[Intel-gfx] [PATCH 3/4] drm/i915: add functions to disable and restore LCPLL
Daniel Vetter
daniel at ffwll.ch
Tue Jul 23 16:49:32 CEST 2013
On Tue, Jul 23, 2013 at 11:19:26AM -0300, Paulo Zanoni wrote:
> From: Paulo Zanoni <paulo.r.zanoni at intel.com>
>
> For now there are no callers, but these functions are going to be
> needed for the code that allows Package C8+. Other future features may
> also require this code.
>
> Also merge the commit which introduced assert_can_disable_lcpll and
> had the following commit message:
>
> Most of the hardware needs to be disabled before LCPLL is disabled, so
> let's add a function to assert some of items listed in the "Display
> Sequences for LCPLL disabling" documentation.
>
> The idea is that hsw_disable_lcpll should not disable the hardware,
> the callers need to take care of calling hsw_disable_lcpll only once
> everything is already disabled.
>
> v2: - Rebase.
> - Fix D_COMP wait timeout.
> v3: - Use wait_for_atomic_use (Ben)
> - Remove/add a useless/needed POSTING_READ (Ben)
> - Early return in case LCPLL is already restored (Ben)
> - Add ndelay(100) (Ben)
> v4: - Merge the commit that added assert_can_disable_lcpll (Ben)
> - Add interrupt assertions (Ben)
>
> Reviewed-by: Ben Widawsky <ben at bwidawsk.net>
> Signed-off-by: Paulo Zanoni <paulo.r.zanoni at intel.com>
> ---
> drivers/gpu/drm/i915/i915_reg.h | 15 ++++
> drivers/gpu/drm/i915/intel_display.c | 136 +++++++++++++++++++++++++++++++++++
> drivers/gpu/drm/i915/intel_drv.h | 3 +
> 3 files changed, 154 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index 0dfcbad..6caa748 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -2261,6 +2261,8 @@
> #define BLC_PWM_CPU_CTL2 0x48250
> #define BLC_PWM_CPU_CTL 0x48254
>
> +#define HSW_BLC_PWM2_CTL 0x48350
> +
> /* PCH CTL1 is totally different, all but the below bits are reserved. CTL2 is
> * like the normal CTL from gen4 and earlier. Hooray for confusing naming. */
> #define BLC_PWM_PCH_CTL1 0xc8250
> @@ -2269,6 +2271,12 @@
> #define BLM_PCH_POLARITY (1 << 29)
> #define BLC_PWM_PCH_CTL2 0xc8254
>
> +#define UTIL_PIN_CTL 0x48400
> +#define UTIL_PIN_ENABLE (1 << 31)
> +
> +#define PCH_GTC_CTL 0xe7000
> +#define PCH_GTC_ENABLE (1 << 31)
> +
> /* TV port control */
> #define TV_CTL 0x68000
> /** Enables the TV encoder */
> @@ -5009,7 +5017,14 @@
> #define LCPLL_CLK_FREQ_450 (0<<26)
> #define LCPLL_CD_CLOCK_DISABLE (1<<25)
> #define LCPLL_CD2X_CLOCK_DISABLE (1<<23)
> +#define LCPLL_POWER_DOWN_ALLOW (1<<22)
> #define LCPLL_CD_SOURCE_FCLK (1<<21)
> +#define LCPLL_CD_SOURCE_FCLK_DONE (1<<19)
> +
> +#define D_COMP (MCHBAR_MIRROR_BASE_SNB + 0x5F0C)
> +#define D_COMP_RCOMP_IN_PROGRESS (1<<9)
> +#define D_COMP_COMP_FORCE (1<<8)
> +#define D_COMP_COMP_DISABLE (1<<0)
>
> /* Pipe WM_LINETIME - watermark line time */
> #define PIPE_WM_LINETIME_A 0x45270
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index deee650d..0b0696a 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -5922,6 +5922,142 @@ static bool ironlake_get_pipe_config(struct intel_crtc *crtc,
> return true;
> }
>
> +static void assert_can_disable_lcpll(struct drm_i915_private *dev_priv)
> +{
> + struct drm_device *dev = dev_priv->dev;
> + struct intel_ddi_plls *plls = &dev_priv->ddi_plls;
> + struct intel_crtc *crtc;
> + unsigned long irqflags;
> + uint32_t val, pch_hpd_mask;
> +
> + pch_hpd_mask = SDE_PORTB_HOTPLUG_CPT | SDE_PORTC_HOTPLUG_CPT;
> + if (!HAS_LP_PCH(dev_priv))
This didn't compile, I've fixed it up.
-Daniel
> + pch_hpd_mask |= SDE_PORTD_HOTPLUG_CPT | SDE_CRT_HOTPLUG_CPT;
> +
> + list_for_each_entry(crtc, &dev->mode_config.crtc_list, base.head)
> + WARN(crtc->base.enabled, "CRTC for pipe %c enabled\n",
> + pipe_name(crtc->pipe));
> +
> + WARN(I915_READ(HSW_PWR_WELL_DRIVER), "Power well on\n");
> + WARN(plls->spll_refcount, "SPLL enabled\n");
> + WARN(plls->wrpll1_refcount, "WRPLL1 enabled\n");
> + WARN(plls->wrpll2_refcount, "WRPLL2 enabled\n");
> + WARN(I915_READ(PCH_PP_STATUS) & PP_ON, "Panel power on\n");
> + WARN(I915_READ(BLC_PWM_CPU_CTL2) & BLM_PWM_ENABLE,
> + "CPU PWM1 enabled\n");
> + WARN(I915_READ(HSW_BLC_PWM2_CTL) & BLM_PWM_ENABLE,
> + "CPU PWM2 enabled\n");
> + WARN(I915_READ(BLC_PWM_PCH_CTL1) & BLM_PCH_PWM_ENABLE,
> + "PCH PWM1 enabled\n");
> + WARN(I915_READ(UTIL_PIN_CTL) & UTIL_PIN_ENABLE,
> + "Utility pin enabled\n");
> + WARN(I915_READ(PCH_GTC_CTL) & PCH_GTC_ENABLE, "PCH GTC enabled\n");
> +
> + spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
> + val = I915_READ(DEIMR);
> + WARN((val & ~DE_PCH_EVENT_IVB) != val,
> + "Unexpected DEIMR bits enabled: 0x%x\n", val);
> + val = I915_READ(SDEIMR);
> + WARN((val & ~pch_hpd_mask) != val,
> + "Unexpected SDEIMR bits enabled: 0x%x\n", val);
> + spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags);
> +}
> +
> +/*
> + * This function implements pieces of two sequences from BSpec:
> + * - Sequence for display software to disable LCPLL
> + * - Sequence for display software to allow package C8+
> + * The steps implemented here are just the steps that actually touch the LCPLL
> + * register. Callers should take care of disabling all the display engine
> + * functions, doing the mode unset, fixing interrupts, etc.
> + */
> +void hsw_disable_lcpll(struct drm_i915_private *dev_priv,
> + bool switch_to_fclk, bool allow_power_down)
> +{
> + uint32_t val;
> +
> + assert_can_disable_lcpll(dev_priv);
> +
> + val = I915_READ(LCPLL_CTL);
> +
> + if (switch_to_fclk) {
> + val |= LCPLL_CD_SOURCE_FCLK;
> + I915_WRITE(LCPLL_CTL, val);
> +
> + if (wait_for_atomic_us(I915_READ(LCPLL_CTL) &
> + LCPLL_CD_SOURCE_FCLK_DONE, 1))
> + DRM_ERROR("Switching to FCLK failed\n");
> +
> + val = I915_READ(LCPLL_CTL);
> + }
> +
> + val |= LCPLL_PLL_DISABLE;
> + I915_WRITE(LCPLL_CTL, val);
> + POSTING_READ(LCPLL_CTL);
> +
> + if (wait_for((I915_READ(LCPLL_CTL) & LCPLL_PLL_LOCK) == 0, 1))
> + DRM_ERROR("LCPLL still locked\n");
> +
> + val = I915_READ(D_COMP);
> + val |= D_COMP_COMP_DISABLE;
> + I915_WRITE(D_COMP, val);
> + POSTING_READ(D_COMP);
> + ndelay(100);
> +
> + if (wait_for((I915_READ(D_COMP) & D_COMP_RCOMP_IN_PROGRESS) == 0, 1))
> + DRM_ERROR("D_COMP RCOMP still in progress\n");
> +
> + if (allow_power_down) {
> + val = I915_READ(LCPLL_CTL);
> + val |= LCPLL_POWER_DOWN_ALLOW;
> + I915_WRITE(LCPLL_CTL, val);
> + POSTING_READ(LCPLL_CTL);
> + }
> +}
> +
> +/*
> + * Fully restores LCPLL, disallowing power down and switching back to LCPLL
> + * source.
> + */
> +void hsw_restore_lcpll(struct drm_i915_private *dev_priv)
> +{
> + uint32_t val;
> +
> + val = I915_READ(LCPLL_CTL);
> +
> + if ((val & (LCPLL_PLL_LOCK | LCPLL_PLL_DISABLE | LCPLL_CD_SOURCE_FCLK |
> + LCPLL_POWER_DOWN_ALLOW)) == LCPLL_PLL_LOCK)
> + return;
> +
> + if (val & LCPLL_POWER_DOWN_ALLOW) {
> + val &= ~LCPLL_POWER_DOWN_ALLOW;
> + I915_WRITE(LCPLL_CTL, val);
> + }
> +
> + val = I915_READ(D_COMP);
> + val |= D_COMP_COMP_FORCE;
> + val &= ~D_COMP_COMP_DISABLE;
> + I915_WRITE(D_COMP, val);
> + I915_READ(D_COMP);
> +
> + val = I915_READ(LCPLL_CTL);
> + val &= ~LCPLL_PLL_DISABLE;
> + I915_WRITE(LCPLL_CTL, val);
> +
> + if (wait_for(I915_READ(LCPLL_CTL) & LCPLL_PLL_LOCK, 5))
> + DRM_ERROR("LCPLL not locked yet\n");
> +
> + if (val & LCPLL_CD_SOURCE_FCLK) {
> + val = I915_READ(LCPLL_CTL);
> + val &= ~LCPLL_CD_SOURCE_FCLK;
> + I915_WRITE(LCPLL_CTL, val);
> +
> + if (wait_for_atomic_us((I915_READ(LCPLL_CTL) &
> + LCPLL_CD_SOURCE_FCLK_DONE) == 0, 1))
> + DRM_ERROR("Switching back to LCPLL failed\n");
> + }
> +}
> +
> static void haswell_modeset_global_resources(struct drm_device *dev)
> {
> bool enable = false;
> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
> index 31087ff..3fbe80b 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -838,5 +838,8 @@ extern bool intel_set_pch_fifo_underrun_reporting(struct drm_device *dev,
> extern void intel_edp_psr_enable(struct intel_dp *intel_dp);
> extern void intel_edp_psr_disable(struct intel_dp *intel_dp);
> extern void intel_edp_psr_update(struct drm_device *dev);
> +extern void hsw_disable_lcpll(struct drm_i915_private *dev_priv,
> + bool switch_to_fclk, bool allow_power_down);
> +extern void hsw_restore_lcpll(struct drm_i915_private *dev_priv);
>
> #endif /* __INTEL_DRV_H__ */
> --
> 1.8.1.2
>
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> Intel-gfx at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx
--
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch
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