/*
* Copyright © 2008-2012 Intel Corporation
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*
* Authors:
* Eric Anholt <eric@anholt.net>
* Chris Wilson <chris@chris-wilson.co.uk>
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <dev/drm2/drmP.h>
#include <dev/drm2/i915/i915_drm.h>
#include <dev/drm2/i915/i915_drv.h>
/*
* The BIOS typically reserves some of the system's memory for the exclusive
* use of the integrated graphics. This memory is no longer available for
* use by the OS and so the user finds that his system has less memory
* available than he put in. We refer to this memory as stolen.
*
* The BIOS will allocate its framebuffer from the stolen memory. Our
* goal is try to reuse that object for our own fbcon which must always
* be available for panics. Anything else we can reuse the stolen memory
* for is a boon.
*/
static unsigned long i915_stolen_to_physical(struct drm_device *dev)
{
u32 base;
/* On the machines I have tested the Graphics Base of Stolen Memory
* is unreliable, so on those compute the base by subtracting the
* stolen memory from the Top of Low Usable DRAM which is where the
* BIOS places the graphics stolen memory.
*
* On gen2, the layout is slightly different with the Graphics Segment
* immediately following Top of Memory (or Top of Usable DRAM). Note
* it appears that TOUD is only reported by 865g, so we just use the
* top of memory as determined by the e820 probe.
*
* XXX gen2 requires an unavailable symbol and 945gm fails with
* its value of TOLUD.
*/
base = 0;
if (INTEL_INFO(dev)->gen >= 6) {
/* Read Base Data of Stolen Memory Register (BDSM) directly.
* Note that there is also a MCHBAR miror at 0x1080c0 or
* we could use device 2:0x5c instead.
*/
pci_read_config_dword(dev->dev, 0xB0, &base);
base &= ~4095; /* lower bits used for locking register */
} else if (INTEL_INFO(dev)->gen > 3 || IS_G33(dev)) {
/* Read Graphics Base of Stolen Memory directly */
pci_read_config_dword(dev->dev, 0xA4, &base);
#if 0
} else if (IS_GEN3(dev)) {
u8 val;
/* Stolen is immediately below Top of Low Usable DRAM */
pci_read_config_byte(pdev, 0x9c, &val);
base = val >> 3 << 27;
base -= dev_priv->mm.gtt->stolen_size;
} else {
/* Stolen is immediately above Top of Memory */
base = max_low_pfn_mapped << PAGE_SHIFT;
#endif
}
return base;
}
static void i915_warn_stolen(struct drm_device *dev)
{
DRM_INFO("not enough stolen space for compressed buffer, disabling\n");
DRM_INFO("hint: you may be able to increase stolen memory size in the BIOS to avoid this\n");
}
static void i915_setup_compression(struct drm_device *dev, int size)
{
struct drm_i915_private *dev_priv = dev->dev_private;
struct drm_mm_node *compressed_fb, *uninitialized_var(compressed_llb);
unsigned long cfb_base;
unsigned long ll_base = 0;
/* Just in case the BIOS is doing something questionable. */
intel_disable_fbc(dev);
compressed_fb = drm_mm_search_free(&dev_priv->mm.stolen, size, 4096, 0);
if (compressed_fb)
compressed_fb = drm_mm_get_block(compressed_fb, size, 4096);
if (!compressed_fb)
goto err;
cfb_base = dev_priv->mm.stolen_base + compressed_fb->start;
if (!cfb_base)
goto err_fb;
if (!(IS_GM45(dev) || HAS_PCH_SPLIT(dev))) {
compressed_llb = drm_mm_search_free(&dev_priv->mm.stolen,
4096, 4096, 0);
if (compressed_llb)
compressed_llb = drm_mm_get_block(compressed_llb,
4096, 4096);
if (!compressed_llb)
goto err_fb;
ll_base = dev_priv->mm.stolen_base + compressed_llb->start;
if (!ll_base)
goto err_llb;
}
dev_priv->cfb_size = size;
dev_priv->compressed_fb = compressed_fb;
if (HAS_PCH_SPLIT(dev))
I915_WRITE(ILK_DPFC_CB_BASE, compressed_fb->start);
else if (IS_GM45(dev)) {
I915_WRITE(DPFC_CB_BASE, compressed_fb->start);
} else {
I915_WRITE(FBC_CFB_BASE, cfb_base);
I915_WRITE(FBC_LL_BASE, ll_base);
dev_priv->compressed_llb = compressed_llb;
}
DRM_DEBUG_KMS("FBC base 0x%08lx, ll base 0x%08lx, size %dM\n",
(long)cfb_base, (long)ll_base, size >> 20);
return;
err_llb:
drm_mm_put_block(compressed_llb);
err_fb:
drm_mm_put_block(compressed_fb);
err:
dev_priv->no_fbc_reason = FBC_STOLEN_TOO_SMALL;
i915_warn_stolen(dev);
}
static void i915_cleanup_compression(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
drm_mm_put_block(dev_priv->compressed_fb);
if (dev_priv->compressed_llb)
drm_mm_put_block(dev_priv->compressed_llb);
}
void i915_gem_cleanup_stolen(struct drm_device *dev)
{
if (I915_HAS_FBC(dev) && i915_powersave)
i915_cleanup_compression(dev);
}
int i915_gem_init_stolen(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
unsigned long prealloc_size = dev_priv->mm.gtt->stolen_size;
dev_priv->mm.stolen_base = i915_stolen_to_physical(dev);
if (dev_priv->mm.stolen_base == 0)
return 0;
DRM_DEBUG_KMS("found %d bytes of stolen memory at %08lx\n",
dev_priv->mm.gtt->stolen_size, dev_priv->mm.stolen_base);
/* Basic memrange allocator for stolen space */
drm_mm_init(&dev_priv->mm.stolen, 0, prealloc_size);
/* Try to set up FBC with a reasonable compressed buffer size */
if (I915_HAS_FBC(dev) && i915_powersave) {
int cfb_size;
/* Leave 1M for line length buffer & misc. */
/* Try to get a 32M buffer... */
if (prealloc_size > (36*1024*1024))
cfb_size = 32*1024*1024;
else /* fall back to 7/8 of the stolen space */
cfb_size = prealloc_size * 7 / 8;
i915_setup_compression(dev, cfb_size);
}
return 0;
}
