[096/103] agp/intel: Fix cache control for Sandybridge

From: Greg KH
Date: Fri Oct 22 2010 - 15:01:19 EST


2.6.35-stable review patch. If anyone has any objections, please let us know.

------------------

From: Zhenyu Wang <zhenyuw@xxxxxxxxxxxxxxx>

commit f8f235e5bbf4e61f3e0886a44afb1dc4cfe8f337 upstream.

Sandybridge GTT has new cache control bits in PTE, which controls
graphics page cache in LLC or LLC/MLC, so we need to extend the mask
function to respect the new bits.

And set cache control to always LLC only by default on Gen6.

Signed-off-by: Zhenyu Wang <zhenyuw@xxxxxxxxxxxxxxx>
Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>


---
drivers/char/agp/intel-agp.c | 1
drivers/char/agp/intel-agp.h | 6 ++++
drivers/char/agp/intel-gtt.c | 50 ++++++++++++++++++++++++++++++++--------
drivers/gpu/drm/i915/i915_gem.c | 1
include/linux/intel-gtt.h | 20 ++++++++++++++++
5 files changed, 68 insertions(+), 10 deletions(-)

--- a/drivers/char/agp/intel-agp.c
+++ b/drivers/char/agp/intel-agp.c
@@ -12,6 +12,7 @@
#include <asm/smp.h>
#include "agp.h"
#include "intel-agp.h"
+#include <linux/intel-gtt.h>

#include "intel-gtt.c"

--- a/drivers/char/agp/intel-agp.h
+++ b/drivers/char/agp/intel-agp.h
@@ -60,6 +60,12 @@
#define I810_PTE_LOCAL 0x00000002
#define I810_PTE_VALID 0x00000001
#define I830_PTE_SYSTEM_CACHED 0x00000006
+/* GT PTE cache control fields */
+#define GEN6_PTE_UNCACHED 0x00000002
+#define GEN6_PTE_LLC 0x00000004
+#define GEN6_PTE_LLC_MLC 0x00000006
+#define GEN6_PTE_GFDT 0x00000008
+
#define I810_SMRAM_MISCC 0x70
#define I810_GFX_MEM_WIN_SIZE 0x00010000
#define I810_GFX_MEM_WIN_32M 0x00010000
--- a/drivers/char/agp/intel-gtt.c
+++ b/drivers/char/agp/intel-gtt.c
@@ -49,6 +49,26 @@ static struct gatt_mask intel_i810_masks
.type = INTEL_AGP_CACHED_MEMORY}
};

+#define INTEL_AGP_UNCACHED_MEMORY 0
+#define INTEL_AGP_CACHED_MEMORY_LLC 1
+#define INTEL_AGP_CACHED_MEMORY_LLC_GFDT 2
+#define INTEL_AGP_CACHED_MEMORY_LLC_MLC 3
+#define INTEL_AGP_CACHED_MEMORY_LLC_MLC_GFDT 4
+
+static struct gatt_mask intel_gen6_masks[] =
+{
+ {.mask = I810_PTE_VALID | GEN6_PTE_UNCACHED,
+ .type = INTEL_AGP_UNCACHED_MEMORY },
+ {.mask = I810_PTE_VALID | GEN6_PTE_LLC,
+ .type = INTEL_AGP_CACHED_MEMORY_LLC },
+ {.mask = I810_PTE_VALID | GEN6_PTE_LLC | GEN6_PTE_GFDT,
+ .type = INTEL_AGP_CACHED_MEMORY_LLC_GFDT },
+ {.mask = I810_PTE_VALID | GEN6_PTE_LLC_MLC,
+ .type = INTEL_AGP_CACHED_MEMORY_LLC_MLC },
+ {.mask = I810_PTE_VALID | GEN6_PTE_LLC_MLC | GEN6_PTE_GFDT,
+ .type = INTEL_AGP_CACHED_MEMORY_LLC_MLC_GFDT },
+};
+
static struct _intel_private {
struct pci_dev *pcidev; /* device one */
u8 __iomem *registers;
@@ -175,13 +195,6 @@ static void intel_agp_insert_sg_entries(
off_t pg_start, int mask_type)
{
int i, j;
- u32 cache_bits = 0;
-
- if (agp_bridge->dev->device == PCI_DEVICE_ID_INTEL_SANDYBRIDGE_HB ||
- agp_bridge->dev->device == PCI_DEVICE_ID_INTEL_SANDYBRIDGE_M_HB)
- {
- cache_bits = I830_PTE_SYSTEM_CACHED;
- }

for (i = 0, j = pg_start; i < mem->page_count; i++, j++) {
writel(agp_bridge->driver->mask_memory(agp_bridge,
@@ -314,6 +327,23 @@ static int intel_i830_type_to_mask_type(
return 0;
}

+static int intel_gen6_type_to_mask_type(struct agp_bridge_data *bridge,
+ int type)
+{
+ unsigned int type_mask = type & ~AGP_USER_CACHED_MEMORY_GFDT;
+ unsigned int gfdt = type & AGP_USER_CACHED_MEMORY_GFDT;
+
+ if (type_mask == AGP_USER_UNCACHED_MEMORY)
+ return INTEL_AGP_UNCACHED_MEMORY;
+ else if (type_mask == AGP_USER_CACHED_MEMORY_LLC_MLC)
+ return gfdt ? INTEL_AGP_CACHED_MEMORY_LLC_MLC_GFDT :
+ INTEL_AGP_CACHED_MEMORY_LLC_MLC;
+ else /* set 'normal'/'cached' to LLC by default */
+ return gfdt ? INTEL_AGP_CACHED_MEMORY_LLC_GFDT :
+ INTEL_AGP_CACHED_MEMORY_LLC;
+}
+
+
static int intel_i810_insert_entries(struct agp_memory *mem, off_t pg_start,
int type)
{
@@ -1155,7 +1185,7 @@ static int intel_i915_insert_entries(str

mask_type = agp_bridge->driver->agp_type_to_mask_type(agp_bridge, type);

- if (mask_type != 0 && mask_type != AGP_PHYS_MEMORY &&
+ if (!IS_SNB && mask_type != 0 && mask_type != AGP_PHYS_MEMORY &&
mask_type != INTEL_AGP_CACHED_MEMORY)
goto out_err;

@@ -1546,7 +1576,7 @@ static const struct agp_bridge_driver in
.fetch_size = intel_i9xx_fetch_size,
.cleanup = intel_i915_cleanup,
.mask_memory = intel_gen6_mask_memory,
- .masks = intel_i810_masks,
+ .masks = intel_gen6_masks,
.agp_enable = intel_i810_agp_enable,
.cache_flush = global_cache_flush,
.create_gatt_table = intel_i965_create_gatt_table,
@@ -1559,7 +1589,7 @@ static const struct agp_bridge_driver in
.agp_alloc_pages = agp_generic_alloc_pages,
.agp_destroy_page = agp_generic_destroy_page,
.agp_destroy_pages = agp_generic_destroy_pages,
- .agp_type_to_mask_type = intel_i830_type_to_mask_type,
+ .agp_type_to_mask_type = intel_gen6_type_to_mask_type,
.chipset_flush = intel_i915_chipset_flush,
#ifdef USE_PCI_DMA_API
.agp_map_page = intel_agp_map_page,
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -34,6 +34,7 @@
#include <linux/slab.h>
#include <linux/swap.h>
#include <linux/pci.h>
+#include <linux/intel-gtt.h>

static void i915_gem_object_flush_gpu_write_domain(struct drm_gem_object *obj);
static void i915_gem_object_flush_gtt_write_domain(struct drm_gem_object *obj);
--- /dev/null
+++ b/include/linux/intel-gtt.h
@@ -0,0 +1,20 @@
+/*
+ * Common Intel AGPGART and GTT definitions.
+ */
+#ifndef _INTEL_GTT_H
+#define _INTEL_GTT_H
+
+#include <linux/agp_backend.h>
+
+/* This is for Intel only GTT controls.
+ *
+ * Sandybridge: AGP_USER_CACHED_MEMORY default to LLC only
+ */
+
+#define AGP_USER_CACHED_MEMORY_LLC_MLC (AGP_USER_TYPES + 2)
+#define AGP_USER_UNCACHED_MEMORY (AGP_USER_TYPES + 4)
+
+/* flag for GFDT type */
+#define AGP_USER_CACHED_MEMORY_GFDT (1 << 3)
+
+#endif


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