From 231b1d6c9ab6ff23f7a1826835946dd2b0f57156 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Tue, 6 Jun 2023 22:14:52 +0300 Subject: [PATCH] drm/i915/dsb: Don't use indexed writes when byte enables are not all set MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The indexed write instruction doesn't support byte-enables, so if the non-indexed write used those we must not convert it to an indexed write. Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20230606191504.18099-8-ville.syrjala@linux.intel.com Reviewed-by: Animesh Manna --- drivers/gpu/drm/i915/display/intel_dsb.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dsb.c b/drivers/gpu/drm/i915/display/intel_dsb.c index 3de0d572c511a..9a507b9ad82ca 100644 --- a/drivers/gpu/drm/i915/display/intel_dsb.c +++ b/drivers/gpu/drm/i915/display/intel_dsb.c @@ -145,7 +145,7 @@ static bool intel_dsb_prev_ins_is_write(struct intel_dsb *dsb, if (dsb->free_pos == 0) return false; - prev_opcode = buf[dsb->ins_start_offset + 1] >> DSB_OPCODE_SHIFT; + prev_opcode = buf[dsb->ins_start_offset + 1] & ~DSB_REG_VALUE_MASK; prev_reg = buf[dsb->ins_start_offset + 1] & DSB_REG_VALUE_MASK; return prev_opcode == opcode && prev_reg == i915_mmio_reg_offset(reg); @@ -153,12 +153,18 @@ static bool intel_dsb_prev_ins_is_write(struct intel_dsb *dsb, static bool intel_dsb_prev_ins_is_mmio_write(struct intel_dsb *dsb, i915_reg_t reg) { - return intel_dsb_prev_ins_is_write(dsb, DSB_OPCODE_MMIO_WRITE, reg); + /* only full byte-enables can be converted to indexed writes */ + return intel_dsb_prev_ins_is_write(dsb, + DSB_OPCODE_MMIO_WRITE << DSB_OPCODE_SHIFT | + DSB_BYTE_EN << DSB_BYTE_EN_SHIFT, + reg); } static bool intel_dsb_prev_ins_is_indexed_write(struct intel_dsb *dsb, i915_reg_t reg) { - return intel_dsb_prev_ins_is_write(dsb, DSB_OPCODE_INDEXED_WRITE, reg); + return intel_dsb_prev_ins_is_write(dsb, + DSB_OPCODE_INDEXED_WRITE << DSB_OPCODE_SHIFT, + reg); } /** -- 2.30.2