From 3e69935fc7c0a32f72f75160163aa80df1b143f5 Mon Sep 17 00:00:00 2001
From: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Date: Tue, 24 Aug 2021 13:30:27 -0400
Subject: drm/panfrost: Clamp lock region to Bifrost minimum
Git-commit: bd7ffbc3ca12629aeb66fb9e28cf42b7f37e3e3b
Patch-mainline: v5.15-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
When locking a region, we currently clamp to a PAGE_SIZE as the minimum
lock region. While this is valid for Midgard, it is invalid for Bifrost,
where the minimum locking size is 8x larger than the 4k page size. Add a
hardware definition for the minimum lock region size (corresponding to
KBASE_LOCK_REGION_MIN_SIZE_LOG2 in kbase) and respect it.
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Tested-by: Chris Morgan <macromorgan@hotmail.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Steven Price <steven.price@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210824173028.7528-4-alyssa.rosenzweig@collabora.com
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/panfrost/panfrost_mmu.c | 2 +-
drivers/gpu/drm/panfrost/panfrost_regs.h | 2 ++
2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c
index 3a795273e505..dfe5f1d29763 100644
--- a/drivers/gpu/drm/panfrost/panfrost_mmu.c
+++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c
@@ -66,7 +66,7 @@ static void lock_region(struct panfrost_device *pfdev, u32 as_nr,
/* The size is encoded as ceil(log2) minus(1), which may be calculated
* with fls. The size must be clamped to hardware bounds.
*/
- size = max_t(u64, size, PAGE_SIZE);
+ size = max_t(u64, size, AS_LOCK_REGION_MIN_SIZE);
region_width = fls64(size - 1) - 1;
region |= region_width;
diff --git a/drivers/gpu/drm/panfrost/panfrost_regs.h b/drivers/gpu/drm/panfrost/panfrost_regs.h
index 1940ff86e49a..6c5a11ef1ee8 100644
--- a/drivers/gpu/drm/panfrost/panfrost_regs.h
+++ b/drivers/gpu/drm/panfrost/panfrost_regs.h
@@ -316,6 +316,8 @@
#define AS_FAULTSTATUS_ACCESS_TYPE_READ (0x2 << 8)
#define AS_FAULTSTATUS_ACCESS_TYPE_WRITE (0x3 << 8)
+#define AS_LOCK_REGION_MIN_SIZE (1ULL << 15)
+
#define gpu_write(dev, reg, data) writel(data, dev->iomem + reg)
#define gpu_read(dev, reg) readl(dev->iomem + reg)
--
2.38.1