From: Ville Syrjälä Date: Thu, 14 Aug 2014 22:21:55 +0000 (+0300) Subject: drm/i915: Idle unused rings on gen2/3 during init/resume X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=81e7f2002b7db269799ebdac0d905574c0a85d1d;p=linux-beck.git drm/i915: Idle unused rings on gen2/3 during init/resume gen2/3 platforms have a boatload of rings we're not using. On my 830 the BIOS/hw can leave some of those "active" after resume which will prevent c3 entry. The ring is apparently considered active whenever head != tail even if the ring is disabled. Disable and clear all such unused ringbuffers on init/resume. Signed-off-by: Ville Syrjälä Signed-off-by: Daniel Vetter --- diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 60b8bd1717db..6c685708a516 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -4663,11 +4663,46 @@ intel_enable_blt(struct drm_device *dev) return true; } +static void init_unused_ring(struct drm_device *dev, u32 base) +{ + struct drm_i915_private *dev_priv = dev->dev_private; + + I915_WRITE(RING_CTL(base), 0); + I915_WRITE(RING_HEAD(base), 0); + I915_WRITE(RING_TAIL(base), 0); + I915_WRITE(RING_START(base), 0); +} + +static void init_unused_rings(struct drm_device *dev) +{ + if (IS_I830(dev)) { + init_unused_ring(dev, PRB1_BASE); + init_unused_ring(dev, SRB0_BASE); + init_unused_ring(dev, SRB1_BASE); + init_unused_ring(dev, SRB2_BASE); + init_unused_ring(dev, SRB3_BASE); + } else if (IS_GEN2(dev)) { + init_unused_ring(dev, SRB0_BASE); + init_unused_ring(dev, SRB1_BASE); + } else if (IS_GEN3(dev)) { + init_unused_ring(dev, PRB1_BASE); + init_unused_ring(dev, PRB2_BASE); + } +} + int i915_gem_init_rings(struct drm_device *dev) { struct drm_i915_private *dev_priv = dev->dev_private; int ret; + /* + * At least 830 can leave some of the unused rings + * "active" (ie. head != tail) after resume which + * will prevent c3 entry. Makes sure all unused rings + * are totally idle. + */ + init_unused_rings(dev); + ret = intel_init_render_ring_buffer(dev); if (ret) return ret; diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index b7b2e63c14d0..15c0eaa9f97f 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -1026,6 +1026,13 @@ enum punit_power_well { #define PGTBL_ADDRESS_LO_MASK 0xfffff000 /* bits [31:12] */ #define PGTBL_ADDRESS_HI_MASK 0x000000f0 /* bits [35:32] (gen4) */ #define PGTBL_ER 0x02024 +#define PRB0_BASE (0x2030-0x30) +#define PRB1_BASE (0x2040-0x30) /* 830,gen3 */ +#define PRB2_BASE (0x2050-0x30) /* gen3 */ +#define SRB0_BASE (0x2100-0x30) /* gen2 */ +#define SRB1_BASE (0x2110-0x30) /* gen2 */ +#define SRB2_BASE (0x2120-0x30) /* 830 */ +#define SRB3_BASE (0x2130-0x30) /* 830 */ #define RENDER_RING_BASE 0x02000 #define BSD_RING_BASE 0x04000 #define GEN6_BSD_RING_BASE 0x12000