diff options
Diffstat (limited to 'drivers/gpu/drm/i915/gt/intel_rc6.c')
-rw-r--r-- | drivers/gpu/drm/i915/gt/intel_rc6.c | 712 |
1 files changed, 712 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gt/intel_rc6.c b/drivers/gpu/drm/i915/gt/intel_rc6.c new file mode 100644 index 000000000000..70f0e01a38b9 --- /dev/null +++ b/drivers/gpu/drm/i915/gt/intel_rc6.c @@ -0,0 +1,712 @@ +/* + * SPDX-License-Identifier: MIT + * + * Copyright © 2019 Intel Corporation + */ + +#include <linux/pm_runtime.h> + +#include "i915_drv.h" +#include "intel_gt.h" +#include "intel_gt_pm.h" +#include "intel_rc6.h" +#include "intel_sideband.h" + +/** + * DOC: RC6 + * + * RC6 is a special power stage which allows the GPU to enter an very + * low-voltage mode when idle, using down to 0V while at this stage. This + * stage is entered automatically when the GPU is idle when RC6 support is + * enabled, and as soon as new workload arises GPU wakes up automatically as + * well. + * + * There are different RC6 modes available in Intel GPU, which differentiate + * among each other with the latency required to enter and leave RC6 and + * voltage consumed by the GPU in different states. + * + * The combination of the following flags define which states GPU is allowed + * to enter, while RC6 is the normal RC6 state, RC6p is the deep RC6, and + * RC6pp is deepest RC6. Their support by hardware varies according to the + * GPU, BIOS, chipset and platform. RC6 is usually the safest one and the one + * which brings the most power savings; deeper states save more power, but + * require higher latency to switch to and wake up. + */ + +static struct intel_gt *rc6_to_gt(struct intel_rc6 *rc6) +{ + return container_of(rc6, struct intel_gt, rc6); +} + +static struct intel_uncore *rc6_to_uncore(struct intel_rc6 *rc) +{ + return rc6_to_gt(rc)->uncore; +} + +static struct drm_i915_private *rc6_to_i915(struct intel_rc6 *rc) +{ + return rc6_to_gt(rc)->i915; +} + +static inline void set(struct intel_uncore *uncore, i915_reg_t reg, u32 val) +{ + intel_uncore_write_fw(uncore, reg, val); +} + +static void gen11_rc6_enable(struct intel_rc6 *rc6) +{ + struct intel_uncore *uncore = rc6_to_uncore(rc6); + struct intel_engine_cs *engine; + enum intel_engine_id id; + + /* 2b: Program RC6 thresholds.*/ + set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 54 << 16 | 85); + set(uncore, GEN10_MEDIA_WAKE_RATE_LIMIT, 150); + + set(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */ + set(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */ + for_each_engine(engine, rc6_to_gt(rc6), id) + set(uncore, RING_MAX_IDLE(engine->mmio_base), 10); + + set(uncore, GUC_MAX_IDLE_COUNT, 0xA); + + set(uncore, GEN6_RC_SLEEP, 0); + + set(uncore, GEN6_RC6_THRESHOLD, 50000); /* 50/125ms per EI */ + + /* + * 2c: Program Coarse Power Gating Policies. + * + * Bspec's guidance is to use 25us (really 25 * 1280ns) here. What we + * use instead is a more conservative estimate for the maximum time + * it takes us to service a CS interrupt and submit a new ELSP - that + * is the time which the GPU is idle waiting for the CPU to select the + * next request to execute. If the idle hysteresis is less than that + * interrupt service latency, the hardware will automatically gate + * the power well and we will then incur the wake up cost on top of + * the service latency. A similar guide from plane_state is that we + * do not want the enable hysteresis to less than the wakeup latency. + * + * igt/gem_exec_nop/sequential provides a rough estimate for the + * service latency, and puts it around 10us for Broadwell (and other + * big core) and around 40us for Broxton (and other low power cores). + * [Note that for legacy ringbuffer submission, this is less than 1us!] + * However, the wakeup latency on Broxton is closer to 100us. To be + * conservative, we have to factor in a context switch on top (due + * to ksoftirqd). + */ + set(uncore, GEN9_MEDIA_PG_IDLE_HYSTERESIS, 250); + set(uncore, GEN9_RENDER_PG_IDLE_HYSTERESIS, 250); + + /* 3a: Enable RC6 */ + set(uncore, GEN6_RC_CONTROL, + GEN6_RC_CTL_HW_ENABLE | + GEN6_RC_CTL_RC6_ENABLE | + GEN6_RC_CTL_EI_MODE(1)); + + set(uncore, GEN9_PG_ENABLE, + GEN9_RENDER_PG_ENABLE | + GEN9_MEDIA_PG_ENABLE | + GEN11_MEDIA_SAMPLER_PG_ENABLE); +} + +static void gen9_rc6_enable(struct intel_rc6 *rc6) +{ + struct intel_uncore *uncore = rc6_to_uncore(rc6); + struct intel_engine_cs *engine; + enum intel_engine_id id; + u32 rc6_mode; + + /* 2b: Program RC6 thresholds.*/ + if (INTEL_GEN(rc6_to_i915(rc6)) >= 10) { + set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 54 << 16 | 85); + set(uncore, GEN10_MEDIA_WAKE_RATE_LIMIT, 150); + } else if (IS_SKYLAKE(rc6_to_i915(rc6))) { + /* + * WaRsDoubleRc6WrlWithCoarsePowerGating:skl Doubling WRL only + * when CPG is enabled + */ + set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 108 << 16); + } else { + set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 54 << 16); + } + + set(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */ + set(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */ + for_each_engine(engine, rc6_to_gt(rc6), id) + set(uncore, RING_MAX_IDLE(engine->mmio_base), 10); + + set(uncore, GUC_MAX_IDLE_COUNT, 0xA); + + set(uncore, GEN6_RC_SLEEP, 0); + + /* + * 2c: Program Coarse Power Gating Policies. + * + * Bspec's guidance is to use 25us (really 25 * 1280ns) here. What we + * use instead is a more conservative estimate for the maximum time + * it takes us to service a CS interrupt and submit a new ELSP - that + * is the time which the GPU is idle waiting for the CPU to select the + * next request to execute. If the idle hysteresis is less than that + * interrupt service latency, the hardware will automatically gate + * the power well and we will then incur the wake up cost on top of + * the service latency. A similar guide from plane_state is that we + * do not want the enable hysteresis to less than the wakeup latency. + * + * igt/gem_exec_nop/sequential provides a rough estimate for the + * service latency, and puts it around 10us for Broadwell (and other + * big core) and around 40us for Broxton (and other low power cores). + * [Note that for legacy ringbuffer submission, this is less than 1us!] + * However, the wakeup latency on Broxton is closer to 100us. To be + * conservative, we have to factor in a context switch on top (due + * to ksoftirqd). + */ + set(uncore, GEN9_MEDIA_PG_IDLE_HYSTERESIS, 250); + set(uncore, GEN9_RENDER_PG_IDLE_HYSTERESIS, 250); + + /* 3a: Enable RC6 */ + set(uncore, GEN6_RC6_THRESHOLD, 37500); /* 37.5/125ms per EI */ + + /* WaRsUseTimeoutMode:cnl (pre-prod) */ + if (IS_CNL_REVID(rc6_to_i915(rc6), CNL_REVID_A0, CNL_REVID_C0)) + rc6_mode = GEN7_RC_CTL_TO_MODE; + else + rc6_mode = GEN6_RC_CTL_EI_MODE(1); + + set(uncore, GEN6_RC_CONTROL, + GEN6_RC_CTL_HW_ENABLE | + GEN6_RC_CTL_RC6_ENABLE | + rc6_mode); + + set(uncore, GEN9_PG_ENABLE, + GEN9_RENDER_PG_ENABLE | GEN9_MEDIA_PG_ENABLE); +} + +static void gen8_rc6_enable(struct intel_rc6 *rc6) +{ + struct intel_uncore *uncore = rc6_to_uncore(rc6); + struct intel_engine_cs *engine; + enum intel_engine_id id; + + /* 2b: Program RC6 thresholds.*/ + set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 40 << 16); + set(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */ + set(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */ + for_each_engine(engine, rc6_to_gt(rc6), id) + set(uncore, RING_MAX_IDLE(engine->mmio_base), 10); + set(uncore, GEN6_RC_SLEEP, 0); + set(uncore, GEN6_RC6_THRESHOLD, 625); /* 800us/1.28 for TO */ + + /* 3: Enable RC6 */ + set(uncore, GEN6_RC_CONTROL, + GEN6_RC_CTL_HW_ENABLE | + GEN7_RC_CTL_TO_MODE | + GEN6_RC_CTL_RC6_ENABLE); +} + +static void gen6_rc6_enable(struct intel_rc6 *rc6) +{ + struct intel_uncore *uncore = rc6_to_uncore(rc6); + struct drm_i915_private *i915 = rc6_to_i915(rc6); + struct intel_engine_cs *engine; + enum intel_engine_id id; + u32 rc6vids, rc6_mask; + int ret; + + set(uncore, GEN6_RC1_WAKE_RATE_LIMIT, 1000 << 16); + set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 40 << 16 | 30); + set(uncore, GEN6_RC6pp_WAKE_RATE_LIMIT, 30); + set(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); + set(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); + + for_each_engine(engine, rc6_to_gt(rc6), id) + set(uncore, RING_MAX_IDLE(engine->mmio_base), 10); + + set(uncore, GEN6_RC_SLEEP, 0); + set(uncore, GEN6_RC1e_THRESHOLD, 1000); + if (IS_IVYBRIDGE(i915)) + set(uncore, GEN6_RC6_THRESHOLD, 125000); + else + set(uncore, GEN6_RC6_THRESHOLD, 50000); + set(uncore, GEN6_RC6p_THRESHOLD, 150000); + set(uncore, GEN6_RC6pp_THRESHOLD, 64000); /* unused */ + + /* We don't use those on Haswell */ + rc6_mask = GEN6_RC_CTL_RC6_ENABLE; + if (HAS_RC6p(i915)) + rc6_mask |= GEN6_RC_CTL_RC6p_ENABLE; + if (HAS_RC6pp(i915)) + rc6_mask |= GEN6_RC_CTL_RC6pp_ENABLE; + set(uncore, GEN6_RC_CONTROL, + rc6_mask | + GEN6_RC_CTL_EI_MODE(1) | + GEN6_RC_CTL_HW_ENABLE); + + rc6vids = 0; + ret = sandybridge_pcode_read(i915, GEN6_PCODE_READ_RC6VIDS, + &rc6vids, NULL); + if (IS_GEN(i915, 6) && ret) { + DRM_DEBUG_DRIVER("Couldn't check for BIOS workaround\n"); + } else if (IS_GEN(i915, 6) && + (GEN6_DECODE_RC6_VID(rc6vids & 0xff) < 450)) { + DRM_DEBUG_DRIVER("You should update your BIOS. Correcting minimum rc6 voltage (%dmV->%dmV)\n", + GEN6_DECODE_RC6_VID(rc6vids & 0xff), 450); + rc6vids &= 0xffff00; + rc6vids |= GEN6_ENCODE_RC6_VID(450); + ret = sandybridge_pcode_write(i915, GEN6_PCODE_WRITE_RC6VIDS, rc6vids); + if (ret) + DRM_ERROR("Couldn't fix incorrect rc6 voltage\n"); + } +} + +/* Check that the pcbr address is not empty. */ +static int chv_rc6_init(struct intel_rc6 *rc6) +{ + struct intel_uncore *uncore = rc6_to_uncore(rc6); + resource_size_t pctx_paddr, paddr; + resource_size_t pctx_size = 32 * SZ_1K; + u32 pcbr; + + pcbr = intel_uncore_read(uncore, VLV_PCBR); + if ((pcbr >> VLV_PCBR_ADDR_SHIFT) == 0) { + DRM_DEBUG_DRIVER("BIOS didn't set up PCBR, fixing up\n"); + paddr = rc6_to_i915(rc6)->dsm.end + 1 - pctx_size; + GEM_BUG_ON(paddr > U32_MAX); + + pctx_paddr = (paddr & ~4095); + intel_uncore_write(uncore, VLV_PCBR, pctx_paddr); + } + + return 0; +} + +static int vlv_rc6_init(struct intel_rc6 *rc6) +{ + struct drm_i915_private *i915 = rc6_to_i915(rc6); + struct intel_uncore *uncore = rc6_to_uncore(rc6); + struct drm_i915_gem_object *pctx; + resource_size_t pctx_paddr; + resource_size_t pctx_size = 24 * SZ_1K; + u32 pcbr; + + pcbr = intel_uncore_read(uncore, VLV_PCBR); + if (pcbr) { + /* BIOS set it up already, grab the pre-alloc'd space */ + resource_size_t pcbr_offset; + + pcbr_offset = (pcbr & ~4095) - i915->dsm.start; + pctx = i915_gem_object_create_stolen_for_preallocated(i915, + pcbr_offset, + I915_GTT_OFFSET_NONE, + pctx_size); + if (IS_ERR(pctx)) + return PTR_ERR(pctx); + + goto out; + } + + DRM_DEBUG_DRIVER("BIOS didn't set up PCBR, fixing up\n"); + + /* + * From the Gunit register HAS: + * The Gfx driver is expected to program this register and ensure + * proper allocation within Gfx stolen memory. For example, this + * register should be programmed such than the PCBR range does not + * overlap with other ranges, such as the frame buffer, protected + * memory, or any other relevant ranges. + */ + pctx = i915_gem_object_create_stolen(i915, pctx_size); + if (IS_ERR(pctx)) { + DRM_DEBUG("not enough stolen space for PCTX, disabling\n"); + return PTR_ERR(pctx); + } + + GEM_BUG_ON(range_overflows_t(u64, + i915->dsm.start, + pctx->stolen->start, + U32_MAX)); + pctx_paddr = i915->dsm.start + pctx->stolen->start; + intel_uncore_write(uncore, VLV_PCBR, pctx_paddr); + +out: + rc6->pctx = pctx; + return 0; +} + +static void chv_rc6_enable(struct intel_rc6 *rc6) +{ + struct intel_uncore *uncore = rc6_to_uncore(rc6); + struct intel_engine_cs *engine; + enum intel_engine_id id; + + /* 2a: Program RC6 thresholds.*/ + set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 40 << 16); + set(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */ + set(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */ + + for_each_engine(engine, rc6_to_gt(rc6), id) + set(uncore, RING_MAX_IDLE(engine->mmio_base), 10); + set(uncore, GEN6_RC_SLEEP, 0); + + /* TO threshold set to 500 us (0x186 * 1.28 us) */ + set(uncore, GEN6_RC6_THRESHOLD, 0x186); + + /* Allows RC6 residency counter to work */ + set(uncore, VLV_COUNTER_CONTROL, + _MASKED_BIT_ENABLE(VLV_COUNT_RANGE_HIGH | + VLV_MEDIA_RC6_COUNT_EN | + VLV_RENDER_RC6_COUNT_EN)); + + /* 3: Enable RC6 */ + set(uncore, GEN6_RC_CONTROL, GEN7_RC_CTL_TO_MODE); +} + +static void vlv_rc6_enable(struct intel_rc6 *rc6) +{ + struct intel_uncore *uncore = rc6_to_uncore(rc6); + struct intel_engine_cs *engine; + enum intel_engine_id id; + + set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 0x00280000); + set(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); + set(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); + + for_each_engine(engine, rc6_to_gt(rc6), id) + set(uncore, RING_MAX_IDLE(engine->mmio_base), 10); + + set(uncore, GEN6_RC6_THRESHOLD, 0x557); + + /* Allows RC6 residency counter to work */ + set(uncore, VLV_COUNTER_CONTROL, + _MASKED_BIT_ENABLE(VLV_COUNT_RANGE_HIGH | + VLV_MEDIA_RC0_COUNT_EN | + VLV_RENDER_RC0_COUNT_EN | + VLV_MEDIA_RC6_COUNT_EN | + VLV_RENDER_RC6_COUNT_EN)); + + set(uncore, GEN6_RC_CONTROL, + GEN7_RC_CTL_TO_MODE | VLV_RC_CTL_CTX_RST_PARALLEL); +} + +static bool bxt_check_bios_rc6_setup(struct intel_rc6 *rc6) +{ + struct intel_uncore *uncore = rc6_to_uncore(rc6); + struct drm_i915_private *i915 = rc6_to_i915(rc6); + u32 rc6_ctx_base, rc_ctl, rc_sw_target; + bool enable_rc6 = true; + + rc_ctl = intel_uncore_read(uncore, GEN6_RC_CONTROL); + rc_sw_target = intel_uncore_read(uncore, GEN6_RC_STATE); + rc_sw_target &= RC_SW_TARGET_STATE_MASK; + rc_sw_target >>= RC_SW_TARGET_STATE_SHIFT; + DRM_DEBUG_DRIVER("BIOS enabled RC states: " + "HW_CTRL %s HW_RC6 %s SW_TARGET_STATE %x\n", + onoff(rc_ctl & GEN6_RC_CTL_HW_ENABLE), + onoff(rc_ctl & GEN6_RC_CTL_RC6_ENABLE), + rc_sw_target); + + if (!(intel_uncore_read(uncore, RC6_LOCATION) & RC6_CTX_IN_DRAM)) { + DRM_DEBUG_DRIVER("RC6 Base location not set properly.\n"); + enable_rc6 = false; + } + + /* + * The exact context size is not known for BXT, so assume a page size + * for this check. + */ + rc6_ctx_base = + intel_uncore_read(uncore, RC6_CTX_BASE) & RC6_CTX_BASE_MASK; + if (!(rc6_ctx_base >= i915->dsm_reserved.start && + rc6_ctx_base + PAGE_SIZE < i915->dsm_reserved.end)) { + DRM_DEBUG_DRIVER("RC6 Base address not as expected.\n"); + enable_rc6 = false; + } + + if (!((intel_uncore_read(uncore, PWRCTX_MAXCNT_RCSUNIT) & IDLE_TIME_MASK) > 1 && + (intel_uncore_read(uncore, PWRCTX_MAXCNT_VCSUNIT0) & IDLE_TIME_MASK) > 1 && + (intel_uncore_read(uncore, PWRCTX_MAXCNT_BCSUNIT) & IDLE_TIME_MASK) > 1 && + (intel_uncore_read(uncore, PWRCTX_MAXCNT_VECSUNIT) & IDLE_TIME_MASK) > 1)) { + DRM_DEBUG_DRIVER("Engine Idle wait time not set properly.\n"); + enable_rc6 = false; + } + + if (!intel_uncore_read(uncore, GEN8_PUSHBUS_CONTROL) || + !intel_uncore_read(uncore, GEN8_PUSHBUS_ENABLE) || + !intel_uncore_read(uncore, GEN8_PUSHBUS_SHIFT)) { + DRM_DEBUG_DRIVER("Pushbus not setup properly.\n"); + enable_rc6 = false; + } + + if (!intel_uncore_read(uncore, GEN6_GFXPAUSE)) { + DRM_DEBUG_DRIVER("GFX pause not setup properly.\n"); + enable_rc6 = false; + } + + if (!intel_uncore_read(uncore, GEN8_MISC_CTRL0)) { + DRM_DEBUG_DRIVER("GPM control not setup properly.\n"); + enable_rc6 = false; + } + + return enable_rc6; +} + +static bool rc6_supported(struct intel_rc6 *rc6) +{ + struct drm_i915_private *i915 = rc6_to_i915(rc6); + + if (!HAS_RC6(i915)) + return false; + + if (intel_vgpu_active(i915)) + return false; + + if (is_mock_gt(rc6_to_gt(rc6))) + return false; + + if (IS_GEN9_LP(i915) && !bxt_check_bios_rc6_setup(rc6)) { + dev_notice(i915->drm.dev, + "RC6 and powersaving disabled by BIOS\n"); + return false; + } + + return true; +} + +static void rpm_get(struct intel_rc6 *rc6) +{ + GEM_BUG_ON(rc6->wakeref); + pm_runtime_get_sync(&rc6_to_i915(rc6)->drm.pdev->dev); + rc6->wakeref = true; +} + +static void rpm_put(struct intel_rc6 *rc6) +{ + GEM_BUG_ON(!rc6->wakeref); + pm_runtime_put(&rc6_to_i915(rc6)->drm.pdev->dev); + rc6->wakeref = false; +} + +static void __intel_rc6_disable(struct intel_rc6 *rc6) +{ + struct drm_i915_private *i915 = rc6_to_i915(rc6); + struct intel_uncore *uncore = rc6_to_uncore(rc6); + + intel_uncore_forcewake_get(uncore, FORCEWAKE_ALL); + if (INTEL_GEN(i915) >= 9) + set(uncore, GEN9_PG_ENABLE, 0); + set(uncore, GEN6_RC_CONTROL, 0); + set(uncore, GEN6_RC_STATE, 0); + intel_uncore_forcewake_put(uncore, FORCEWAKE_ALL); +} + +void intel_rc6_init(struct intel_rc6 *rc6) +{ + struct drm_i915_private *i915 = rc6_to_i915(rc6); + int err; + + /* Disable runtime-pm until we can save the GPU state with rc6 pctx */ + rpm_get(rc6); + + if (!rc6_supported(rc6)) + return; + + if (IS_CHERRYVIEW(i915)) + err = chv_rc6_init(rc6); + else if (IS_VALLEYVIEW(i915)) + err = vlv_rc6_init(rc6); + else + err = 0; + + /* Sanitize rc6, ensure it is disabled before we are ready. */ + __intel_rc6_disable(rc6); + + rc6->supported = err == 0; +} + +void intel_rc6_sanitize(struct intel_rc6 *rc6) +{ + if (rc6->supported) + __intel_rc6_disable(rc6); +} + +void intel_rc6_enable(struct intel_rc6 *rc6) +{ + struct drm_i915_private *i915 = rc6_to_i915(rc6); + struct intel_uncore *uncore = rc6_to_uncore(rc6); + + if (!rc6->supported) + return; + + GEM_BUG_ON(rc6->enabled); + + intel_uncore_forcewake_get(uncore, FORCEWAKE_ALL); + + if (IS_CHERRYVIEW(i915)) + chv_rc6_enable(rc6); + else if (IS_VALLEYVIEW(i915)) + vlv_rc6_enable(rc6); + else if (INTEL_GEN(i915) >= 11) + gen11_rc6_enable(rc6); + else if (INTEL_GEN(i915) >= 9) + gen9_rc6_enable(rc6); + else if (IS_BROADWELL(i915)) + gen8_rc6_enable(rc6); + else if (INTEL_GEN(i915) >= 6) + gen6_rc6_enable(rc6); + + intel_uncore_forcewake_put(uncore, FORCEWAKE_ALL); + + /* rc6 is ready, runtime-pm is go! */ + rpm_put(rc6); + rc6->enabled = true; +} + +void intel_rc6_disable(struct intel_rc6 *rc6) +{ + if (!rc6->enabled) + return; + + rpm_get(rc6); + rc6->enabled = false; + + __intel_rc6_disable(rc6); +} + +void intel_rc6_fini(struct intel_rc6 *rc6) +{ + struct drm_i915_gem_object *pctx; + + intel_rc6_disable(rc6); + + pctx = fetch_and_zero(&rc6->pctx); + if (pctx) + i915_gem_object_put(pctx); + + if (rc6->wakeref) + rpm_put(rc6); +} + +static u64 vlv_residency_raw(struct intel_uncore *uncore, const i915_reg_t reg) +{ + u32 lower, upper, tmp; + int loop = 2; + + /* + * The register accessed do not need forcewake. We borrow + * uncore lock to prevent concurrent access to range reg. + */ + lockdep_assert_held(&uncore->lock); + + /* + * vlv and chv residency counters are 40 bits in width. + * With a control bit, we can choose between upper or lower + * 32bit window into this counter. + * + * Although we always use the counter in high-range mode elsewhere, + * userspace may attempt to read the value before rc6 is initialised, + * before we have set the default VLV_COUNTER_CONTROL value. So always + * set the high bit to be safe. + */ + set(uncore, VLV_COUNTER_CONTROL, + _MASKED_BIT_ENABLE(VLV_COUNT_RANGE_HIGH)); + upper = intel_uncore_read_fw(uncore, reg); + do { + tmp = upper; + + set(uncore, VLV_COUNTER_CONTROL, + _MASKED_BIT_DISABLE(VLV_COUNT_RANGE_HIGH)); + lower = intel_uncore_read_fw(uncore, reg); + + set(uncore, VLV_COUNTER_CONTROL, + _MASKED_BIT_ENABLE(VLV_COUNT_RANGE_HIGH)); + upper = intel_uncore_read_fw(uncore, reg); + } while (upper != tmp && --loop); + + /* + * Everywhere else we always use VLV_COUNTER_CONTROL with the + * VLV_COUNT_RANGE_HIGH bit set - so it is safe to leave it set + * now. + */ + + return lower | (u64)upper << 8; +} + +u64 intel_rc6_residency_ns(struct intel_rc6 *rc6, const i915_reg_t reg) +{ + struct drm_i915_private *i915 = rc6_to_i915(rc6); + struct intel_uncore *uncore = rc6_to_uncore(rc6); + u64 time_hw, prev_hw, overflow_hw; + unsigned int fw_domains; + unsigned long flags; + unsigned int i; + u32 mul, div; + + if (!rc6->supported) + return 0; + + /* + * Store previous hw counter values for counter wrap-around handling. + * + * There are only four interesting registers and they live next to each + * other so we can use the relative address, compared to the smallest + * one as the index into driver storage. + */ + i = (i915_mmio_reg_offset(reg) - + i915_mmio_reg_offset(GEN6_GT_GFX_RC6_LOCKED)) / sizeof(u32); + if (WARN_ON_ONCE(i >= ARRAY_SIZE(rc6->cur_residency))) + return 0; + + fw_domains = intel_uncore_forcewake_for_reg(uncore, reg, FW_REG_READ); + + spin_lock_irqsave(&uncore->lock, flags); + intel_uncore_forcewake_get__locked(uncore, fw_domains); + + /* On VLV and CHV, residency time is in CZ units rather than 1.28us */ + if (IS_VALLEYVIEW(i915) || IS_CHERRYVIEW(i915)) { + mul = 1000000; + div = i915->czclk_freq; + overflow_hw = BIT_ULL(40); + time_hw = vlv_residency_raw(uncore, reg); + } else { + /* 833.33ns units on Gen9LP, 1.28us elsewhere. */ + if (IS_GEN9_LP(i915)) { + mul = 10000; + div = 12; + } else { + mul = 1280; + div = 1; + } + + overflow_hw = BIT_ULL(32); + time_hw = intel_uncore_read_fw(uncore, reg); + } + + /* + * Counter wrap handling. + * + * But relying on a sufficient frequency of queries otherwise counters + * can still wrap. + */ + prev_hw = rc6->prev_hw_residency[i]; + rc6->prev_hw_residency[i] = time_hw; + + /* RC6 delta from last sample. */ + if (time_hw >= prev_hw) + time_hw -= prev_hw; + else + time_hw += overflow_hw - prev_hw; + + /* Add delta to RC6 extended raw driver copy. */ + time_hw += rc6->cur_residency[i]; + rc6->cur_residency[i] = time_hw; + + intel_uncore_forcewake_put__locked(uncore, fw_domains); + spin_unlock_irqrestore(&uncore->lock, flags); + + return mul_u64_u32_div(time_hw, mul, div); +} + +u64 intel_rc6_residency_us(struct intel_rc6 *rc6, i915_reg_t reg) +{ + return DIV_ROUND_UP_ULL(intel_rc6_residency_ns(rc6, reg), 1000); +} |