diff options
Diffstat (limited to 'drivers/gpu/drm/xe/xe_pcode.c')
| -rw-r--r-- | drivers/gpu/drm/xe/xe_pcode.c | 296 |
1 files changed, 296 insertions, 0 deletions
diff --git a/drivers/gpu/drm/xe/xe_pcode.c b/drivers/gpu/drm/xe/xe_pcode.c new file mode 100644 index 000000000000..b324dc2a5deb --- /dev/null +++ b/drivers/gpu/drm/xe/xe_pcode.c @@ -0,0 +1,296 @@ +// SPDX-License-Identifier: MIT +/* + * Copyright © 2022 Intel Corporation + */ + +#include "xe_pcode.h" + +#include <linux/delay.h> +#include <linux/errno.h> + +#include <drm/drm_managed.h> + +#include "xe_gt.h" +#include "xe_mmio.h" +#include "xe_pcode_api.h" + +/** + * DOC: PCODE + * + * Xe PCODE is the component responsible for interfacing with the PCODE + * firmware. + * It shall provide a very simple ABI to other Xe components, but be the + * single and consolidated place that will communicate with PCODE. All read + * and write operations to PCODE will be internal and private to this component. + * + * What's next: + * - PCODE hw metrics + * - PCODE for display operations + */ + +static int pcode_mailbox_status(struct xe_gt *gt) +{ + u32 err; + static const struct pcode_err_decode err_decode[] = { + [PCODE_ILLEGAL_CMD] = {-ENXIO, "Illegal Command"}, + [PCODE_TIMEOUT] = {-ETIMEDOUT, "Timed out"}, + [PCODE_ILLEGAL_DATA] = {-EINVAL, "Illegal Data"}, + [PCODE_ILLEGAL_SUBCOMMAND] = {-ENXIO, "Illegal Subcommand"}, + [PCODE_LOCKED] = {-EBUSY, "PCODE Locked"}, + [PCODE_GT_RATIO_OUT_OF_RANGE] = {-EOVERFLOW, + "GT ratio out of range"}, + [PCODE_REJECTED] = {-EACCES, "PCODE Rejected"}, + [PCODE_ERROR_MASK] = {-EPROTO, "Unknown"}, + }; + + lockdep_assert_held(>->pcode.lock); + + err = xe_mmio_read32(gt, PCODE_MAILBOX) & PCODE_ERROR_MASK; + if (err) { + drm_err(>_to_xe(gt)->drm, "PCODE Mailbox failed: %d %s", err, + err_decode[err].str ?: "Unknown"); + return err_decode[err].errno ?: -EPROTO; + } + + return 0; +} + +static int pcode_mailbox_rw(struct xe_gt *gt, u32 mbox, u32 *data0, u32 *data1, + unsigned int timeout_ms, bool return_data, + bool atomic) +{ + int err; + + if (gt_to_xe(gt)->info.skip_pcode) + return 0; + + lockdep_assert_held(>->pcode.lock); + + if ((xe_mmio_read32(gt, PCODE_MAILBOX) & PCODE_READY) != 0) + return -EAGAIN; + + xe_mmio_write32(gt, PCODE_DATA0, *data0); + xe_mmio_write32(gt, PCODE_DATA1, data1 ? *data1 : 0); + xe_mmio_write32(gt, PCODE_MAILBOX, PCODE_READY | mbox); + + err = xe_mmio_wait32(gt, PCODE_MAILBOX, PCODE_READY, 0, + timeout_ms * 1000, NULL, atomic); + if (err) + return err; + + if (return_data) { + *data0 = xe_mmio_read32(gt, PCODE_DATA0); + if (data1) + *data1 = xe_mmio_read32(gt, PCODE_DATA1); + } + + return pcode_mailbox_status(gt); +} + +int xe_pcode_write_timeout(struct xe_gt *gt, u32 mbox, u32 data, int timeout) +{ + int err; + + mutex_lock(>->pcode.lock); + err = pcode_mailbox_rw(gt, mbox, &data, NULL, timeout, false, false); + mutex_unlock(>->pcode.lock); + + return err; +} + +int xe_pcode_read(struct xe_gt *gt, u32 mbox, u32 *val, u32 *val1) +{ + int err; + + mutex_lock(>->pcode.lock); + err = pcode_mailbox_rw(gt, mbox, val, val1, 1, true, false); + mutex_unlock(>->pcode.lock); + + return err; +} + +static int xe_pcode_try_request(struct xe_gt *gt, u32 mbox, + u32 request, u32 reply_mask, u32 reply, + u32 *status, bool atomic, int timeout_us) +{ + int slept, wait = 10; + + for (slept = 0; slept < timeout_us; slept += wait) { + *status = pcode_mailbox_rw(gt, mbox, &request, NULL, 1, true, + atomic); + if ((*status == 0) && ((request & reply_mask) == reply)) + return 0; + + if (atomic) + udelay(wait); + else + usleep_range(wait, wait << 1); + wait <<= 1; + } + + return -ETIMEDOUT; +} + +/** + * xe_pcode_request - send PCODE request until acknowledgment + * @gt: gt + * @mbox: PCODE mailbox ID the request is targeted for + * @request: request ID + * @reply_mask: mask used to check for request acknowledgment + * @reply: value used to check for request acknowledgment + * @timeout_base_ms: timeout for polling with preemption enabled + * + * Keep resending the @request to @mbox until PCODE acknowledges it, PCODE + * reports an error or an overall timeout of @timeout_base_ms+50 ms expires. + * The request is acknowledged once the PCODE reply dword equals @reply after + * applying @reply_mask. Polling is first attempted with preemption enabled + * for @timeout_base_ms and if this times out for another 50 ms with + * preemption disabled. + * + * Returns 0 on success, %-ETIMEDOUT in case of a timeout, <0 in case of some + * other error as reported by PCODE. + */ +int xe_pcode_request(struct xe_gt *gt, u32 mbox, u32 request, + u32 reply_mask, u32 reply, int timeout_base_ms) +{ + u32 status; + int ret; + + mutex_lock(>->pcode.lock); + + ret = xe_pcode_try_request(gt, mbox, request, reply_mask, reply, &status, + false, timeout_base_ms * 1000); + if (!ret) + goto out; + + /* + * The above can time out if the number of requests was low (2 in the + * worst case) _and_ PCODE was busy for some reason even after a + * (queued) request and @timeout_base_ms delay. As a workaround retry + * the poll with preemption disabled to maximize the number of + * requests. Increase the timeout from @timeout_base_ms to 50ms to + * account for interrupts that could reduce the number of these + * requests, and for any quirks of the PCODE firmware that delays + * the request completion. + */ + drm_err(>_to_xe(gt)->drm, + "PCODE timeout, retrying with preemption disabled\n"); + drm_WARN_ON_ONCE(>_to_xe(gt)->drm, timeout_base_ms > 1); + preempt_disable(); + ret = xe_pcode_try_request(gt, mbox, request, reply_mask, reply, &status, + true, timeout_base_ms * 1000); + preempt_enable(); + +out: + mutex_unlock(>->pcode.lock); + return status ? status : ret; +} +/** + * xe_pcode_init_min_freq_table - Initialize PCODE's QOS frequency table + * @gt: gt instance + * @min_gt_freq: Minimal (RPn) GT frequency in units of 50MHz. + * @max_gt_freq: Maximal (RP0) GT frequency in units of 50MHz. + * + * This function initialize PCODE's QOS frequency table for a proper minimal + * frequency/power steering decision, depending on the current requested GT + * frequency. For older platforms this was a more complete table including + * the IA freq. However for the latest platforms this table become a simple + * 1-1 Ring vs GT frequency. Even though, without setting it, PCODE might + * not take the right decisions for some memory frequencies and affect latency. + * + * It returns 0 on success, and -ERROR number on failure, -EINVAL if max + * frequency is higher then the minimal, and other errors directly translated + * from the PCODE Error returs: + * - -ENXIO: "Illegal Command" + * - -ETIMEDOUT: "Timed out" + * - -EINVAL: "Illegal Data" + * - -ENXIO, "Illegal Subcommand" + * - -EBUSY: "PCODE Locked" + * - -EOVERFLOW, "GT ratio out of range" + * - -EACCES, "PCODE Rejected" + * - -EPROTO, "Unknown" + */ +int xe_pcode_init_min_freq_table(struct xe_gt *gt, u32 min_gt_freq, + u32 max_gt_freq) +{ + int ret; + u32 freq; + + if (!gt_to_xe(gt)->info.has_llc) + return 0; + + if (max_gt_freq <= min_gt_freq) + return -EINVAL; + + mutex_lock(>->pcode.lock); + for (freq = min_gt_freq; freq <= max_gt_freq; freq++) { + u32 data = freq << PCODE_FREQ_RING_RATIO_SHIFT | freq; + + ret = pcode_mailbox_rw(gt, PCODE_WRITE_MIN_FREQ_TABLE, + &data, NULL, 1, false, false); + if (ret) + goto unlock; + } + +unlock: + mutex_unlock(>->pcode.lock); + return ret; +} + +/** + * xe_pcode_init - Ensure PCODE is initialized + * @gt: gt instance + * + * This function ensures that PCODE is properly initialized. To be called during + * probe and resume paths. + * + * It returns 0 on success, and -error number on failure. + */ +int xe_pcode_init(struct xe_gt *gt) +{ + u32 status, request = DGFX_GET_INIT_STATUS; + int timeout_us = 180000000; /* 3 min */ + int ret; + + if (gt_to_xe(gt)->info.skip_pcode) + return 0; + + if (!IS_DGFX(gt_to_xe(gt))) + return 0; + + mutex_lock(>->pcode.lock); + ret = xe_pcode_try_request(gt, DGFX_PCODE_STATUS, request, + DGFX_INIT_STATUS_COMPLETE, + DGFX_INIT_STATUS_COMPLETE, + &status, false, timeout_us); + mutex_unlock(>->pcode.lock); + + if (ret) + drm_err(>_to_xe(gt)->drm, + "PCODE initialization timedout after: 3 min\n"); + + return ret; +} + +/** + * xe_pcode_probe - Prepare xe_pcode and also ensure PCODE is initialized. + * @gt: gt instance + * + * This function initializes the xe_pcode component, and when needed, it ensures + * that PCODE has properly performed its initialization and it is really ready + * to go. To be called once only during probe. + * + * It returns 0 on success, and -error number on failure. + */ +int xe_pcode_probe(struct xe_gt *gt) +{ + drmm_mutex_init(>_to_xe(gt)->drm, >->pcode.lock); + + if (gt_to_xe(gt)->info.skip_pcode) + return 0; + + if (!IS_DGFX(gt_to_xe(gt))) + return 0; + + return xe_pcode_init(gt); +} |