From: Damien Lespiau Date: Thu, 21 May 2015 15:37:48 +0000 (+0100) Subject: drm/i915/skl: Deinit/init the display at suspend/resume X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=5d96d8afcfbb1500272756747e0bfcdbebf3b070;p=openwrt%2Fstaging%2Fblogic.git drm/i915/skl: Deinit/init the display at suspend/resume We need to re-init the display hardware when going out of suspend. This includes: - Hooking the PCH to the reset logic - Restoring CDCDLK - Enabling the DDB power Among those, only the CDCDLK one is a bit tricky. There's some complexity in that: - DPLL0 (which is the source for CDCLK) has two VCOs, each with a set of supported frequencies. As eDP also uses DPLL0 for its link rate, once DPLL0 is on, we restrict the possible eDP link rates the chosen VCO. - CDCLK also limits the bandwidth available to push pixels. So, as a first step, this commit restore what the BIOS set, until I can do more testing. In case that's of interest for the reviewer, I've unit tested the function that derives the decimal frequency field: #include #include #include #define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x))) static const struct dpll_freq { unsigned int freq; unsigned int decimal; } freqs[] = { { .freq = 308570, .decimal = 0b01001100111}, { .freq = 337500, .decimal = 0b01010100001}, { .freq = 432000, .decimal = 0b01101011110}, { .freq = 450000, .decimal = 0b01110000010}, { .freq = 540000, .decimal = 0b10000110110}, { .freq = 617140, .decimal = 0b10011010000}, { .freq = 675000, .decimal = 0b10101000100}, }; static void intbits(unsigned int v) { int i; for(i = 10; i >= 0; i--) putchar('0' + ((v >> i) & 1)); } static unsigned int freq_decimal(unsigned int freq /* in kHz */) { return (freq - 1000) / 500; } static void test_freq(const struct dpll_freq *entry) { unsigned int decimal = freq_decimal(entry->freq); printf("freq: %d, expected: ", entry->freq); intbits(entry->decimal); printf(", got: "); intbits(decimal); putchar('\n'); assert(decimal == entry->decimal); } int main(int argc, char **argv) { int i; for (i = 0; i < ARRAY_SIZE(freqs); i++) test_freq(&freqs[i]); return 0; } v2: - Rebase on top of -nightly - Use (freq - 1000) / 500 for the decimal frequency (Ville) - Fix setting the enable bit of HSW_NDE_RSTWRN_OPT (Ville) - Rename skl_display_{resume,suspend} to skl_{init,uninit}_cdclk to be consistent with the BXT code (Ville) - Store boot CDCLK in ddi_pll_init (Ville) - Merge dev_priv's skl_boot_cdclk into cdclk_freq - Use LCPLL_PLL_LOCK instead of (1 << 30) (Ville) - Replace various '0' by SKL_DPLL0 to be a bit more explicit that we're programming DPLL0 - Busy poll the PCU before doing the frequency change. It takes about 3/4 cycles, each separated by 10us, to get the ACK from the CPU (Ville) v3: - Restore dev_priv->skl_boot_cdclk, leaving unification with dev_priv->cdclk_freq for a later patch (Daniel, Ville) Reviewed-by: Ville Syrjälä Signed-off-by: Damien Lespiau Signed-off-by: Daniel Vetter --- diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index 93191c1fd18e..884b4f9b81c4 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -1047,6 +1047,8 @@ static int skl_suspend_complete(struct drm_i915_private *dev_priv) */ intel_csr_load_status_set(dev_priv, FW_UNINITIALIZED); + skl_uninit_cdclk(dev_priv); + return 0; } @@ -1093,6 +1095,7 @@ static int skl_resume_prepare(struct drm_i915_private *dev_priv) { struct drm_device *dev = dev_priv->dev; + skl_init_cdclk(dev_priv); intel_csr_load_program(dev); return 0; diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index b4eebd04565c..44d592f3b67c 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -1705,6 +1705,7 @@ struct drm_i915_private { int num_fence_regs; /* 8 on pre-965, 16 otherwise */ unsigned int fsb_freq, mem_freq, is_ddr3; + unsigned int skl_boot_cdclk; unsigned int cdclk_freq; unsigned int hpll_freq; diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index 3f94f38eec1f..c799b993c15d 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -6699,6 +6699,9 @@ enum skl_disp_power_wells { #define GEN9_MEM_LATENCY_LEVEL_1_5_SHIFT 8 #define GEN9_MEM_LATENCY_LEVEL_2_6_SHIFT 16 #define GEN9_MEM_LATENCY_LEVEL_3_7_SHIFT 24 +#define SKL_PCODE_CDCLK_CONTROL 0x7 +#define SKL_CDCLK_PREPARE_FOR_CHANGE 0x3 +#define SKL_CDCLK_READY_FOR_CHANGE 0x1 #define GEN6_PCODE_WRITE_MIN_FREQ_TABLE 0x8 #define GEN6_PCODE_READ_MIN_FREQ_TABLE 0x9 #define GEN6_READ_OC_PARAMS 0xc diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c index d602db25eb33..cacb07b7a8f1 100644 --- a/drivers/gpu/drm/i915/intel_ddi.c +++ b/drivers/gpu/drm/i915/intel_ddi.c @@ -2510,6 +2510,7 @@ void intel_ddi_pll_init(struct drm_device *dev) { struct drm_i915_private *dev_priv = dev->dev_private; uint32_t val = I915_READ(LCPLL_CTL); + int cdclk_freq; if (IS_SKYLAKE(dev)) skl_shared_dplls_init(dev_priv); @@ -2518,12 +2519,15 @@ void intel_ddi_pll_init(struct drm_device *dev) else hsw_shared_dplls_init(dev_priv); - DRM_DEBUG_KMS("CDCLK running at %dKHz\n", - dev_priv->display.get_display_clock_speed(dev)); + cdclk_freq = dev_priv->display.get_display_clock_speed(dev); + DRM_DEBUG_KMS("CDCLK running at %dKHz\n", cdclk_freq); if (IS_SKYLAKE(dev)) { + dev_priv->skl_boot_cdclk = cdclk_freq; if (!(I915_READ(LCPLL1_CTL) & LCPLL_PLL_ENABLE)) DRM_ERROR("LCPLL1 is disabled\n"); + else + intel_display_power_get(dev_priv, POWER_DOMAIN_PLLS); } else if (IS_BROXTON(dev)) { broxton_init_cdclk(dev); broxton_ddi_phy_init(dev); diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 048565572764..268043f65dd8 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -5527,6 +5527,214 @@ void broxton_uninit_cdclk(struct drm_device *dev) intel_display_power_put(dev_priv, POWER_DOMAIN_PLLS); } +static const struct skl_cdclk_entry { + unsigned int freq; + unsigned int vco; +} skl_cdclk_frequencies[] = { + { .freq = 308570, .vco = 8640 }, + { .freq = 337500, .vco = 8100 }, + { .freq = 432000, .vco = 8640 }, + { .freq = 450000, .vco = 8100 }, + { .freq = 540000, .vco = 8100 }, + { .freq = 617140, .vco = 8640 }, + { .freq = 675000, .vco = 8100 }, +}; + +static unsigned int skl_cdclk_decimal(unsigned int freq) +{ + return (freq - 1000) / 500; +} + +static unsigned int skl_cdclk_get_vco(unsigned int freq) +{ + unsigned int i; + + for (i = 0; i < ARRAY_SIZE(skl_cdclk_frequencies); i++) { + const struct skl_cdclk_entry *e = &skl_cdclk_frequencies[i]; + + if (e->freq == freq) + return e->vco; + } + + return 8100; +} + +static void +skl_dpll0_enable(struct drm_i915_private *dev_priv, unsigned int required_vco) +{ + unsigned int min_freq; + u32 val; + + /* select the minimum CDCLK before enabling DPLL 0 */ + val = I915_READ(CDCLK_CTL); + val &= ~CDCLK_FREQ_SEL_MASK | ~CDCLK_FREQ_DECIMAL_MASK; + val |= CDCLK_FREQ_337_308; + + if (required_vco == 8640) + min_freq = 308570; + else + min_freq = 337500; + + val = CDCLK_FREQ_337_308 | skl_cdclk_decimal(min_freq); + + I915_WRITE(CDCLK_CTL, val); + POSTING_READ(CDCLK_CTL); + + /* + * We always enable DPLL0 with the lowest link rate possible, but still + * taking into account the VCO required to operate the eDP panel at the + * desired frequency. The usual DP link rates operate with a VCO of + * 8100 while the eDP 1.4 alternate link rates need a VCO of 8640. + * The modeset code is responsible for the selection of the exact link + * rate later on, with the constraint of choosing a frequency that + * works with required_vco. + */ + val = I915_READ(DPLL_CTRL1); + + val &= ~(DPLL_CTRL1_HDMI_MODE(SKL_DPLL0) | DPLL_CTRL1_SSC(SKL_DPLL0) | + DPLL_CTRL1_LINK_RATE_MASK(SKL_DPLL0)); + val |= DPLL_CTRL1_OVERRIDE(SKL_DPLL0); + if (required_vco == 8640) + val |= DPLL_CTRL1_LINK_RATE(DPLL_CTRL1_LINK_RATE_1080, + SKL_DPLL0); + else + val |= DPLL_CTRL1_LINK_RATE(DPLL_CTRL1_LINK_RATE_810, + SKL_DPLL0); + + I915_WRITE(DPLL_CTRL1, val); + POSTING_READ(DPLL_CTRL1); + + I915_WRITE(LCPLL1_CTL, I915_READ(LCPLL1_CTL) | LCPLL_PLL_ENABLE); + + if (wait_for(I915_READ(LCPLL1_CTL) & LCPLL_PLL_LOCK, 5)) + DRM_ERROR("DPLL0 not locked\n"); +} + +static bool skl_cdclk_pcu_ready(struct drm_i915_private *dev_priv) +{ + int ret; + u32 val; + + /* inform PCU we want to change CDCLK */ + val = SKL_CDCLK_PREPARE_FOR_CHANGE; + mutex_lock(&dev_priv->rps.hw_lock); + ret = sandybridge_pcode_read(dev_priv, SKL_PCODE_CDCLK_CONTROL, &val); + mutex_unlock(&dev_priv->rps.hw_lock); + + return ret == 0 && (val & SKL_CDCLK_READY_FOR_CHANGE); +} + +static bool skl_cdclk_wait_for_pcu_ready(struct drm_i915_private *dev_priv) +{ + unsigned int i; + + for (i = 0; i < 15; i++) { + if (skl_cdclk_pcu_ready(dev_priv)) + return true; + udelay(10); + } + + return false; +} + +static void skl_set_cdclk(struct drm_i915_private *dev_priv, unsigned int freq) +{ + u32 freq_select, pcu_ack; + + DRM_DEBUG_DRIVER("Changing CDCLK to %dKHz\n", freq); + + if (!skl_cdclk_wait_for_pcu_ready(dev_priv)) { + DRM_ERROR("failed to inform PCU about cdclk change\n"); + return; + } + + /* set CDCLK_CTL */ + switch(freq) { + case 450000: + case 432000: + freq_select = CDCLK_FREQ_450_432; + pcu_ack = 1; + break; + case 540000: + freq_select = CDCLK_FREQ_540; + pcu_ack = 2; + break; + case 308570: + case 337500: + default: + freq_select = CDCLK_FREQ_337_308; + pcu_ack = 0; + break; + case 617140: + case 675000: + freq_select = CDCLK_FREQ_675_617; + pcu_ack = 3; + break; + } + + I915_WRITE(CDCLK_CTL, freq_select | skl_cdclk_decimal(freq)); + POSTING_READ(CDCLK_CTL); + + /* inform PCU of the change */ + mutex_lock(&dev_priv->rps.hw_lock); + sandybridge_pcode_write(dev_priv, SKL_PCODE_CDCLK_CONTROL, pcu_ack); + mutex_unlock(&dev_priv->rps.hw_lock); +} + +void skl_uninit_cdclk(struct drm_i915_private *dev_priv) +{ + /* disable DBUF power */ + I915_WRITE(DBUF_CTL, I915_READ(DBUF_CTL) & ~DBUF_POWER_REQUEST); + POSTING_READ(DBUF_CTL); + + udelay(10); + + if (I915_READ(DBUF_CTL) & DBUF_POWER_STATE) + DRM_ERROR("DBuf power disable timeout\n"); + + /* disable DPLL0 */ + I915_WRITE(LCPLL1_CTL, I915_READ(LCPLL1_CTL) & ~LCPLL_PLL_ENABLE); + if (wait_for(!(I915_READ(LCPLL1_CTL) & LCPLL_PLL_LOCK), 1)) + DRM_ERROR("Couldn't disable DPLL0\n"); + + intel_display_power_put(dev_priv, POWER_DOMAIN_PLLS); +} + +void skl_init_cdclk(struct drm_i915_private *dev_priv) +{ + u32 val; + unsigned int required_vco; + + /* enable PCH reset handshake */ + val = I915_READ(HSW_NDE_RSTWRN_OPT); + I915_WRITE(HSW_NDE_RSTWRN_OPT, val | RESET_PCH_HANDSHAKE_ENABLE); + + /* enable PG1 and Misc I/O */ + intel_display_power_get(dev_priv, POWER_DOMAIN_PLLS); + + /* DPLL0 already enabed !? */ + if (I915_READ(LCPLL1_CTL) & LCPLL_PLL_ENABLE) { + DRM_DEBUG_DRIVER("DPLL0 already running\n"); + return; + } + + /* enable DPLL0 */ + required_vco = skl_cdclk_get_vco(dev_priv->skl_boot_cdclk); + skl_dpll0_enable(dev_priv, required_vco); + + /* set CDCLK to the frequency the BIOS chose */ + skl_set_cdclk(dev_priv, dev_priv->skl_boot_cdclk); + + /* enable DBUF power */ + I915_WRITE(DBUF_CTL, I915_READ(DBUF_CTL) | DBUF_POWER_REQUEST); + POSTING_READ(DBUF_CTL); + + udelay(10); + + if (!(I915_READ(DBUF_CTL) & DBUF_POWER_STATE)) + DRM_ERROR("DBuf power enable timeout\n"); +} + /* returns HPLL frequency in kHz */ static int valleyview_get_vco(struct drm_i915_private *dev_priv) { diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index e94cb6e16456..02d83178bd03 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -1118,6 +1118,8 @@ void broxton_ddi_phy_init(struct drm_device *dev); void broxton_ddi_phy_uninit(struct drm_device *dev); void bxt_enable_dc9(struct drm_i915_private *dev_priv); void bxt_disable_dc9(struct drm_i915_private *dev_priv); +void skl_init_cdclk(struct drm_i915_private *dev_priv); +void skl_uninit_cdclk(struct drm_i915_private *dev_priv); void intel_dp_get_m_n(struct intel_crtc *crtc, struct intel_crtc_state *pipe_config); void intel_dp_set_m_n(struct intel_crtc *crtc, enum link_m_n_set m_n);