[Intel-gfx] [PATCH 1/1] drm/i915: MCHBAR memory info registers are moved since GEN 12.
Matt Roper
matthew.d.roper at intel.com
Thu Feb 13 22:37:31 UTC 2020
On Tue, Feb 11, 2020 at 10:11:42AM -0800, Caz Yokoyama wrote:
> From: "Yokoyama, Caz" <caz.yokoyama at intel.com>
>
> MAD_INTER_CHANNEL_0_0_0_MCHBAR:
> code name offset DRAM_DDR_TYPE
> SKL 0x5000 1:0 DDR4/DDR3/LPDDR3
> TGL 0x6048/0x6248/0xd800 2:0 DDR4/DDR3/LPDDR3/LPDDR4
> ICL 0x5000/0x6048/0x48 2:0 DDR4/DDR3/LPDDR3/LPDDR4
> EHL 0x5000/0x6048 2:0 DDR4/DDR3/LPDDR3/LPDDR4
> CNL 0x5000 2:0 DDR4/DDR3/LPDDR3/LPDDR4
>
> MAD_DIMM_CH0/1_0_0_0_MCHBAR:
> code name offset CH0/1
> SKL 0x500c/0x5010
> TGL 0x6054/0x6058
> EHL 0x500c/0x5010
> ICL 0x500c/0x5010
> The bit definition of MAD_DIMM_CH0/1_0_0_0_MCHBAR is same between
> CNL and TGL.
Have you actually sanity checked the register addresses here on real
hardware? I see the same offsets in the doc as what you've put here,
but since this is a different register database than we get most of our
gfx-specific register details from, it would still be good to double
check that you do indeed get sensible values back when reading from
these addresses before we merge the patch. Especially since the
database indicates that some of these registers are present at multiple
offsets.
>
> P_CR_MC_BIOS_REQ_0_0_0 is same on BXT and GLK in terms of its address and
> bit definition.
> BXT_D_CR_DRP0_DUNIT accesses offset 0x1000, 0x1200, 0x1400, 0x1600.
> Its register name is RAM_ACCESS_DATA1. There is no difference between
> BXT and GLK in terms of its address and bit definition.
>
> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Cc: Matt Roper <matthew.d.roper at intel.com>
> Signed-off-by: Yokoyama, Caz <caz.yokoyama at intel.com>
> ---
> drivers/gpu/drm/i915/i915_drv.c | 15 ++++++++++++---
> drivers/gpu/drm/i915/i915_reg.h | 6 ++++++
> 2 files changed, 18 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
> index 516536234e97..b9418583e503 100644
> --- a/drivers/gpu/drm/i915/i915_drv.c
> +++ b/drivers/gpu/drm/i915/i915_drv.c
> @@ -806,12 +806,18 @@ skl_dram_get_channels_info(struct drm_i915_private *dev_priv)
> u32 val;
> int ret;
>
> - val = I915_READ(SKL_MAD_DIMM_CH0_0_0_0_MCHBAR_MCMAIN);
> + if (INTEL_GEN(dev_priv) >= 12)
> + val = I915_READ(TGL_MAD_DIMM_CH0_0_0_0_MCHBAR);
> + else
> + val = I915_READ(SKL_MAD_DIMM_CH0_0_0_0_MCHBAR_MCMAIN);
> ret = skl_dram_get_channel_info(dev_priv, &ch0, 0, val);
> if (ret == 0)
> dram_info->num_channels++;
>
> - val = I915_READ(SKL_MAD_DIMM_CH1_0_0_0_MCHBAR_MCMAIN);
> + if (INTEL_GEN(dev_priv) >= 12)
> + val = I915_READ(TGL_MAD_DIMM_CH1_0_0_0_MCHBAR);
> + else
> + val = I915_READ(SKL_MAD_DIMM_CH1_0_0_0_MCHBAR_MCMAIN);
> ret = skl_dram_get_channel_info(dev_priv, &ch1, 1, val);
> if (ret == 0)
> dram_info->num_channels++;
> @@ -852,7 +858,10 @@ skl_get_dram_type(struct drm_i915_private *dev_priv)
> {
> u32 val;
>
> - val = I915_READ(SKL_MAD_INTER_CHANNEL_0_0_0_MCHBAR_MCMAIN);
> + if (INTEL_GEN(dev_priv) >= 12)
> + val = I915_READ(TGL_MAD_INTER_CHANNEL_0_0_0_MCHBAR);
> + else
> + val = I915_READ(SKL_MAD_INTER_CHANNEL_0_0_0_MCHBAR_MCMAIN);
>
> switch (val & SKL_DRAM_DDR_TYPE_MASK) {
> case SKL_DRAM_DDR_TYPE_DDR3:
I'm not sure if it might be cleaner to create regs structures for each
platform to centralize the platform-selection logic and avoid all the
if/else in the code. E.g.,
struct i915_mchbar_regs {
i915_reg_t mad_inter_channel;
i915_reg_t mad_dimm_ch0;
i915_reg_t mad_dimm_ch1;
};
static const struct i915_mchbar_regs skl_mchbar_regs = {
.mad_inter_channel = SKL_MAD_INTER_CHANNEL_0_0_0_MCHBAR_MCMAIN,
.mad_dimm_ch0 = SKL_MAD_DIMM_CH0_0_0_0_MCHBAR_MCMAIN,
.mad_dimm_ch1 = SKL_MAD_DIMM_CH1_0_0_0_MCHBAR_MCMAIN,
};
and then use the appropriate regs structure in each of these functions
so that you can just do
val = I915_READ(regs->mad_inter_channel);
and not have to update a bunch of different if-trees if more platforms
show up that move the registers to new offsets.
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index b09c1d6dc0aa..9f6ec44dad6e 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -10508,6 +10508,9 @@ enum skl_power_gate {
> #define SKL_DRAM_DDR_TYPE_LPDDR3 (2 << 0)
> #define SKL_DRAM_DDR_TYPE_LPDDR4 (3 << 0)
>
> +#define TGL_MAD_INTER_CHANNEL_0_0_0_MCHBAR _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x6048)
I'd move this line directly under
SKL_MAD_INTER_CHANNEL_0_0_0_MCHBAR_MCMAIN's definition to help make it
clear that the SKL_DRAM_DDR_TYPE_* bit definitions apply to this
register as well as the SKL variant. And same idea for the CH0/CH1
registers farther down --- move them directly under their SKL variants.
> +#define TGL_DRAM_DDR_TYPE_WIO2 (4 << 0)
This isn't used anywhere and should just be dropped.
> +
> #define SKL_MAD_DIMM_CH0_0_0_0_MCHBAR_MCMAIN _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x500C)
> #define SKL_MAD_DIMM_CH1_0_0_0_MCHBAR_MCMAIN _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x5010)
> #define SKL_DRAM_S_SHIFT 16
> @@ -10535,6 +10538,9 @@ enum skl_power_gate {
> #define CNL_DRAM_RANK_3 (0x2 << 9)
> #define CNL_DRAM_RANK_4 (0x3 << 9)
>
> +#define TGL_MAD_DIMM_CH0_0_0_0_MCHBAR _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x6054)
> +#define TGL_MAD_DIMM_CH1_0_0_0_MCHBAR _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x6058)
> +
> /* Please see hsw_read_dcomp() and hsw_write_dcomp() before using this register,
> * since on HSW we can't write to it using I915_WRITE. */
> #define D_COMP_HSW _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x5F0C)
> --
> 2.21.0.5.gaeb582a983
>
--
Matt Roper
Graphics Software Engineer
VTT-OSGC Platform Enablement
Intel Corporation
(916) 356-2795
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