On 2022-05-02 at 16:40:00 +0530, Ramalingam C wrote:
> From: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
>
> Even though the initial protocontext we load onto HW has the register
> cleared, by the time we save it into the default image, BB_OFFSET has
> had the enable bit set. Reclear BB_OFFSET for each new context.
>
> Testcase: igt/i915_selftests/gt_lrc
>
> v2:
> Extend it for gen8.
> v3:
> BB_OFFSET is recorded per engine from Gen9 onwards
>
> Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
> Cc: Mika Kuoppala <mika.kuoppala@xxxxxxxxxxxxxxx>
> Signed-off-by: Ramalingam C <ramalingam.c@xxxxxxxxx>
> Reviewed-by: Thomas Hellstrom <thomas.hellstrom@xxxxxxxxxxxxxxx>
Thomas,
Could you please reconfirm your R-b for v3? This R-b was given for v1.
Ram
> ---
> drivers/gpu/drm/i915/gt/intel_engine_regs.h | 1 +
> drivers/gpu/drm/i915/gt/intel_lrc.c | 20 ++++++++++++++++++++
> drivers/gpu/drm/i915/gt/selftest_lrc.c | 5 +++++
> 3 files changed, 26 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/gt/intel_engine_regs.h b/drivers/gpu/drm/i915/gt/intel_engine_regs.h
> index 75a0c55c5aa5..8c65f3a7acfb 100644
> --- a/drivers/gpu/drm/i915/gt/intel_engine_regs.h
> +++ b/drivers/gpu/drm/i915/gt/intel_engine_regs.h
> @@ -109,6 +109,7 @@
> #define RING_SBBSTATE(base) _MMIO((base) + 0x118) /* hsw+ */
> #define RING_SBBADDR_UDW(base) _MMIO((base) + 0x11c) /* gen8+ */
> #define RING_BBADDR(base) _MMIO((base) + 0x140)
> +#define RING_BB_OFFSET(base) _MMIO((base) + 0x158)
> #define RING_BBADDR_UDW(base) _MMIO((base) + 0x168) /* gen8+ */
> #define CCID(base) _MMIO((base) + 0x180)
> #define CCID_EN BIT(0)
> diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
> index eec73c66406c..ee8ab7470a62 100644
> --- a/drivers/gpu/drm/i915/gt/intel_lrc.c
> +++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
> @@ -662,6 +662,21 @@ static int lrc_ring_mi_mode(const struct intel_engine_cs *engine)
> return -1;
> }
>
> +static int lrc_ring_bb_offset(const struct intel_engine_cs *engine)
> +{
> + if (GRAPHICS_VER_FULL(engine->i915) >= IP_VER(12, 50))
> + return 0x80;
> + else if (GRAPHICS_VER(engine->i915) >= 12)
> + return 0x70;
> + else if (GRAPHICS_VER(engine->i915) >= 9)
> + return 0x64;
> + else if (GRAPHICS_VER(engine->i915) >= 8 &&
> + engine->class == RENDER_CLASS)
> + return 0xc4;
> + else
> + return -1;
> +}
> +
> static int lrc_ring_gpr0(const struct intel_engine_cs *engine)
> {
> if (GRAPHICS_VER_FULL(engine->i915) >= IP_VER(12, 50))
> @@ -768,6 +783,7 @@ static void init_common_regs(u32 * const regs,
> bool inhibit)
> {
> u32 ctl;
> + int loc;
>
> ctl = _MASKED_BIT_ENABLE(CTX_CTRL_INHIBIT_SYN_CTX_SWITCH);
> ctl |= _MASKED_BIT_DISABLE(CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT);
> @@ -779,6 +795,10 @@ static void init_common_regs(u32 * const regs,
> regs[CTX_CONTEXT_CONTROL] = ctl;
>
> regs[CTX_TIMESTAMP] = ce->stats.runtime.last;
> +
> + loc = lrc_ring_bb_offset(engine);
> + if (loc != -1)
> + regs[loc + 1] = 0;
> }
>
> static void init_wa_bb_regs(u32 * const regs,
> diff --git a/drivers/gpu/drm/i915/gt/selftest_lrc.c b/drivers/gpu/drm/i915/gt/selftest_lrc.c
> index 8b2c11dbe354..c4bd4e1ac5ef 100644
> --- a/drivers/gpu/drm/i915/gt/selftest_lrc.c
> +++ b/drivers/gpu/drm/i915/gt/selftest_lrc.c
> @@ -357,6 +357,11 @@ static int live_lrc_fixed(void *arg)
> lrc_ring_cmd_buf_cctl(engine),
> "RING_CMD_BUF_CCTL"
> },
> + {
> + i915_mmio_reg_offset(RING_BB_OFFSET(engine->mmio_base)),
> + lrc_ring_bb_offset(engine),
> + "RING_BB_OFFSET"
> + },
> { },
> }, *t;
> u32 *hw;
> --
> 2.20.1
>
