_read(const struct udevice *dev, enum rpmh_state state, struct tcs_cmd *cmd); #else static inline int rpmh_write(const struct device *dev, enum rpmh_state state, const struct tcs_cmd *cmd, u32 n) { return -ENODEV; } +static inline int rpmh_read(const struct udevice *dev, struct tcs_cmd *cmd) +{ return -ENODEV; } #endif /* CONFIG_QCOM_RPMH */ diff --git a/include/soc/qcom/tcs.h b/include/soc/qcom/tcs.h index 3acca067c72..22bafe2598a 100644 --- a/include/soc/qcom/tcs.h +++ b/include/soc/qcom/tcs.h @@ -55,6 +55,7 @@ struct tcs_cmd { */ struct tcs_request { enum rpmh_state state; + bool is_read; u32 wait_for_compl; u32 num_cmds; struct tcs_cmd *cmds;