[PATCH AUTOSEL 6.7 43/58] accel/ivpu: Force snooping for MMU writes

From: Sasha Levin
Date: Mon Feb 12 2024 - 19:30:54 EST


From: "Wachowski, Karol" <karol.wachowski@xxxxxxxxx>

[ Upstream commit c9da9a1f17bf4fa96b115950fd389c917b583c1c ]

Set AW_SNOOP_OVERRIDE bit in VPU_37/40XX_HOST_IF_TCU_PTW_OVERRIDES
to force snooping for MMU write accesses (setting event queue events).

MMU event queue buffer is the only buffer written by MMU and
mapped as write-back which break cache coherency. Force write
transactions to be snooped solving the problem.

Signed-off-by: Wachowski, Karol <karol.wachowski@xxxxxxxxx>
Signed-off-by: Jacek Lawrynowicz <jacek.lawrynowicz@xxxxxxxxxxxxxxx>
Reviewed-by: Jeffrey Hugo <quic_jhugo@xxxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20240126122804.2169129-2-jacek.lawrynowicz@xxxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/accel/ivpu/ivpu_hw_37xx.c | 2 +-
drivers/accel/ivpu/ivpu_hw_40xx.c | 2 +-
drivers/accel/ivpu/ivpu_mmu.c | 3 ---
3 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/accel/ivpu/ivpu_hw_37xx.c b/drivers/accel/ivpu/ivpu_hw_37xx.c
index d530384f8d60..e658fcf849f7 100644
--- a/drivers/accel/ivpu/ivpu_hw_37xx.c
+++ b/drivers/accel/ivpu/ivpu_hw_37xx.c
@@ -523,7 +523,7 @@ static void ivpu_boot_no_snoop_enable(struct ivpu_device *vdev)
u32 val = REGV_RD32(VPU_37XX_HOST_IF_TCU_PTW_OVERRIDES);

val = REG_SET_FLD(VPU_37XX_HOST_IF_TCU_PTW_OVERRIDES, NOSNOOP_OVERRIDE_EN, val);
- val = REG_SET_FLD(VPU_37XX_HOST_IF_TCU_PTW_OVERRIDES, AW_NOSNOOP_OVERRIDE, val);
+ val = REG_CLR_FLD(VPU_37XX_HOST_IF_TCU_PTW_OVERRIDES, AW_NOSNOOP_OVERRIDE, val);
val = REG_SET_FLD(VPU_37XX_HOST_IF_TCU_PTW_OVERRIDES, AR_NOSNOOP_OVERRIDE, val);

REGV_WR32(VPU_37XX_HOST_IF_TCU_PTW_OVERRIDES, val);
diff --git a/drivers/accel/ivpu/ivpu_hw_40xx.c b/drivers/accel/ivpu/ivpu_hw_40xx.c
index e691c49c9841..8a7440bcd6df 100644
--- a/drivers/accel/ivpu/ivpu_hw_40xx.c
+++ b/drivers/accel/ivpu/ivpu_hw_40xx.c
@@ -526,7 +526,7 @@ static void ivpu_boot_no_snoop_enable(struct ivpu_device *vdev)
u32 val = REGV_RD32(VPU_40XX_HOST_IF_TCU_PTW_OVERRIDES);

val = REG_SET_FLD(VPU_40XX_HOST_IF_TCU_PTW_OVERRIDES, SNOOP_OVERRIDE_EN, val);
- val = REG_CLR_FLD(VPU_40XX_HOST_IF_TCU_PTW_OVERRIDES, AW_SNOOP_OVERRIDE, val);
+ val = REG_SET_FLD(VPU_40XX_HOST_IF_TCU_PTW_OVERRIDES, AW_SNOOP_OVERRIDE, val);
val = REG_CLR_FLD(VPU_40XX_HOST_IF_TCU_PTW_OVERRIDES, AR_SNOOP_OVERRIDE, val);

REGV_WR32(VPU_40XX_HOST_IF_TCU_PTW_OVERRIDES, val);
diff --git a/drivers/accel/ivpu/ivpu_mmu.c b/drivers/accel/ivpu/ivpu_mmu.c
index 2538c78fbebe..9898946174fd 100644
--- a/drivers/accel/ivpu/ivpu_mmu.c
+++ b/drivers/accel/ivpu/ivpu_mmu.c
@@ -533,7 +533,6 @@ static int ivpu_mmu_reset(struct ivpu_device *vdev)
mmu->cmdq.cons = 0;

memset(mmu->evtq.base, 0, IVPU_MMU_EVTQ_SIZE);
- clflush_cache_range(mmu->evtq.base, IVPU_MMU_EVTQ_SIZE);
mmu->evtq.prod = 0;
mmu->evtq.cons = 0;

@@ -847,8 +846,6 @@ static u32 *ivpu_mmu_get_event(struct ivpu_device *vdev)
if (!CIRC_CNT(IVPU_MMU_Q_IDX(evtq->prod), IVPU_MMU_Q_IDX(evtq->cons), IVPU_MMU_Q_COUNT))
return NULL;

- clflush_cache_range(evt, IVPU_MMU_EVTQ_CMD_SIZE);
-
evtq->cons = (evtq->cons + 1) & IVPU_MMU_Q_WRAP_MASK;
REGV_WR32(IVPU_MMU_REG_EVTQ_CONS_SEC, evtq->cons);

--
2.43.0