From: Richard Genoud <[email protected]> Introduce software IPC handshake between the host running Linux and the remote processors to gracefully stop/reset the remote core.
Upon a stop request, remoteproc driver sends a RP_MBOX_SHUTDOWN mailbox message to the remotecore. The remote core is expected to: - relinquish all the resources acquired through Device Manager (DM) - disable its interrupts - send back a mailbox acknowledgment RP_MBOX_SHUDOWN_ACK - enter WFI state. Meanwhile, the K3 remoteproc driver does: - wait for the RP_MBOX_SHUTDOWN_ACK from the remote core - wait for the remoteproc to enter WFI state - reset the remote core through device manager Based on work from: Hari Nagalla <[email protected]> Signed-off-by: Richard Genoud <[email protected]> [[email protected]: Extend support to all rprocs] Signed-off-by: Beleswar Padhi <[email protected]> --- v2: Changelog: 1. Extend graceful shutdown support for all rprocs (R5, DSP, M4) 2. Halt core only if SHUTDOWN_ACK is received from rproc and it has entered WFI state. 3. Convert return type of is_core_in_wfi() to bool. Works better with readx_poll_timeout() condition. 4. Cast RP_MBOX_SHUTDOWN to uintptr_t to suppress compiler warnings when void* is 64 bit. 5. Wrapped Graceful shutdown code in the form of notify_shutdown_rproc function. 6. Updated commit message to fix minor typos and such. Link to v1: https://lore.kernel.org/all/[email protected]/ Testing done: 1. Tested Boot across all TI K3 EVM/SK boards. 2. Tested IPC on all TI K3 J7* EVM/SK boards (& AM62x SK). 4. Tested R5 rprocs can now be shutdown and powered back on from userspace. 3. Tested that each patch in the series generates no new warnings/errors. drivers/remoteproc/omap_remoteproc.h | 9 ++- drivers/remoteproc/ti_k3_common.c | 72 +++++++++++++++++++++++ drivers/remoteproc/ti_k3_common.h | 4 ++ drivers/remoteproc/ti_k3_dsp_remoteproc.c | 2 + drivers/remoteproc/ti_k3_m4_remoteproc.c | 2 + drivers/remoteproc/ti_k3_r5_remoteproc.c | 5 ++ 6 files changed, 93 insertions(+), 1 deletion(-) diff --git a/drivers/remoteproc/omap_remoteproc.h b/drivers/remoteproc/omap_remoteproc.h index 828e13256c023..c008f11fa2a43 100644 --- a/drivers/remoteproc/omap_remoteproc.h +++ b/drivers/remoteproc/omap_remoteproc.h @@ -42,6 +42,11 @@ * @RP_MBOX_SUSPEND_CANCEL: a cancel suspend response from a remote processor * on a suspend request * + * @RP_MBOX_SHUTDOWN: shutdown request for the remote processor + * + * @RP_MBOX_SHUTDOWN_ACK: successful response from remote processor for a + * shutdown request. The remote processor should be in WFI state short after. + * * Introduce new message definitions if any here. * * @RP_MBOX_END_MSG: Indicates end of known/defined messages from remote core @@ -59,7 +64,9 @@ enum omap_rp_mbox_messages { RP_MBOX_SUSPEND_SYSTEM = 0xFFFFFF11, RP_MBOX_SUSPEND_ACK = 0xFFFFFF12, RP_MBOX_SUSPEND_CANCEL = 0xFFFFFF13, - RP_MBOX_END_MSG = 0xFFFFFF14, + RP_MBOX_SHUTDOWN = 0xFFFFFF14, + RP_MBOX_SHUTDOWN_ACK = 0xFFFFFF15, + RP_MBOX_END_MSG = 0xFFFFFF16, }; #endif /* _OMAP_RPMSG_H */ diff --git a/drivers/remoteproc/ti_k3_common.c b/drivers/remoteproc/ti_k3_common.c index 56b71652e449f..5d469f65115c3 100644 --- a/drivers/remoteproc/ti_k3_common.c +++ b/drivers/remoteproc/ti_k3_common.c @@ -18,7 +18,9 @@ * Hari Nagalla <[email protected]> */ +#include <linux/delay.h> #include <linux/io.h> +#include <linux/iopoll.h> #include <linux/mailbox_client.h> #include <linux/module.h> #include <linux/of_address.h> @@ -69,6 +71,10 @@ void k3_rproc_mbox_callback(struct mbox_client *client, void *data) case RP_MBOX_ECHO_REPLY: dev_info(dev, "received echo reply from %s\n", rproc->name); break; + case RP_MBOX_SHUTDOWN_ACK: + dev_dbg(dev, "received shutdown_ack from %s\n", rproc->name); + complete(&kproc->shutdown_complete); + break; default: /* silently handle all other valid messages */ if (msg >= RP_MBOX_READY && msg < RP_MBOX_END_MSG) @@ -188,6 +194,67 @@ int k3_rproc_request_mbox(struct rproc *rproc) } EXPORT_SYMBOL_GPL(k3_rproc_request_mbox); +/** + * is_core_in_wfi - Utility function to check core status + * @kproc: remote core pointer used for checking core status + * + * This utility function is invoked by the shutdown sequence to ensure + * the remote core is in wfi, before asserting a reset. + */ +bool is_core_in_wfi(struct k3_rproc *kproc) +{ + int ret; + u64 boot_vec; + u32 cfg, ctrl, stat; + + ret = ti_sci_proc_get_status(kproc->tsp, &boot_vec, &cfg, &ctrl, &stat); + if (ret) + return false; + + return (bool)(stat & PROC_BOOT_STATUS_FLAG_CPU_WFI); +} +EXPORT_SYMBOL_GPL(is_core_in_wfi); + +/** + * notify_shutdown_rproc - Prepare the remoteproc for a shutdown + * @kproc: remote core pointer used for sending mbox msg + * + * This function sends the shutdown prepare message to remote processor and + * waits for an ACK. Further, it checks if the remote processor has entered + * into WFI mode. It is invoked in shutdown sequence to ensure the rproc + * has relinquished its resources before asserting a reset, so the shutdown + * happens cleanly. + */ +int notify_shutdown_rproc(struct k3_rproc *kproc) +{ + bool wfi_status = false; + int ret; + + reinit_completion(&kproc->shutdown_complete); + + ret = mbox_send_message(kproc->mbox, (void *)(uintptr_t)RP_MBOX_SHUTDOWN); + if (ret < 0) { + dev_err(kproc->dev, "PM mbox_send_message failed: %d\n", ret); + return ret; + } + + ret = wait_for_completion_timeout(&kproc->shutdown_complete, + msecs_to_jiffies(5000)); + if (ret == 0) { + dev_err(kproc->dev, "%s: timeout waiting for rproc completion event\n", + __func__); + return -EBUSY; + } + + ret = readx_poll_timeout(is_core_in_wfi, kproc, wfi_status, wfi_status, + 200, 2000); + if (ret) + return ret; + + return 0; +} +EXPORT_SYMBOL_GPL(notify_shutdown_rproc); + /* * The K3 DSP and M4 cores have a local reset that affects only the CPU, and a * generic module reset that powers on the device and allows the internal @@ -288,6 +355,11 @@ EXPORT_SYMBOL_GPL(k3_rproc_start); int k3_rproc_stop(struct rproc *rproc) { struct k3_rproc *kproc = rproc->priv; + int ret; + + ret = notify_shutdown_rproc(kproc); + if (ret) + return ret; return k3_rproc_reset(kproc); } diff --git a/drivers/remoteproc/ti_k3_common.h b/drivers/remoteproc/ti_k3_common.h index aee3c28dbe510..2a025f4894b82 100644 --- a/drivers/remoteproc/ti_k3_common.h +++ b/drivers/remoteproc/ti_k3_common.h @@ -22,6 +22,7 @@ #define REMOTEPROC_TI_K3_COMMON_H #define KEYSTONE_RPROC_LOCAL_ADDRESS_MASK (SZ_16M - 1) +#define PROC_BOOT_STATUS_FLAG_CPU_WFI 0x00000002 /** * struct k3_rproc_mem - internal memory structure @@ -92,6 +93,7 @@ struct k3_rproc { u32 ti_sci_id; struct mbox_chan *mbox; struct mbox_client client; + struct completion shutdown_complete; void *priv; }; @@ -115,4 +117,6 @@ int k3_rproc_of_get_memories(struct platform_device *pdev, void k3_mem_release(void *data); int k3_reserved_mem_init(struct k3_rproc *kproc); void k3_release_tsp(void *data); +bool is_core_in_wfi(struct k3_rproc *kproc); +int notify_shutdown_rproc(struct k3_rproc *kproc); #endif /* REMOTEPROC_TI_K3_COMMON_H */ diff --git a/drivers/remoteproc/ti_k3_dsp_remoteproc.c b/drivers/remoteproc/ti_k3_dsp_remoteproc.c index d6ceea6dc920e..156ae09d8ee25 100644 --- a/drivers/remoteproc/ti_k3_dsp_remoteproc.c +++ b/drivers/remoteproc/ti_k3_dsp_remoteproc.c @@ -133,6 +133,8 @@ static int k3_dsp_rproc_probe(struct platform_device *pdev) if (ret) return ret; + init_completion(&kproc->shutdown_complete); + ret = k3_rproc_of_get_memories(pdev, kproc); if (ret) return ret; diff --git a/drivers/remoteproc/ti_k3_m4_remoteproc.c b/drivers/remoteproc/ti_k3_m4_remoteproc.c index 3a11fd24eb52b..64d99071279b0 100644 --- a/drivers/remoteproc/ti_k3_m4_remoteproc.c +++ b/drivers/remoteproc/ti_k3_m4_remoteproc.c @@ -90,6 +90,8 @@ static int k3_m4_rproc_probe(struct platform_device *pdev) if (ret) return ret; + init_completion(&kproc->shutdown_complete); + ret = k3_rproc_of_get_memories(pdev, kproc); if (ret) return ret; diff --git a/drivers/remoteproc/ti_k3_r5_remoteproc.c b/drivers/remoteproc/ti_k3_r5_remoteproc.c index 04f23295ffc10..8748dc6089cc2 100644 --- a/drivers/remoteproc/ti_k3_r5_remoteproc.c +++ b/drivers/remoteproc/ti_k3_r5_remoteproc.c @@ -533,6 +533,10 @@ static int k3_r5_rproc_stop(struct rproc *rproc) struct k3_r5_cluster *cluster = core->cluster; int ret; + ret = notify_shutdown_rproc(kproc); + if (ret) + return ret; + /* halt all applicable cores */ if (cluster->mode == CLUSTER_MODE_LOCKSTEP) { list_for_each_entry(core, &cluster->cores, elem) { @@ -1129,6 +1133,7 @@ static int k3_r5_cluster_rproc_init(struct platform_device *pdev) goto out; } + init_completion(&kproc->shutdown_complete); init_rmem: k3_r5_adjust_tcm_sizes(kproc); -- 2.34.1
