Commit 1e40d4ae authored by Yunwei Zhang's avatar Yunwei Zhang Committed by Mika Kuoppala

drm/i915/cnl: Implement WaProgramMgsrForCorrectSliceSpecificMmioReads

WaProgramMgsrForCorrectSliceSpecificMmioReads dictate that before any MMIO
read into Slice/Subslice specific registers, MCR packet control
register(0xFDC) needs to be programmed to point to any enabled
slice/subslice pair. Otherwise, incorrect value will be returned.

However, that means each subsequent MMIO read will be forwarded to a
specific slice/subslice combination as read is unicast. This is OK since
slice/subslice specific register values are consistent in almost all cases
across slice/subslice. There are rare occasions such as INSTDONE that this
value will be dependent on slice/subslice combo, in such cases, we need to
program 0xFDC and recover this after. This is already covered by
read_subslice_reg.

Also, 0xFDC will lose its information after TDR/engine reset/power state
change.

References: HSD#1405586840, BSID#0575

v2:
 - use fls() instead of find_last_bit() (Chris)
 - added INTEL_SSEU to extract sseu from device info. (Chris)
v3:
 - rebase on latest tip
v5:
 - Added references (Mika)
 - Change the ordered of passing arguments and etc. (Ursulin)
v7:
 - Moved WA explanation Comments(Oscar)
 - Rebased.
v8:
 - Renamed sanitize_mcr to calculate_s_ss_select. (Oscar)
 - calculate s/ss selector instead of whole mcr. (Oscar)
v9:
 - Updated function name (Oscar)
 - Remove redundant variables (Oscar)
v10:
 - Separate pre-GEN10 and GEN11 mask. (Oscar)

Cc: Oscar Mateo <oscar.mateo@intel.com>
Cc: Michel Thierry <michel.thierry@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: default avatarYunwei Zhang <yunwei.zhang@intel.com>
Reviewed-by: default avatarOscar Mateo <oscar.mateo@intel.com>
Signed-off-by: default avatarMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1526683197-24656-1-git-send-email-yunwei.zhang@intel.com
parent c894d63c
...@@ -2743,6 +2743,8 @@ int vlv_force_gfx_clock(struct drm_i915_private *dev_priv, bool on); ...@@ -2743,6 +2743,8 @@ int vlv_force_gfx_clock(struct drm_i915_private *dev_priv, bool on);
int intel_engines_init_mmio(struct drm_i915_private *dev_priv); int intel_engines_init_mmio(struct drm_i915_private *dev_priv);
int intel_engines_init(struct drm_i915_private *dev_priv); int intel_engines_init(struct drm_i915_private *dev_priv);
u32 intel_calculate_mcr_s_ss_select(struct drm_i915_private *dev_priv);
/* intel_hotplug.c */ /* intel_hotplug.c */
void intel_hpd_irq_handler(struct drm_i915_private *dev_priv, void intel_hpd_irq_handler(struct drm_i915_private *dev_priv,
u32 pin_mask, u32 long_mask); u32 pin_mask, u32 long_mask);
......
...@@ -819,12 +819,29 @@ const char *i915_cache_level_str(struct drm_i915_private *i915, int type) ...@@ -819,12 +819,29 @@ const char *i915_cache_level_str(struct drm_i915_private *i915, int type)
} }
} }
u32 intel_calculate_mcr_s_ss_select(struct drm_i915_private *dev_priv)
{
const struct sseu_dev_info *sseu = &(INTEL_INFO(dev_priv)->sseu);
u32 mcr_s_ss_select;
u32 slice = fls(sseu->slice_mask);
u32 subslice = fls(sseu->subslice_mask[slice]);
if (INTEL_GEN(dev_priv) == 10)
mcr_s_ss_select = GEN8_MCR_SLICE(slice) |
GEN8_MCR_SUBSLICE(subslice);
else
mcr_s_ss_select = 0;
return mcr_s_ss_select;
}
static inline uint32_t static inline uint32_t
read_subslice_reg(struct drm_i915_private *dev_priv, int slice, read_subslice_reg(struct drm_i915_private *dev_priv, int slice,
int subslice, i915_reg_t reg) int subslice, i915_reg_t reg)
{ {
uint32_t mcr_slice_subslice_mask; uint32_t mcr_slice_subslice_mask;
uint32_t mcr_slice_subslice_select; uint32_t mcr_slice_subslice_select;
uint32_t default_mcr_s_ss_select;
uint32_t mcr; uint32_t mcr;
uint32_t ret; uint32_t ret;
enum forcewake_domains fw_domains; enum forcewake_domains fw_domains;
...@@ -841,6 +858,8 @@ read_subslice_reg(struct drm_i915_private *dev_priv, int slice, ...@@ -841,6 +858,8 @@ read_subslice_reg(struct drm_i915_private *dev_priv, int slice,
GEN8_MCR_SUBSLICE(subslice); GEN8_MCR_SUBSLICE(subslice);
} }
default_mcr_s_ss_select = intel_calculate_mcr_s_ss_select(dev_priv);
fw_domains = intel_uncore_forcewake_for_reg(dev_priv, reg, fw_domains = intel_uncore_forcewake_for_reg(dev_priv, reg,
FW_REG_READ); FW_REG_READ);
fw_domains |= intel_uncore_forcewake_for_reg(dev_priv, fw_domains |= intel_uncore_forcewake_for_reg(dev_priv,
...@@ -851,11 +870,10 @@ read_subslice_reg(struct drm_i915_private *dev_priv, int slice, ...@@ -851,11 +870,10 @@ read_subslice_reg(struct drm_i915_private *dev_priv, int slice,
intel_uncore_forcewake_get__locked(dev_priv, fw_domains); intel_uncore_forcewake_get__locked(dev_priv, fw_domains);
mcr = I915_READ_FW(GEN8_MCR_SELECTOR); mcr = I915_READ_FW(GEN8_MCR_SELECTOR);
/*
* The HW expects the slice and sublice selectors to be reset to 0 WARN_ON_ONCE((mcr & mcr_slice_subslice_mask) !=
* after reading out the registers. default_mcr_s_ss_select);
*/
WARN_ON_ONCE(mcr & mcr_slice_subslice_mask);
mcr &= ~mcr_slice_subslice_mask; mcr &= ~mcr_slice_subslice_mask;
mcr |= mcr_slice_subslice_select; mcr |= mcr_slice_subslice_select;
I915_WRITE_FW(GEN8_MCR_SELECTOR, mcr); I915_WRITE_FW(GEN8_MCR_SELECTOR, mcr);
...@@ -863,6 +881,8 @@ read_subslice_reg(struct drm_i915_private *dev_priv, int slice, ...@@ -863,6 +881,8 @@ read_subslice_reg(struct drm_i915_private *dev_priv, int slice,
ret = I915_READ_FW(reg); ret = I915_READ_FW(reg);
mcr &= ~mcr_slice_subslice_mask; mcr &= ~mcr_slice_subslice_mask;
mcr |= default_mcr_s_ss_select;
I915_WRITE_FW(GEN8_MCR_SELECTOR, mcr); I915_WRITE_FW(GEN8_MCR_SELECTOR, mcr);
intel_uncore_forcewake_put__locked(dev_priv, fw_domains); intel_uncore_forcewake_put__locked(dev_priv, fw_domains);
......
...@@ -672,8 +672,35 @@ static void cfl_gt_workarounds_apply(struct drm_i915_private *dev_priv) ...@@ -672,8 +672,35 @@ static void cfl_gt_workarounds_apply(struct drm_i915_private *dev_priv)
GAMT_ECO_ENABLE_IN_PLACE_DECOMPRESS); GAMT_ECO_ENABLE_IN_PLACE_DECOMPRESS);
} }
static void wa_init_mcr(struct drm_i915_private *dev_priv)
{
u32 mcr;
u32 mcr_slice_subslice_mask;
mcr = I915_READ(GEN8_MCR_SELECTOR);
mcr_slice_subslice_mask = GEN8_MCR_SLICE_MASK |
GEN8_MCR_SUBSLICE_MASK;
/*
* WaProgramMgsrForCorrectSliceSpecificMmioReads:cnl
* Before any MMIO read into slice/subslice specific registers, MCR
* packet control register needs to be programmed to point to any
* enabled s/ss pair. Otherwise, incorrect values will be returned.
* This means each subsequent MMIO read will be forwarded to an
* specific s/ss combination, but this is OK since these registers
* are consistent across s/ss in almost all cases. In the rare
* occasions, such as INSTDONE, where this value is dependent
* on s/ss combo, the read should be done with read_subslice_reg.
*/
mcr &= ~mcr_slice_subslice_mask;
mcr |= intel_calculate_mcr_s_ss_select(dev_priv);
I915_WRITE(GEN8_MCR_SELECTOR, mcr);
}
static void cnl_gt_workarounds_apply(struct drm_i915_private *dev_priv) static void cnl_gt_workarounds_apply(struct drm_i915_private *dev_priv)
{ {
wa_init_mcr(dev_priv);
/* WaDisableI2mCycleOnWRPort:cnl (pre-prod) */ /* WaDisableI2mCycleOnWRPort:cnl (pre-prod) */
if (IS_CNL_REVID(dev_priv, CNL_REVID_B0, CNL_REVID_B0)) if (IS_CNL_REVID(dev_priv, CNL_REVID_B0, CNL_REVID_B0))
I915_WRITE(GAMT_CHKN_BIT_REG, I915_WRITE(GAMT_CHKN_BIT_REG,
......
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