diff options
-rw-r--r-- | drivers/soc/apple/Kconfig | 13 | ||||
-rw-r--r-- | drivers/soc/apple/Makefile | 3 | ||||
-rw-r--r-- | drivers/soc/apple/rtkit-crashlog.c | 154 | ||||
-rw-r--r-- | drivers/soc/apple/rtkit-internal.h | 62 | ||||
-rw-r--r-- | drivers/soc/apple/rtkit.c | 958 | ||||
-rw-r--r-- | include/linux/soc/apple/rtkit.h | 155 |
6 files changed, 1345 insertions, 0 deletions
diff --git a/drivers/soc/apple/Kconfig b/drivers/soc/apple/Kconfig index 9b8de31d6a8f..1b09037584a0 100644 --- a/drivers/soc/apple/Kconfig +++ b/drivers/soc/apple/Kconfig @@ -17,6 +17,19 @@ config APPLE_PMGR_PWRSTATE controls for SoC devices. This driver manages them through the generic power domain framework, and also provides reset support. +config APPLE_RTKIT + tristate "Apple RTKit co-processor IPC protocol" + depends on MAILBOX + depends on ARCH_APPLE || COMPILE_TEST + default ARCH_APPLE + help + Apple SoCs such as the M1 come with various co-processors running + their proprietary RTKit operating system. This option enables support + for the protocol library used to communicate with those. It is used + by various client drivers. + + Say 'y' here if you have an Apple SoC. + endmenu endif diff --git a/drivers/soc/apple/Makefile b/drivers/soc/apple/Makefile index c114e84667e4..8aca79fca0dd 100644 --- a/drivers/soc/apple/Makefile +++ b/drivers/soc/apple/Makefile @@ -1,2 +1,5 @@ # SPDX-License-Identifier: GPL-2.0-only obj-$(CONFIG_APPLE_PMGR_PWRSTATE) += apple-pmgr-pwrstate.o + +obj-$(CONFIG_APPLE_RTKIT) += apple-rtkit.o +apple-rtkit-y = rtkit.o rtkit-crashlog.o diff --git a/drivers/soc/apple/rtkit-crashlog.c b/drivers/soc/apple/rtkit-crashlog.c new file mode 100644 index 000000000000..732deed64660 --- /dev/null +++ b/drivers/soc/apple/rtkit-crashlog.c @@ -0,0 +1,154 @@ +// SPDX-License-Identifier: GPL-2.0-only OR MIT +/* + * Apple RTKit IPC library + * Copyright (C) The Asahi Linux Contributors + */ +#include "rtkit-internal.h" + +#define FOURCC(a, b, c, d) \ + (((u32)(a) << 24) | ((u32)(b) << 16) | ((u32)(c) << 8) | ((u32)(d))) + +#define APPLE_RTKIT_CRASHLOG_HEADER FOURCC('C', 'L', 'H', 'E') +#define APPLE_RTKIT_CRASHLOG_STR FOURCC('C', 's', 't', 'r') +#define APPLE_RTKIT_CRASHLOG_VERSION FOURCC('C', 'v', 'e', 'r') +#define APPLE_RTKIT_CRASHLOG_MBOX FOURCC('C', 'm', 'b', 'x') +#define APPLE_RTKIT_CRASHLOG_TIME FOURCC('C', 't', 'i', 'm') + +struct apple_rtkit_crashlog_header { + u32 fourcc; + u32 version; + u32 size; + u32 flags; + u8 _unk[16]; +}; +static_assert(sizeof(struct apple_rtkit_crashlog_header) == 0x20); + +struct apple_rtkit_crashlog_mbox_entry { + u64 msg0; + u64 msg1; + u32 timestamp; + u8 _unk[4]; +}; +static_assert(sizeof(struct apple_rtkit_crashlog_mbox_entry) == 0x18); + +static void apple_rtkit_crashlog_dump_str(struct apple_rtkit *rtk, u8 *bfr, + size_t size) +{ + u32 idx; + u8 *ptr, *end; + + memcpy(&idx, bfr, 4); + + ptr = bfr + 4; + end = bfr + size; + while (ptr < end) { + u8 *newline = memchr(ptr, '\n', end - ptr); + + if (newline) { + u8 tmp = *newline; + *newline = '\0'; + dev_warn(rtk->dev, "RTKit: Message (id=%x): %s\n", idx, + ptr); + *newline = tmp; + ptr = newline + 1; + } else { + dev_warn(rtk->dev, "RTKit: Message (id=%x): %s", idx, + ptr); + break; + } + } +} + +static void apple_rtkit_crashlog_dump_version(struct apple_rtkit *rtk, u8 *bfr, + size_t size) +{ + dev_warn(rtk->dev, "RTKit: Version: %s", bfr + 16); +} + +static void apple_rtkit_crashlog_dump_time(struct apple_rtkit *rtk, u8 *bfr, + size_t size) +{ + u64 crash_time; + + memcpy(&crash_time, bfr, 8); + dev_warn(rtk->dev, "RTKit: Crash time: %lld", crash_time); +} + +static void apple_rtkit_crashlog_dump_mailbox(struct apple_rtkit *rtk, u8 *bfr, + size_t size) +{ + u32 type, index, i; + size_t n_messages; + struct apple_rtkit_crashlog_mbox_entry entry; + + memcpy(&type, bfr + 16, 4); + memcpy(&index, bfr + 24, 4); + n_messages = (size - 28) / sizeof(entry); + + dev_warn(rtk->dev, "RTKit: Mailbox history (type = %d, index = %d)", + type, index); + for (i = 0; i < n_messages; ++i) { + memcpy(&entry, bfr + 28 + i * sizeof(entry), sizeof(entry)); + dev_warn(rtk->dev, "RTKit: #%03d@%08x: %016llx %016llx", i, + entry.timestamp, entry.msg0, entry.msg1); + } +} + +void apple_rtkit_crashlog_dump(struct apple_rtkit *rtk, u8 *bfr, size_t size) +{ + size_t offset; + u32 section_fourcc, section_size; + struct apple_rtkit_crashlog_header header; + + memcpy(&header, bfr, sizeof(header)); + if (header.fourcc != APPLE_RTKIT_CRASHLOG_HEADER) { + dev_warn(rtk->dev, "RTKit: Expected crashlog header but got %x", + header.fourcc); + return; + } + + if (header.size > size) { + dev_warn(rtk->dev, "RTKit: Crashlog size (%x) is too large", + header.size); + return; + } + + size = header.size; + offset = sizeof(header); + + while (offset < size) { + memcpy(§ion_fourcc, bfr + offset, 4); + memcpy(§ion_size, bfr + offset + 12, 4); + + switch (section_fourcc) { + case APPLE_RTKIT_CRASHLOG_HEADER: + dev_dbg(rtk->dev, "RTKit: End of crashlog reached"); + return; + case APPLE_RTKIT_CRASHLOG_STR: + apple_rtkit_crashlog_dump_str(rtk, bfr + offset + 16, + section_size); + break; + case APPLE_RTKIT_CRASHLOG_VERSION: + apple_rtkit_crashlog_dump_version( + rtk, bfr + offset + 16, section_size); + break; + case APPLE_RTKIT_CRASHLOG_MBOX: + apple_rtkit_crashlog_dump_mailbox( + rtk, bfr + offset + 16, section_size); + break; + case APPLE_RTKIT_CRASHLOG_TIME: + apple_rtkit_crashlog_dump_time(rtk, bfr + offset + 16, + section_size); + break; + default: + dev_warn(rtk->dev, + "RTKit: Unknown crashlog section: %x", + section_fourcc); + } + + offset += section_size; + } + + dev_warn(rtk->dev, + "RTKit: End of crashlog reached but no footer present"); +} diff --git a/drivers/soc/apple/rtkit-internal.h b/drivers/soc/apple/rtkit-internal.h new file mode 100644 index 000000000000..24bd619ec5e4 --- /dev/null +++ b/drivers/soc/apple/rtkit-internal.h @@ -0,0 +1,62 @@ +/* SPDX-License-Identifier: GPL-2.0-only OR MIT */ +/* + * Apple RTKit IPC library + * Copyright (C) The Asahi Linux Contributors + */ + +#ifndef _APPLE_RTKIT_INTERAL_H +#define _APPLE_RTKIT_INTERAL_H + +#include <linux/apple-mailbox.h> +#include <linux/bitfield.h> +#include <linux/bitmap.h> +#include <linux/completion.h> +#include <linux/dma-mapping.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/mailbox_client.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/soc/apple/rtkit.h> +#include <linux/workqueue.h> + +#define APPLE_RTKIT_APP_ENDPOINT_START 0x20 +#define APPLE_RTKIT_MAX_ENDPOINTS 0x100 + +struct apple_rtkit { + void *cookie; + const struct apple_rtkit_ops *ops; + struct device *dev; + + const char *mbox_name; + int mbox_idx; + struct mbox_client mbox_cl; + struct mbox_chan *mbox_chan; + + struct completion epmap_completion; + struct completion iop_pwr_ack_completion; + struct completion ap_pwr_ack_completion; + + int boot_result; + int version; + + unsigned int iop_power_state; + unsigned int ap_power_state; + bool crashed; + + DECLARE_BITMAP(endpoints, APPLE_RTKIT_MAX_ENDPOINTS); + + struct apple_rtkit_shmem ioreport_buffer; + struct apple_rtkit_shmem crashlog_buffer; + + struct apple_rtkit_shmem syslog_buffer; + char *syslog_msg_buffer; + size_t syslog_n_entries; + size_t syslog_msg_size; + + struct workqueue_struct *wq; +}; + +void apple_rtkit_crashlog_dump(struct apple_rtkit *rtk, u8 *bfr, size_t size); + +#endif diff --git a/drivers/soc/apple/rtkit.c b/drivers/soc/apple/rtkit.c new file mode 100644 index 000000000000..cf1129e9f76b --- /dev/null +++ b/drivers/soc/apple/rtkit.c @@ -0,0 +1,958 @@ +// SPDX-License-Identifier: GPL-2.0-only OR MIT +/* + * Apple RTKit IPC library + * Copyright (C) The Asahi Linux Contributors + */ + +#include "rtkit-internal.h" + +enum { + APPLE_RTKIT_PWR_STATE_OFF = 0x00, /* power off, cannot be restarted */ + APPLE_RTKIT_PWR_STATE_SLEEP = 0x01, /* sleeping, can be restarted */ + APPLE_RTKIT_PWR_STATE_QUIESCED = 0x10, /* running but no communication */ + APPLE_RTKIT_PWR_STATE_ON = 0x20, /* normal operating state */ +}; + +enum { + APPLE_RTKIT_EP_MGMT = 0, + APPLE_RTKIT_EP_CRASHLOG = 1, + APPLE_RTKIT_EP_SYSLOG = 2, + APPLE_RTKIT_EP_DEBUG = 3, + APPLE_RTKIT_EP_IOREPORT = 4, + APPLE_RTKIT_EP_OSLOG = 8, +}; + +#define APPLE_RTKIT_MGMT_TYPE GENMASK_ULL(59, 52) + +enum { + APPLE_RTKIT_MGMT_HELLO = 1, + APPLE_RTKIT_MGMT_HELLO_REPLY = 2, + APPLE_RTKIT_MGMT_STARTEP = 5, + APPLE_RTKIT_MGMT_SET_IOP_PWR_STATE = 6, + APPLE_RTKIT_MGMT_SET_IOP_PWR_STATE_ACK = 7, + APPLE_RTKIT_MGMT_EPMAP = 8, + APPLE_RTKIT_MGMT_EPMAP_REPLY = 8, + APPLE_RTKIT_MGMT_SET_AP_PWR_STATE = 0xb, + APPLE_RTKIT_MGMT_SET_AP_PWR_STATE_ACK = 0xb, +}; + +#define APPLE_RTKIT_MGMT_HELLO_MINVER GENMASK_ULL(15, 0) +#define APPLE_RTKIT_MGMT_HELLO_MAXVER GENMASK_ULL(31, 16) + +#define APPLE_RTKIT_MGMT_EPMAP_LAST BIT_ULL(51) +#define APPLE_RTKIT_MGMT_EPMAP_BASE GENMASK_ULL(34, 32) +#define APPLE_RTKIT_MGMT_EPMAP_BITMAP GENMASK_ULL(31, 0) + +#define APPLE_RTKIT_MGMT_EPMAP_REPLY_MORE BIT_ULL(0) + +#define APPLE_RTKIT_MGMT_STARTEP_EP GENMASK_ULL(39, 32) +#define APPLE_RTKIT_MGMT_STARTEP_FLAG BIT_ULL(1) + +#define APPLE_RTKIT_MGMT_PWR_STATE GENMASK_ULL(15, 0) + +#define APPLE_RTKIT_CRASHLOG_CRASH 1 + +#define APPLE_RTKIT_BUFFER_REQUEST 1 +#define APPLE_RTKIT_BUFFER_REQUEST_SIZE GENMASK_ULL(51, 44) +#define APPLE_RTKIT_BUFFER_REQUEST_IOVA GENMASK_ULL(41, 0) + +#define APPLE_RTKIT_SYSLOG_TYPE GENMASK_ULL(59, 52) + +#define APPLE_RTKIT_SYSLOG_LOG 5 + +#define APPLE_RTKIT_SYSLOG_INIT 8 +#define APPLE_RTKIT_SYSLOG_N_ENTRIES GENMASK_ULL(7, 0) +#define APPLE_RTKIT_SYSLOG_MSG_SIZE GENMASK_ULL(31, 24) + +#define APPLE_RTKIT_OSLOG_TYPE GENMASK_ULL(63, 56) +#define APPLE_RTKIT_OSLOG_INIT 1 +#define APPLE_RTKIT_OSLOG_ACK 3 + +#define APPLE_RTKIT_MIN_SUPPORTED_VERSION 11 +#define APPLE_RTKIT_MAX_SUPPORTED_VERSION 12 + +struct apple_rtkit_msg { + struct completion *completion; + struct apple_mbox_msg mbox_msg; +}; + +struct apple_rtkit_rx_work { + struct apple_rtkit *rtk; + u8 ep; + u64 msg; + struct work_struct work; +}; + +bool apple_rtkit_is_running(struct apple_rtkit *rtk) +{ + if (rtk->crashed) + return false; + if ((rtk->iop_power_state & 0xff) != APPLE_RTKIT_PWR_STATE_ON) + return false; + if ((rtk->ap_power_state & 0xff) != APPLE_RTKIT_PWR_STATE_ON) + return false; + return true; +} +EXPORT_SYMBOL_GPL(apple_rtkit_is_running); + +bool apple_rtkit_is_crashed(struct apple_rtkit *rtk) +{ + return rtk->crashed; +} +EXPORT_SYMBOL_GPL(apple_rtkit_is_crashed); + +static void apple_rtkit_management_send(struct apple_rtkit *rtk, u8 type, + u64 msg) +{ + msg &= ~APPLE_RTKIT_MGMT_TYPE; + msg |= FIELD_PREP(APPLE_RTKIT_MGMT_TYPE, type); + apple_rtkit_send_message(rtk, APPLE_RTKIT_EP_MGMT, msg, NULL, false); +} + +static void apple_rtkit_management_rx_hello(struct apple_rtkit *rtk, u64 msg) +{ + u64 reply; + + int min_ver = FIELD_GET(APPLE_RTKIT_MGMT_HELLO_MINVER, msg); + int max_ver = FIELD_GET(APPLE_RTKIT_MGMT_HELLO_MAXVER, msg); + int want_ver = min(APPLE_RTKIT_MAX_SUPPORTED_VERSION, max_ver); + + dev_dbg(rtk->dev, "RTKit: Min ver %d, max ver %d\n", min_ver, max_ver); + + if (min_ver > APPLE_RTKIT_MAX_SUPPORTED_VERSION) { + dev_err(rtk->dev, "RTKit: Firmware min version %d is too new\n", + min_ver); + goto abort_boot; + } + + if (max_ver < APPLE_RTKIT_MIN_SUPPORTED_VERSION) { + dev_err(rtk->dev, "RTKit: Firmware max version %d is too old\n", + max_ver); + goto abort_boot; + } + + dev_info(rtk->dev, "RTKit: Initializing (protocol version %d)\n", + want_ver); + rtk->version = want_ver; + + reply = FIELD_PREP(APPLE_RTKIT_MGMT_HELLO_MINVER, want_ver); + reply |= FIELD_PREP(APPLE_RTKIT_MGMT_HELLO_MAXVER, want_ver); + apple_rtkit_management_send(rtk, APPLE_RTKIT_MGMT_HELLO_REPLY, reply); + + return; + +abort_boot: + rtk->boot_result = -EINVAL; + complete_all(&rtk->epmap_completion); +} + +static void apple_rtkit_management_rx_epmap(struct apple_rtkit *rtk, u64 msg) +{ + int i, ep; + u64 reply; + unsigned long bitmap = FIELD_GET(APPLE_RTKIT_MGMT_EPMAP_BITMAP, msg); + u32 base = FIELD_GET(APPLE_RTKIT_MGMT_EPMAP_BASE, msg); + + dev_dbg(rtk->dev, + "RTKit: received endpoint bitmap 0x%lx with base 0x%x\n", + bitmap, base); + + for_each_set_bit(i, &bitmap, 32) { + ep = 32 * base + i; + dev_dbg(rtk->dev, "RTKit: Discovered endpoint 0x%02x\n", ep); + set_bit(ep, rtk->endpoints); + } + + reply = FIELD_PREP(APPLE_RTKIT_MGMT_EPMAP_BASE, base); + if (msg & APPLE_RTKIT_MGMT_EPMAP_LAST) + reply |= APPLE_RTKIT_MGMT_EPMAP_LAST; + else + reply |= APPLE_RTKIT_MGMT_EPMAP_REPLY_MORE; + + apple_rtkit_management_send(rtk, APPLE_RTKIT_MGMT_EPMAP_REPLY, reply); + + if (!(msg & APPLE_RTKIT_MGMT_EPMAP_LAST)) + return; + + for_each_set_bit(ep, rtk->endpoints, APPLE_RTKIT_APP_ENDPOINT_START) { + switch (ep) { + /* the management endpoint is started by default */ + case APPLE_RTKIT_EP_MGMT: + break; + + /* without starting these RTKit refuses to boot */ + case APPLE_RTKIT_EP_SYSLOG: + case APPLE_RTKIT_EP_CRASHLOG: + case APPLE_RTKIT_EP_DEBUG: + case APPLE_RTKIT_EP_IOREPORT: + case APPLE_RTKIT_EP_OSLOG: + dev_dbg(rtk->dev, + "RTKit: Starting system endpoint 0x%02x\n", ep); + apple_rtkit_start_ep(rtk, ep); + break; + + default: + dev_warn(rtk->dev, + "RTKit: Unknown system endpoint: 0x%02x\n", + ep); + } + } + + rtk->boot_result = 0; + complete_all(&rtk->epmap_completion); +} + +static void apple_rtkit_management_rx_iop_pwr_ack(struct apple_rtkit *rtk, + u64 msg) +{ + unsigned int new_state = FIELD_GET(APPLE_RTKIT_MGMT_PWR_STATE, msg); + + dev_dbg(rtk->dev, "RTKit: IOP power state transition: 0x%x -> 0x%x\n", + rtk->iop_power_state, new_state); + rtk->iop_power_state = new_state; + + complete_all(&rtk->iop_pwr_ack_completion); +} + +static void apple_rtkit_management_rx_ap_pwr_ack(struct apple_rtkit *rtk, + u64 msg) +{ + unsigned int new_state = FIELD_GET(APPLE_RTKIT_MGMT_PWR_STATE, msg); + + dev_dbg(rtk->dev, "RTKit: AP power state transition: 0x%x -> 0x%x\n", + rtk->ap_power_state, new_state); + rtk->ap_power_state = new_state; + + complete_all(&rtk->ap_pwr_ack_completion); +} + +static void apple_rtkit_management_rx(struct apple_rtkit *rtk, u64 msg) +{ + u8 type = FIELD_GET(APPLE_RTKIT_MGMT_TYPE, msg); + + switch (type) { + case APPLE_RTKIT_MGMT_HELLO: + apple_rtkit_management_rx_hello(rtk, msg); + break; + case APPLE_RTKIT_MGMT_EPMAP: + apple_rtkit_management_rx_epmap(rtk, msg); + break; + case APPLE_RTKIT_MGMT_SET_IOP_PWR_STATE_ACK: + apple_rtkit_management_rx_iop_pwr_ack(rtk, msg); + break; + case APPLE_RTKIT_MGMT_SET_AP_PWR_STATE_ACK: + apple_rtkit_management_rx_ap_pwr_ack(rtk, msg); + break; + default: + dev_warn( + rtk->dev, + "RTKit: unknown management message: 0x%llx (type: 0x%02x)\n", + msg, type); + } +} + +static int apple_rtkit_common_rx_get_buffer(struct apple_rtkit *rtk, + struct apple_rtkit_shmem *buffer, + u8 ep, u64 msg) +{ + size_t n_4kpages = FIELD_GET(APPLE_RTKIT_BUFFER_REQUEST_SIZE, msg); + u64 reply; + int err; + + buffer->buffer = NULL; + buffer->iomem = NULL; + buffer->is_mapped = false; + buffer->iova = FIELD_GET(APPLE_RTKIT_BUFFER_REQUEST_IOVA, msg); + buffer->size = n_4kpages << 12; + + dev_dbg(rtk->dev, "RTKit: buffer request for 0x%zx bytes at %pad\n", + buffer->size, &buffer->iova); + + if (buffer->iova && + (!rtk->ops->shmem_setup || !rtk->ops->shmem_destroy)) { + err = -EINVAL; + goto error; + } + + if (rtk->ops->shmem_setup) { + err = rtk->ops->shmem_setup(rtk->cookie, buffer); + if (err) + goto error; + } else { + buffer->buffer = dma_alloc_coherent(rtk->dev, buffer->size, + &buffer->iova, GFP_KERNEL); + if (!buffer->buffer) { + err = -ENOMEM; + goto error; + } + } + + if (!buffer->is_mapped) { + reply = FIELD_PREP(APPLE_RTKIT_SYSLOG_TYPE, + APPLE_RTKIT_BUFFER_REQUEST); + reply |= FIELD_PREP(APPLE_RTKIT_BUFFER_REQUEST_SIZE, n_4kpages); + reply |= FIELD_PREP(APPLE_RTKIT_BUFFER_REQUEST_IOVA, + buffer->iova); + apple_rtkit_send_message(rtk, ep, reply, NULL, false); + } + + return 0; + +error: + buffer->buffer = NULL; + buffer->iomem = NULL; + buffer->iova = 0; + buffer->size = 0; + buffer->is_mapped = false; + return err; +} + +static void apple_rtkit_free_buffer(struct apple_rtkit *rtk, + struct apple_rtkit_shmem *bfr) +{ + if (bfr->size == 0) + return; + + if (rtk->ops->shmem_destroy) + rtk->ops->shmem_destroy(rtk->cookie, bfr); + else if (bfr->buffer) + dma_free_coherent(rtk->dev, bfr->size, bfr->buffer, bfr->iova); + + bfr->buffer = NULL; + bfr->iomem = NULL; + bfr->iova = 0; + bfr->size = 0; + bfr->is_mapped = false; +} + +static void apple_rtkit_memcpy(struct apple_rtkit *rtk, void *dst, + struct apple_rtkit_shmem *bfr, size_t offset, + size_t len) +{ + if (bfr->iomem) + memcpy_fromio(dst, bfr->iomem + offset, len); + else + memcpy(dst, bfr->buffer + offset, len); +} + +static void apple_rtkit_crashlog_rx(struct apple_rtkit *rtk, u64 msg) +{ + u8 type = FIELD_GET(APPLE_RTKIT_SYSLOG_TYPE, msg); + u8 *bfr; + + if (type != APPLE_RTKIT_CRASHLOG_CRASH) { + dev_warn(rtk->dev, "RTKit: Unknown crashlog message: %llx\n", + msg); + return; + } + + if (!rtk->crashlog_buffer.size) { + apple_rtkit_common_rx_get_buffer(rtk, &rtk->crashlog_buffer, + APPLE_RTKIT_EP_CRASHLOG, msg); + return; + } + + dev_err(rtk->dev, "RTKit: co-processor has crashed\n"); + + /* + * create a shadow copy here to make sure the co-processor isn't able + * to change the log while we're dumping it. this also ensures + * the buffer is in normal memory and not iomem for e.g. the SMC + */ + bfr = kzalloc(rtk->crashlog_buffer.size, GFP_KERNEL); + if (bfr) { + apple_rtkit_memcpy(rtk, bfr, &rtk->crashlog_buffer, 0, + rtk->crashlog_buffer.size); + apple_rtkit_crashlog_dump(rtk, bfr, rtk->crashlog_buffer.size); + kfree(bfr); + } else { + dev_err(rtk->dev, + "RTKit: Couldn't allocate crashlog shadow buffer\n"); + } + + rtk->crashed = true; + if (rtk->ops->crashed) + rtk->ops->crashed(rtk->cookie); +} + +static void apple_rtkit_ioreport_rx(struct apple_rtkit *rtk, u64 msg) +{ + u8 type = FIELD_GET(APPLE_RTKIT_SYSLOG_TYPE, msg); + + switch (type) { + case APPLE_RTKIT_BUFFER_REQUEST: + apple_rtkit_common_rx_get_buffer(rtk, &rtk->ioreport_buffer, + APPLE_RTKIT_EP_IOREPORT, msg); + break; + /* unknown, must be ACKed or the co-processor will hang */ + case 0x8: + case 0xc: + apple_rtkit_send_message(rtk, APPLE_RTKIT_EP_IOREPORT, msg, + NULL, false); + break; + default: + dev_warn(rtk->dev, "RTKit: Unknown ioreport message: %llx\n", + msg); + } +} + +static void apple_rtkit_syslog_rx_init(struct apple_rtkit *rtk, u64 msg) +{ + rtk->syslog_n_entries = FIELD_GET(APPLE_RTKIT_SYSLOG_N_ENTRIES, msg); + rtk->syslog_msg_size = FIELD_GET(APPLE_RTKIT_SYSLOG_MSG_SIZE, msg); + + rtk->syslog_msg_buffer = kzalloc(rtk->syslog_msg_size, GFP_KERNEL); + + dev_dbg(rtk->dev, + "RTKit: syslog initialized: entries: %zd, msg_size: %zd\n", + rtk->syslog_n_entries, rtk->syslog_msg_size); +} + +static void apple_rtkit_syslog_rx_log(struct apple_rtkit *rtk, u64 msg) +{ + u8 idx = msg & 0xff; + char log_context[24]; + size_t entry_size = 0x20 + rtk->syslog_msg_size; + + if (!rtk->syslog_msg_buffer) { + dev_warn( + rtk->dev, + "RTKit: received syslog message but no syslog_msg_buffer\n"); + goto done; + } + if (!rtk->syslog_buffer.size) { + dev_warn( + rtk->dev, + "RTKit: received syslog message but syslog_buffer.size is zero\n"); + goto done; + } + if (!rtk->syslog_buffer.buffer && !rtk->syslog_buffer.iomem) { + dev_warn( + rtk->dev, + "RTKit: received syslog message but no syslog_buffer.buffer or syslog_buffer.iomem\n"); + goto done; + } + if (idx > rtk->syslog_n_entries) { + dev_warn(rtk->dev, "RTKit: syslog index %d out of range\n", + idx); + goto done; + } + + apple_rtkit_memcpy(rtk, log_context, &rtk->syslog_buffer, + idx * entry_size + 8, sizeof(log_context)); + apple_rtkit_memcpy(rtk, rtk->syslog_msg_buffer, &rtk->syslog_buffer, + idx * entry_size + 8 + sizeof(log_context), + rtk->syslog_msg_size); + + log_context[sizeof(log_context) - 1] = 0; + rtk->syslog_msg_buffer[rtk->syslog_msg_size - 1] = 0; + dev_info(rtk->dev, "RTKit: syslog message: %s: %s\n", log_context, + rtk->syslog_msg_buffer); + +done: + apple_rtkit_send_message(rtk, APPLE_RTKIT_EP_SYSLOG, msg, NULL, false); +} + +static void apple_rtkit_syslog_rx(struct apple_rtkit *rtk, u64 msg) +{ + u8 type = FIELD_GET(APPLE_RTKIT_SYSLOG_TYPE, msg); + + switch (type) { + case APPLE_RTKIT_BUFFER_REQUEST: + apple_rtkit_common_rx_get_buffer(rtk, &rtk->syslog_buffer, + APPLE_RTKIT_EP_SYSLOG, msg); + break; + case APPLE_RTKIT_SYSLOG_INIT: + apple_rtkit_syslog_rx_init(rtk, msg); + break; + case APPLE_RTKIT_SYSLOG_LOG: + apple_rtkit_syslog_rx_log(rtk, msg); + break; + default: + dev_warn(rtk->dev, "RTKit: Unknown syslog message: %llx\n", + msg); + } +} + +static void apple_rtkit_oslog_rx_init(struct apple_rtkit *rtk, u64 msg) +{ + u64 ack; + + dev_dbg(rtk->dev, "RTKit: oslog init: msg: 0x%llx\n", msg); + ack = FIELD_PREP(APPLE_RTKIT_OSLOG_TYPE, APPLE_RTKIT_OSLOG_ACK); + apple_rtkit_send_message(rtk, APPLE_RTKIT_EP_OSLOG, ack, NULL, false); +} + +static void apple_rtkit_oslog_rx(struct apple_rtkit *rtk, u64 msg) +{ + u8 type = FIELD_GET(APPLE_RTKIT_OSLOG_TYPE, msg); + + switch (type) { + case APPLE_RTKIT_OSLOG_INIT: + apple_rtkit_oslog_rx_init(rtk, msg); + break; + default: + dev_warn(rtk->dev, "RTKit: Unknown oslog message: %llx\n", msg); + } +} + +static void apple_rtkit_rx_work(struct work_struct *work) +{ + struct apple_rtkit_rx_work *rtk_work = + container_of(work, struct apple_rtkit_rx_work, work); + struct apple_rtkit *rtk = rtk_work->rtk; + + switch (rtk_work->ep) { + case APPLE_RTKIT_EP_MGMT: + apple_rtkit_management_rx(rtk, rtk_work->msg); + break; + case APPLE_RTKIT_EP_CRASHLOG: + apple_rtkit_crashlog_rx(rtk, rtk_work->msg); + break; + case APPLE_RTKIT_EP_SYSLOG: + apple_rtkit_syslog_rx(rtk, rtk_work->msg); + break; + case APPLE_RTKIT_EP_IOREPORT: + apple_rtkit_ioreport_rx(rtk, rtk_work->msg); + break; + case APPLE_RTKIT_EP_OSLOG: + apple_rtkit_oslog_rx(rtk, rtk_work->msg); + break; + case APPLE_RTKIT_APP_ENDPOINT_START ... 0xff: + if (rtk->ops->recv_message) + rtk->ops->recv_message(rtk->cookie, rtk_work->ep, + rtk_work->msg); + else + dev_warn( + rtk->dev, + "Received unexpected message to EP%02d: %llx\n", + rtk_work->ep, rtk_work->msg); + break; + default: + dev_warn(rtk->dev, + "RTKit: message to unknown endpoint %02x: %llx\n", + rtk_work->ep, rtk_work->msg); + } + + kfree(rtk_work); +} + +static void apple_rtkit_rx(struct mbox_client *cl, void *mssg) +{ + struct apple_rtkit *rtk = container_of(cl, struct apple_rtkit, mbox_cl); + struct apple_mbox_msg *msg = mssg; + struct apple_rtkit_rx_work *work; + u8 ep = msg->msg1; + + /* + * The message was read from a MMIO FIFO and we have to make + * sure all reads from buffers sent with that message happen + * afterwards. + */ + dma_rmb(); + + if (!test_bit(ep, rtk->endpoints)) + dev_warn(rtk->dev, + "RTKit: Message to undiscovered endpoint 0x%02x\n", + ep); + + if (ep >= APPLE_RTKIT_APP_ENDPOINT_START && + rtk->ops->recv_message_early && + rtk->ops->recv_message_early(rtk->cookie, ep, msg->msg0)) + return; + + work = kzalloc(sizeof(*work), GFP_ATOMIC); + if (!work) + return; + + work->rtk = rtk; + work->ep = ep; + work->msg = msg->msg0; + INIT_WORK(&work->work, apple_rtkit_rx_work); + queue_work(rtk->wq, &work->work); +} + +static void apple_rtkit_tx_done(struct mbox_client *cl, void *mssg, int r) +{ + struct apple_rtkit_msg *msg = + container_of(mssg, struct apple_rtkit_msg, mbox_msg); + + if (r == -ETIME) + return; + + if (msg->completion) + complete(msg->completion); + kfree(msg); +} + +int apple_rtkit_send_message(struct apple_rtkit *rtk, u8 ep, u64 message, + struct completion *completion, bool atomic) +{ + struct apple_rtkit_msg *msg; + int ret; + gfp_t flags; + + if (rtk->crashed) + return -EINVAL; + if (ep >= APPLE_RTKIT_APP_ENDPOINT_START && + !apple_rtkit_is_running(rtk)) + return -EINVAL; + + if (atomic) + flags = GFP_ATOMIC; + else + flags = GFP_KERNEL; + + msg = kzalloc(sizeof(*msg), flags); + if (!msg) + return -ENOMEM; + + msg->mbox_msg.msg0 = message; + msg->mbox_msg.msg1 = ep; + msg->completion = completion; + + /* + * The message will be sent with a MMIO write. We need the barrier + * here to ensure any previous writes to buffers are visible to the + * device before that MMIO write happens. + */ + dma_wmb(); + + ret = mbox_send_message(rtk->mbox_chan, &msg->mbox_msg); + if (ret < 0) { + kfree(msg); + return ret; + } + + return 0; +} +EXPORT_SYMBOL_GPL(apple_rtkit_send_message); + +int apple_rtkit_send_message_wait(struct apple_rtkit *rtk, u8 ep, u64 message, + unsigned long timeout, bool atomic) +{ + DECLARE_COMPLETION_ONSTACK(completion); + int ret; + long t; + + ret = apple_rtkit_send_message(rtk, ep, message, &completion, atomic); + if (ret < 0) + return ret; + + if (atomic) { + ret = mbox_flush(rtk->mbox_chan, timeout); + if (ret < 0) + return ret; + + if (try_wait_for_completion(&completion)) + return 0; + + return -ETIME; + } else { + t = wait_for_completion_interruptible_timeout( + &completion, msecs_to_jiffies(timeout)); + if (t < 0) + return t; + else if (t == 0) + return -ETIME; + return 0; + } +} +EXPORT_SYMBOL_GPL(apple_rtkit_send_message_wait); + +int apple_rtkit_start_ep(struct apple_rtkit *rtk, u8 endpoint) +{ + u64 msg; + + if (!test_bit(endpoint, rtk->endpoints)) + return -EINVAL; + if (endpoint >= APPLE_RTKIT_APP_ENDPOINT_START && + !apple_rtkit_is_running(rtk)) + return -EINVAL; + + msg = FIELD_PREP(APPLE_RTKIT_MGMT_STARTEP_EP, endpoint); + msg |= APPLE_RTKIT_MGMT_STARTEP_FLAG; + apple_rtkit_management_send(rtk, APPLE_RTKIT_MGMT_STARTEP, msg); + + return 0; +} +EXPORT_SYMBOL_GPL(apple_rtkit_start_ep); + +static int apple_rtkit_request_mbox_chan(struct apple_rtkit *rtk) +{ + if (rtk->mbox_name) + rtk->mbox_chan = mbox_request_channel_byname(&rtk->mbox_cl, + rtk->mbox_name); + else + rtk->mbox_chan = + mbox_request_channel(&rtk->mbox_cl, rtk->mbox_idx); + + if (IS_ERR(rtk->mbox_chan)) + return PTR_ERR(rtk->mbox_chan); + return 0; +} + +static struct apple_rtkit *apple_rtkit_init(struct device *dev, void *cookie, + const char *mbox_name, int mbox_idx, + const struct apple_rtkit_ops *ops) +{ + struct apple_rtkit *rtk; + int ret; + + if (!ops) + return ERR_PTR(-EINVAL); + + rtk = kzalloc(sizeof(*rtk), GFP_KERNEL); + if (!rtk) + return ERR_PTR(-ENOMEM); + + rtk->dev = dev; + rtk->cookie = cookie; + rtk->ops = ops; + + init_completion(&rtk->epmap_completion); + init_completion(&rtk->iop_pwr_ack_completion); + init_completion(&rtk->ap_pwr_ack_completion); + + bitmap_zero(rtk->endpoints, APPLE_RTKIT_MAX_ENDPOINTS); + set_bit(APPLE_RTKIT_EP_MGMT, rtk->endpoints); + + rtk->mbox_name = mbox_name; + rtk->mbox_idx = mbox_idx; + rtk->mbox_cl.dev = dev; + rtk->mbox_cl.tx_block = false; + rtk->mbox_cl.knows_txdone = false; + rtk->mbox_cl.rx_callback = &apple_rtkit_rx; + rtk->mbox_cl.tx_done = &apple_rtkit_tx_done; + + rtk->wq = alloc_ordered_workqueue("rtkit-%s", WQ_MEM_RECLAIM, + dev_name(rtk->dev)); + if (!rtk->wq) { + ret = -ENOMEM; + goto free_rtk; + } + + ret = apple_rtkit_request_mbox_chan(rtk); + if (ret) + goto destroy_wq; + + return rtk; + +destroy_wq: + destroy_workqueue(rtk->wq); +free_rtk: + kfree(rtk); + return ERR_PTR(ret); +} + +static int apple_rtkit_wait_for_completion(struct completion *c) +{ + long t; + + t = wait_for_completion_interruptible_timeout(c, + msecs_to_jiffies(1000)); + if (t < 0) + return t; + else if (t == 0) + return -ETIME; + else + return 0; +} + +int apple_rtkit_reinit(struct apple_rtkit *rtk) +{ + /* make sure we don't handle any messages while reinitializing */ + mbox_free_channel(rtk->mbox_chan); + flush_workqueue(rtk->wq); + + apple_rtkit_free_buffer(rtk, &rtk->ioreport_buffer); + apple_rtkit_free_buffer(rtk, &rtk->crashlog_buffer); + apple_rtkit_free_buffer(rtk, &rtk->syslog_buffer); + + kfree(rtk->syslog_msg_buffer); + + rtk->syslog_msg_buffer = NULL; + rtk->syslog_n_entries = 0; + rtk->syslog_msg_size = 0; + + bitmap_zero(rtk->endpoints, APPLE_RTKIT_MAX_ENDPOINTS); + set_bit(APPLE_RTKIT_EP_MGMT, rtk->endpoints); + + reinit_completion(&rtk->epmap_completion); + reinit_completion(&rtk->iop_pwr_ack_completion); + reinit_completion(&rtk->ap_pwr_ack_completion); + + rtk->crashed = false; + rtk->iop_power_state = APPLE_RTKIT_PWR_STATE_OFF; + rtk->ap_power_state = APPLE_RTKIT_PWR_STATE_OFF; + + return apple_rtkit_request_mbox_chan(rtk); +} +EXPORT_SYMBOL_GPL(apple_rtkit_reinit); + +static int apple_rtkit_set_ap_power_state(struct apple_rtkit *rtk, + unsigned int state) +{ + u64 msg; + int ret; + + reinit_completion(&rtk->ap_pwr_ack_completion); + + msg = FIELD_PREP(APPLE_RTKIT_MGMT_PWR_STATE, state); + apple_rtkit_management_send(rtk, APPLE_RTKIT_MGMT_SET_AP_PWR_STATE, + msg); + + ret = apple_rtkit_wait_for_completion(&rtk->ap_pwr_ack_completion); + if (ret) + return ret; + + if (rtk->ap_power_state != state) + return -EINVAL; + return 0; +} + +static int apple_rtkit_set_iop_power_state(struct apple_rtkit *rtk, + unsigned int state) +{ + u64 msg; + int ret; + + reinit_completion(&rtk->iop_pwr_ack_completion); + + msg = FIELD_PREP(APPLE_RTKIT_MGMT_PWR_STATE, state); + apple_rtkit_management_send(rtk, APPLE_RTKIT_MGMT_SET_IOP_PWR_STATE, + msg); + + ret = apple_rtkit_wait_for_completion(&rtk->iop_pwr_ack_completion); + if (ret) + return ret; + + if (rtk->iop_power_state != state) + return -EINVAL; + return 0; +} + +int apple_rtkit_boot(struct apple_rtkit *rtk) +{ + int ret; + + if (apple_rtkit_is_running(rtk)) + return 0; + if (rtk->crashed) + return -EINVAL; + + dev_dbg(rtk->dev, "RTKit: waiting for boot to finish\n"); + ret = apple_rtkit_wait_for_completion(&rtk->epmap_completion); + if (ret) + return ret; + if (rtk->boot_result) + return rtk->boot_result; + + dev_dbg(rtk->dev, "RTKit: waiting for IOP power state ACK\n"); + ret = apple_rtkit_wait_for_completion(&rtk->iop_pwr_ack_completion); + if (ret) + return ret; + + return apple_rtkit_set_ap_power_state(rtk, APPLE_RTKIT_PWR_STATE_ON); +} +EXPORT_SYMBOL_GPL(apple_rtkit_boot); + +int apple_rtkit_shutdown(struct apple_rtkit *rtk) +{ + int ret; + + /* if OFF is used here the co-processor will not wake up again */ + ret = apple_rtkit_set_ap_power_state(rtk, + APPLE_RTKIT_PWR_STATE_QUIESCED); + if (ret) + return ret; + + ret = apple_rtkit_set_iop_power_state(rtk, APPLE_RTKIT_PWR_STATE_SLEEP); + if (ret) + return ret; + + return apple_rtkit_reinit(rtk); +} +EXPORT_SYMBOL_GPL(apple_rtkit_shutdown); + +int apple_rtkit_quiesce(struct apple_rtkit *rtk) +{ + int ret; + + ret = apple_rtkit_set_ap_power_state(rtk, + APPLE_RTKIT_PWR_STATE_QUIESCED); + if (ret) + return ret; + + ret = apple_rtkit_set_iop_power_state(rtk, + APPLE_RTKIT_PWR_STATE_QUIESCED); + if (ret) + return ret; + + ret = apple_rtkit_reinit(rtk); + if (ret) + return ret; + + rtk->iop_power_state = APPLE_RTKIT_PWR_STATE_QUIESCED; + rtk->ap_power_state = APPLE_RTKIT_PWR_STATE_QUIESCED; + return 0; +} +EXPORT_SYMBOL_GPL(apple_rtkit_quiesce); + +int apple_rtkit_wake(struct apple_rtkit *rtk) +{ + u64 msg; + + if (apple_rtkit_is_running(rtk)) + return -EINVAL; + + reinit_completion(&rtk->iop_pwr_ack_completion); + + /* + * Use open-coded apple_rtkit_set_iop_power_state since apple_rtkit_boot + * will wait for the completion anyway. + */ + msg = FIELD_PREP(APPLE_RTKIT_MGMT_PWR_STATE, APPLE_RTKIT_PWR_STATE_ON); + apple_rtkit_management_send(rtk, APPLE_RTKIT_MGMT_SET_IOP_PWR_STATE, + msg); + + return apple_rtkit_boot(rtk); +} +EXPORT_SYMBOL_GPL(apple_rtkit_wake); + +static void apple_rtkit_free(struct apple_rtkit *rtk) +{ + mbox_free_channel(rtk->mbox_chan); + destroy_workqueue(rtk->wq); + + apple_rtkit_free_buffer(rtk, &rtk->ioreport_buffer); + apple_rtkit_free_buffer(rtk, &rtk->crashlog_buffer); + apple_rtkit_free_buffer(rtk, &rtk->syslog_buffer); + + kfree(rtk->syslog_msg_buffer); + kfree(rtk); +} + +struct apple_rtkit *devm_apple_rtkit_init(struct device *dev, void *cookie, + const char *mbox_name, int mbox_idx, + const struct apple_rtkit_ops *ops) +{ + struct apple_rtkit *rtk; + int ret; + + rtk = apple_rtkit_init(dev, cookie, mbox_name, mbox_idx, ops); + if (IS_ERR(rtk)) + return rtk; + + ret = devm_add_action_or_reset(dev, (void (*)(void *))apple_rtkit_free, + rtk); + if (ret) + return ERR_PTR(ret); + + return rtk; +} +EXPORT_SYMBOL_GPL(devm_apple_rtkit_init); + +MODULE_LICENSE("Dual MIT/GPL"); +MODULE_AUTHOR("Sven Peter <sven@svenpeter.dev>"); +MODULE_DESCRIPTION("Apple RTKit driver"); diff --git a/include/linux/soc/apple/rtkit.h b/include/linux/soc/apple/rtkit.h new file mode 100644 index 000000000000..88eb832eac7b --- /dev/null +++ b/include/linux/soc/apple/rtkit.h @@ -0,0 +1,155 @@ +/* SPDX-License-Identifier: GPL-2.0-only OR MIT */ +/* + * Apple RTKit IPC Library + * Copyright (C) The Asahi Linux Contributors + * + * Apple's SoCs come with various co-processors running their RTKit operating + * system. This protocol library is used by client drivers to use the + * features provided by them. + */ +#ifndef _LINUX_APPLE_RTKIT_H_ +#define _LINUX_APPLE_RTKIT_H_ + +#include <linux/device.h> +#include <linux/types.h> +#include <linux/mailbox_client.h> + +/* + * Struct to represent implementation-specific RTKit operations. + * + * @buffer: Shared memory buffer allocated inside normal RAM. + * @iomem: Shared memory buffer controlled by the co-processors. + * @size: Size of the shared memory buffer. + * @iova: Device VA of shared memory buffer. + * @is_mapped: Shared memory buffer is managed by the co-processor. + */ + +struct apple_rtkit_shmem { + void *buffer; + void __iomem *iomem; + size_t size; + dma_addr_t iova; + bool is_mapped; +}; + +/* + * Struct to represent implementation-specific RTKit operations. + * + * @crashed: Called when the co-processor has crashed. Runs in process + * context. + * @recv_message: Function called when a message from RTKit is received + * on a non-system endpoint. Called from a worker thread. + * @recv_message_early: + * Like recv_message, but called from atomic context. It + * should return true if it handled the message. If it + * returns false, the message will be passed on to the + * worker thread. + * @shmem_setup: Setup shared memory buffer. If bfr.is_iomem is true the + * buffer is managed by the co-processor and needs to be mapped. + * Otherwise the buffer is managed by Linux and needs to be + * allocated. If not specified dma_alloc_coherent is used. + * Called in process context. + * @shmem_destroy: Undo the shared memory buffer setup in shmem_setup. If not + * specified dma_free_coherent is used. Called in process + * context. + */ +struct apple_rtkit_ops { + void (*crashed)(void *cookie); + void (*recv_message)(void *cookie, u8 endpoint, u64 message); + bool (*recv_message_early)(void *cookie, u8 endpoint, u64 message); + int (*shmem_setup)(void *cookie, struct apple_rtkit_shmem *bfr); + void (*shmem_destroy)(void *cookie, struct apple_rtkit_shmem *bfr); +}; + +struct apple_rtkit; + +/* + * Initializes the internal state required to handle RTKit. This + * should usually be called within _probe. + * + * @dev: Pointer to the device node this coprocessor is assocated with + * @cookie: opaque cookie passed to all functions defined in rtkit_ops + * @mbox_name: mailbox name used to communicate with the co-processor + * @mbox_idx: mailbox index to be used if mbox_name is NULL + * @ops: pointer to rtkit_ops to be used for this co-processor + */ +struct apple_rtkit *devm_apple_rtkit_init(struct device *dev, void *cookie, + const char *mbox_name, int mbox_idx, + const struct apple_rtkit_ops *ops); + +/* + * Reinitialize internal structures. Must only be called with the co-processor + * is held in reset. + */ +int apple_rtkit_reinit(struct apple_rtkit *rtk); + +/* + * Handle RTKit's boot process. Should be called after the CPU of the + * co-processor has been started. + */ +int apple_rtkit_boot(struct apple_rtkit *rtk); + +/* + * Quiesce the co-processor. + */ +int apple_rtkit_quiesce(struct apple_rtkit *rtk); + +/* + * Wake the co-processor up from hibernation mode. + */ +int apple_rtkit_wake(struct apple_rtkit *rtk); + +/* + * Shutdown the co-processor + */ +int apple_rtkit_shutdown(struct apple_rtkit *rtk); + +/* + * Checks if RTKit is running and ready to handle messages. + */ +bool apple_rtkit_is_running(struct apple_rtkit *rtk); + +/* + * Checks if RTKit has crashed. + */ +bool apple_rtkit_is_crashed(struct apple_rtkit *rtk); + +/* + * Starts an endpoint. Must be called after boot but before any messages can be + * sent or received from that endpoint. + */ +int apple_rtkit_start_ep(struct apple_rtkit *rtk, u8 endpoint); + +/* + * Send a message to the given endpoint. + * + * @rtk: RTKit reference + * @ep: target endpoint + * @message: message to be sent + * @completeion: will be completed once the message has been submitted + * to the hardware FIFO. Can be NULL. + * @atomic: if set to true this function can be called from atomic + * context. + */ +int apple_rtkit_send_message(struct apple_rtkit *rtk, u8 ep, u64 message, + struct completion *completion, bool atomic); + +/* + * Send a message to the given endpoint and wait until it has been submitted + * to the hardware FIFO. + * Will return zero on success and a negative error code on failure + * (e.g. -ETIME when the message couldn't be written within the given + * timeout) + * + * @rtk: RTKit reference + * @ep: target endpoint + * @message: message to be sent + * @timeout: timeout in milliseconds to allow the message transmission + * to be completed + * @atomic: if set to true this function can be called from atomic + * context. + */ +int apple_rtkit_send_message_wait(struct apple_rtkit *rtk, u8 ep, u64 message, + unsigned long timeout, bool atomic); + +#endif /* _LINUX_APPLE_RTKIT_H_ */ |