From d351f6d94893f3ba98b1b20c5ef44c35fc1da124 Mon Sep 17 00:00:00 2001 From: Francisco Jerez Date: Fri, 29 May 2015 16:44:15 +0300 Subject: [PATCH] drm/i915: Add SCRATCH1 and ROW_CHICKEN3 to the register whitelist. Only bit 27 of SCRATCH1 and bit 6 of ROW_CHICKEN3 are allowed to be set because of security-sensitive bits we don't want userspace to mess with. On HSW hardware the whitelisted bits control whether atomic read-modify-write operations are performed on L3 or on GTI, and when set to L3 (which can be 10x-30x better performing than on GTI, depending on the application) require great care to avoid a system hang, so we currently program them to be handled on GTI by default. Beignet can immediately start taking advantage of this change to enable L3 atomics. Mesa should eventually switch to L3 atomics too, but a number of non-trivial changes are still required so it will continue using GTI atomics for now. Signed-off-by: Francisco Jerez Reviewed-by: Zhigang Gong Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/i915_cmd_parser.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_cmd_parser.c b/drivers/gpu/drm/i915/i915_cmd_parser.c index cafa3e2f16fc..306d9e4e5cf3 100644 --- a/drivers/gpu/drm/i915/i915_cmd_parser.c +++ b/drivers/gpu/drm/i915/i915_cmd_parser.c @@ -463,6 +463,13 @@ static const struct drm_i915_reg_descriptor gen7_render_regs[] = { REG32(GEN7_L3SQCREG1), REG32(GEN7_L3CNTLREG2), REG32(GEN7_L3CNTLREG3), + REG32(HSW_SCRATCH1, + .mask = ~HSW_SCRATCH1_L3_DATA_ATOMICS_DISABLE, + .value = 0), + REG32(HSW_ROW_CHICKEN3, + .mask = ~(HSW_ROW_CHICKEN3_L3_GLOBAL_ATOMICS_DISABLE << 16 | + HSW_ROW_CHICKEN3_L3_GLOBAL_ATOMICS_DISABLE), + .value = 0), }; static const struct drm_i915_reg_descriptor gen7_blt_regs[] = { -- 2.30.2