1 // SPDX-License-Identifier: MIT 2 /* 3 * Copyright © 2022 Intel Corporation 4 */ 5 6 #include "xe_pcode.h" 7 8 #include <linux/delay.h> 9 #include <linux/errno.h> 10 11 #include <drm/drm_managed.h> 12 13 #include "xe_gt.h" 14 #include "xe_mmio.h" 15 #include "xe_pcode_api.h" 16 17 /** 18 * DOC: PCODE 19 * 20 * Xe PCODE is the component responsible for interfacing with the PCODE 21 * firmware. 22 * It shall provide a very simple ABI to other Xe components, but be the 23 * single and consolidated place that will communicate with PCODE. All read 24 * and write operations to PCODE will be internal and private to this component. 25 * 26 * What's next: 27 * - PCODE hw metrics 28 * - PCODE for display operations 29 */ 30 31 static int pcode_mailbox_status(struct xe_gt *gt) 32 { 33 u32 err; 34 static const struct pcode_err_decode err_decode[] = { 35 [PCODE_ILLEGAL_CMD] = {-ENXIO, "Illegal Command"}, 36 [PCODE_TIMEOUT] = {-ETIMEDOUT, "Timed out"}, 37 [PCODE_ILLEGAL_DATA] = {-EINVAL, "Illegal Data"}, 38 [PCODE_ILLEGAL_SUBCOMMAND] = {-ENXIO, "Illegal Subcommand"}, 39 [PCODE_LOCKED] = {-EBUSY, "PCODE Locked"}, 40 [PCODE_GT_RATIO_OUT_OF_RANGE] = {-EOVERFLOW, 41 "GT ratio out of range"}, 42 [PCODE_REJECTED] = {-EACCES, "PCODE Rejected"}, 43 [PCODE_ERROR_MASK] = {-EPROTO, "Unknown"}, 44 }; 45 46 lockdep_assert_held(>->pcode.lock); 47 48 err = xe_mmio_read32(gt, PCODE_MAILBOX) & PCODE_ERROR_MASK; 49 if (err) { 50 drm_err(>_to_xe(gt)->drm, "PCODE Mailbox failed: %d %s", err, 51 err_decode[err].str ?: "Unknown"); 52 return err_decode[err].errno ?: -EPROTO; 53 } 54 55 return 0; 56 } 57 58 static int pcode_mailbox_rw(struct xe_gt *gt, u32 mbox, u32 *data0, u32 *data1, 59 unsigned int timeout_ms, bool return_data, 60 bool atomic) 61 { 62 int err; 63 64 lockdep_assert_held(>->pcode.lock); 65 66 if ((xe_mmio_read32(gt, PCODE_MAILBOX) & PCODE_READY) != 0) 67 return -EAGAIN; 68 69 xe_mmio_write32(gt, PCODE_DATA0, *data0); 70 xe_mmio_write32(gt, PCODE_DATA1, data1 ? *data1 : 0); 71 xe_mmio_write32(gt, PCODE_MAILBOX, PCODE_READY | mbox); 72 73 err = xe_mmio_wait32(gt, PCODE_MAILBOX, PCODE_READY, 0, 74 timeout_ms * 1000, NULL, atomic); 75 if (err) 76 return err; 77 78 if (return_data) { 79 *data0 = xe_mmio_read32(gt, PCODE_DATA0); 80 if (data1) 81 *data1 = xe_mmio_read32(gt, PCODE_DATA1); 82 } 83 84 return pcode_mailbox_status(gt); 85 } 86 87 int xe_pcode_write_timeout(struct xe_gt *gt, u32 mbox, u32 data, int timeout) 88 { 89 int err; 90 91 mutex_lock(>->pcode.lock); 92 err = pcode_mailbox_rw(gt, mbox, &data, NULL, timeout, false, false); 93 mutex_unlock(>->pcode.lock); 94 95 return err; 96 } 97 98 int xe_pcode_read(struct xe_gt *gt, u32 mbox, u32 *val, u32 *val1) 99 { 100 int err; 101 102 mutex_lock(>->pcode.lock); 103 err = pcode_mailbox_rw(gt, mbox, val, val1, 1, true, false); 104 mutex_unlock(>->pcode.lock); 105 106 return err; 107 } 108 109 static int xe_pcode_try_request(struct xe_gt *gt, u32 mbox, 110 u32 request, u32 reply_mask, u32 reply, 111 u32 *status, bool atomic, int timeout_us) 112 { 113 int slept, wait = 10; 114 115 for (slept = 0; slept < timeout_us; slept += wait) { 116 *status = pcode_mailbox_rw(gt, mbox, &request, NULL, 1, true, 117 atomic); 118 if ((*status == 0) && ((request & reply_mask) == reply)) 119 return 0; 120 121 if (atomic) 122 udelay(wait); 123 else 124 usleep_range(wait, wait << 1); 125 wait <<= 1; 126 } 127 128 return -ETIMEDOUT; 129 } 130 131 /** 132 * xe_pcode_request - send PCODE request until acknowledgment 133 * @gt: gt 134 * @mbox: PCODE mailbox ID the request is targeted for 135 * @request: request ID 136 * @reply_mask: mask used to check for request acknowledgment 137 * @reply: value used to check for request acknowledgment 138 * @timeout_base_ms: timeout for polling with preemption enabled 139 * 140 * Keep resending the @request to @mbox until PCODE acknowledges it, PCODE 141 * reports an error or an overall timeout of @timeout_base_ms+50 ms expires. 142 * The request is acknowledged once the PCODE reply dword equals @reply after 143 * applying @reply_mask. Polling is first attempted with preemption enabled 144 * for @timeout_base_ms and if this times out for another 50 ms with 145 * preemption disabled. 146 * 147 * Returns 0 on success, %-ETIMEDOUT in case of a timeout, <0 in case of some 148 * other error as reported by PCODE. 149 */ 150 int xe_pcode_request(struct xe_gt *gt, u32 mbox, u32 request, 151 u32 reply_mask, u32 reply, int timeout_base_ms) 152 { 153 u32 status; 154 int ret; 155 156 mutex_lock(>->pcode.lock); 157 158 ret = xe_pcode_try_request(gt, mbox, request, reply_mask, reply, &status, 159 false, timeout_base_ms * 1000); 160 if (!ret) 161 goto out; 162 163 /* 164 * The above can time out if the number of requests was low (2 in the 165 * worst case) _and_ PCODE was busy for some reason even after a 166 * (queued) request and @timeout_base_ms delay. As a workaround retry 167 * the poll with preemption disabled to maximize the number of 168 * requests. Increase the timeout from @timeout_base_ms to 50ms to 169 * account for interrupts that could reduce the number of these 170 * requests, and for any quirks of the PCODE firmware that delays 171 * the request completion. 172 */ 173 drm_err(>_to_xe(gt)->drm, 174 "PCODE timeout, retrying with preemption disabled\n"); 175 drm_WARN_ON_ONCE(>_to_xe(gt)->drm, timeout_base_ms > 1); 176 preempt_disable(); 177 ret = xe_pcode_try_request(gt, mbox, request, reply_mask, reply, &status, 178 true, timeout_base_ms * 1000); 179 preempt_enable(); 180 181 out: 182 mutex_unlock(>->pcode.lock); 183 return status ? status : ret; 184 } 185 /** 186 * xe_pcode_init_min_freq_table - Initialize PCODE's QOS frequency table 187 * @gt: gt instance 188 * @min_gt_freq: Minimal (RPn) GT frequency in units of 50MHz. 189 * @max_gt_freq: Maximal (RP0) GT frequency in units of 50MHz. 190 * 191 * This function initialize PCODE's QOS frequency table for a proper minimal 192 * frequency/power steering decision, depending on the current requested GT 193 * frequency. For older platforms this was a more complete table including 194 * the IA freq. However for the latest platforms this table become a simple 195 * 1-1 Ring vs GT frequency. Even though, without setting it, PCODE might 196 * not take the right decisions for some memory frequencies and affect latency. 197 * 198 * It returns 0 on success, and -ERROR number on failure, -EINVAL if max 199 * frequency is higher then the minimal, and other errors directly translated 200 * from the PCODE Error returs: 201 * - -ENXIO: "Illegal Command" 202 * - -ETIMEDOUT: "Timed out" 203 * - -EINVAL: "Illegal Data" 204 * - -ENXIO, "Illegal Subcommand" 205 * - -EBUSY: "PCODE Locked" 206 * - -EOVERFLOW, "GT ratio out of range" 207 * - -EACCES, "PCODE Rejected" 208 * - -EPROTO, "Unknown" 209 */ 210 int xe_pcode_init_min_freq_table(struct xe_gt *gt, u32 min_gt_freq, 211 u32 max_gt_freq) 212 { 213 int ret; 214 u32 freq; 215 216 if (!gt_to_xe(gt)->info.has_llc) 217 return 0; 218 219 if (max_gt_freq <= min_gt_freq) 220 return -EINVAL; 221 222 mutex_lock(>->pcode.lock); 223 for (freq = min_gt_freq; freq <= max_gt_freq; freq++) { 224 u32 data = freq << PCODE_FREQ_RING_RATIO_SHIFT | freq; 225 226 ret = pcode_mailbox_rw(gt, PCODE_WRITE_MIN_FREQ_TABLE, 227 &data, NULL, 1, false, false); 228 if (ret) 229 goto unlock; 230 } 231 232 unlock: 233 mutex_unlock(>->pcode.lock); 234 return ret; 235 } 236 237 /** 238 * xe_pcode_init - Ensure PCODE is initialized 239 * @gt: gt instance 240 * 241 * This function ensures that PCODE is properly initialized. To be called during 242 * probe and resume paths. 243 * 244 * It returns 0 on success, and -error number on failure. 245 */ 246 int xe_pcode_init(struct xe_gt *gt) 247 { 248 u32 status, request = DGFX_GET_INIT_STATUS; 249 int timeout_us = 180000000; /* 3 min */ 250 int ret; 251 252 if (!IS_DGFX(gt_to_xe(gt))) 253 return 0; 254 255 mutex_lock(>->pcode.lock); 256 ret = xe_pcode_try_request(gt, DGFX_PCODE_STATUS, request, 257 DGFX_INIT_STATUS_COMPLETE, 258 DGFX_INIT_STATUS_COMPLETE, 259 &status, false, timeout_us); 260 mutex_unlock(>->pcode.lock); 261 262 if (ret) 263 drm_err(>_to_xe(gt)->drm, 264 "PCODE initialization timedout after: 3 min\n"); 265 266 return ret; 267 } 268 269 /** 270 * xe_pcode_probe - Prepare xe_pcode and also ensure PCODE is initialized. 271 * @gt: gt instance 272 * 273 * This function initializes the xe_pcode component, and when needed, it ensures 274 * that PCODE has properly performed its initialization and it is really ready 275 * to go. To be called once only during probe. 276 * 277 * It returns 0 on success, and -error number on failure. 278 */ 279 int xe_pcode_probe(struct xe_gt *gt) 280 { 281 drmm_mutex_init(>_to_xe(gt)->drm, >->pcode.lock); 282 283 if (!IS_DGFX(gt_to_xe(gt))) 284 return 0; 285 286 return xe_pcode_init(gt); 287 } 288