* [RFC/PATCH v2 6/8] radeon: Switch to arch_phys_wc_add and add a missing ..._del
From: Andy Lutomirski @ 2013-05-09 19:46 UTC (permalink / raw)
To: linux-kernel, dri-devel, linux-fbdev
Cc: Daniel Vetter, Jerome Glisse, Alex Deucher, Dave Airlie,
Andy Lutomirski
In-Reply-To: <cover.1368128020.git.luto@amacapital.net>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
---
drivers/gpu/drm/radeon/radeon_object.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/radeon/radeon_object.c b/drivers/gpu/drm/radeon/radeon_object.c
index d3aface..15cd34b 100644
--- a/drivers/gpu/drm/radeon/radeon_object.c
+++ b/drivers/gpu/drm/radeon/radeon_object.c
@@ -321,8 +321,8 @@ void radeon_bo_force_delete(struct radeon_device *rdev)
int radeon_bo_init(struct radeon_device *rdev)
{
/* Add an MTRR for the VRAM */
- rdev->mc.vram_mtrr = mtrr_add(rdev->mc.aper_base, rdev->mc.aper_size,
- MTRR_TYPE_WRCOMB, 1);
+ rdev->mc.vram_mtrr = arch_phys_wc_add(rdev->mc.aper_base,
+ rdev->mc.aper_size);
DRM_INFO("Detected VRAM RAM=%lluM, BAR=%lluM\n",
rdev->mc.mc_vram_size >> 20,
(unsigned long long)rdev->mc.aper_size >> 20);
@@ -334,6 +334,7 @@ int radeon_bo_init(struct radeon_device *rdev)
void radeon_bo_fini(struct radeon_device *rdev)
{
radeon_ttm_fini(rdev);
+ arch_phys_wc_del(rdev->mc.vram_mtrr);
}
void radeon_bo_list_add_object(struct radeon_bo_list *lobj,
--
1.8.1.4
^ permalink raw reply related
* [RFC/PATCH v2 7/8] uvesafb: Clean up MTRR code
From: Andy Lutomirski @ 2013-05-09 19:46 UTC (permalink / raw)
To: linux-kernel, dri-devel, linux-fbdev
Cc: Daniel Vetter, Jerome Glisse, Alex Deucher, Dave Airlie,
Andy Lutomirski, Michal Januszewski
In-Reply-To: <cover.1368128020.git.luto@amacapital.net>
The old code allowed very strange memory types. Now it works like
all the other video drivers: ioremap_wc is used unconditionally,
and MTRRs are set if PAT is unavailable (unless MTRR is disabled
by a module parameter).
UC, WB, and WT support is gone. If there are MTRR conflicts that prevent
addition of a WC MTRR, adding a non-conflicting MTRR is pointless; it's
better to just turn off MTRR support entirely.
As an added bonus, any MTRR added is freed on unload.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
---
Documentation/fb/uvesafb.txt | 16 ++++------
drivers/video/uvesafb.c | 70 +++++++++++---------------------------------
include/video/uvesafb.h | 1 +
3 files changed, 23 insertions(+), 64 deletions(-)
diff --git a/Documentation/fb/uvesafb.txt b/Documentation/fb/uvesafb.txt
index eefdd91..f6362d8 100644
--- a/Documentation/fb/uvesafb.txt
+++ b/Documentation/fb/uvesafb.txt
@@ -81,17 +81,11 @@ pmipal Use the protected mode interface for palette changes.
mtrr:n Setup memory type range registers for the framebuffer
where n:
- 0 - disabled (equivalent to nomtrr) (default)
- 1 - uncachable
- 2 - write-back
- 3 - write-combining
- 4 - write-through
-
- If you see the following in dmesg, choose the type that matches
- the old one. In this example, use "mtrr:2".
-...
-mtrr: type mismatch for e0000000,8000000 old: write-back new: write-combining
-...
+ 0 - disabled (equivalent to nomtrr)
+ 3 - write-combining (default)
+
+ Values other than 0 and 3 will result in a warning and will be
+ treated just like 3.
nomtrr Do not use memory type range registers.
diff --git a/drivers/video/uvesafb.c b/drivers/video/uvesafb.c
index d428445..8701f96 100644
--- a/drivers/video/uvesafb.c
+++ b/drivers/video/uvesafb.c
@@ -24,9 +24,6 @@
#ifdef CONFIG_X86
#include <video/vga.h>
#endif
-#ifdef CONFIG_MTRR
-#include <asm/mtrr.h>
-#endif
#include "edid.h"
static struct cb_id uvesafb_cn_id = {
@@ -1540,67 +1537,30 @@ static void uvesafb_init_info(struct fb_info *info, struct vbe_mode_ib *mode)
static void uvesafb_init_mtrr(struct fb_info *info)
{
-#ifdef CONFIG_MTRR
+ struct uvesafb_par *par = info->par;
+
if (mtrr && !(info->fix.smem_start & (PAGE_SIZE - 1))) {
int temp_size = info->fix.smem_len;
- unsigned int type = 0;
- switch (mtrr) {
- case 1:
- type = MTRR_TYPE_UNCACHABLE;
- break;
- case 2:
- type = MTRR_TYPE_WRBACK;
- break;
- case 3:
- type = MTRR_TYPE_WRCOMB;
- break;
- case 4:
- type = MTRR_TYPE_WRTHROUGH;
- break;
- default:
- type = 0;
- break;
- }
+ int rc;
- if (type) {
- int rc;
+ /* Find the largest power-of-two */
+ temp_size = roundup_pow_of_two(temp_size);
- /* Find the largest power-of-two */
- temp_size = roundup_pow_of_two(temp_size);
+ /* Try and find a power of two to add */
+ do {
+ rc = arch_phys_wc_add(info->fix.smem_start, temp_size);
+ temp_size >>= 1;
+ } while (temp_size >= PAGE_SIZE && rc = -EINVAL);
- /* Try and find a power of two to add */
- do {
- rc = mtrr_add(info->fix.smem_start,
- temp_size, type, 1);
- temp_size >>= 1;
- } while (temp_size >= PAGE_SIZE && rc = -EINVAL);
- }
+ if (rc >= 0)
+ par->mtrr_handle = rc;
}
-#endif /* CONFIG_MTRR */
}
static void uvesafb_ioremap(struct fb_info *info)
{
-#ifdef CONFIG_X86
- switch (mtrr) {
- case 1: /* uncachable */
- info->screen_base = ioremap_nocache(info->fix.smem_start, info->fix.smem_len);
- break;
- case 2: /* write-back */
- info->screen_base = ioremap_cache(info->fix.smem_start, info->fix.smem_len);
- break;
- case 3: /* write-combining */
- info->screen_base = ioremap_wc(info->fix.smem_start, info->fix.smem_len);
- break;
- case 4: /* write-through */
- default:
- info->screen_base = ioremap(info->fix.smem_start, info->fix.smem_len);
- break;
- }
-#else
- info->screen_base = ioremap(info->fix.smem_start, info->fix.smem_len);
-#endif /* CONFIG_X86 */
+ info->screen_base = ioremap_wc(info->fix.smem_start, info->fix.smem_len);
}
static ssize_t uvesafb_show_vbe_ver(struct device *dev,
@@ -1851,6 +1811,7 @@ static int uvesafb_remove(struct platform_device *dev)
unregister_framebuffer(info);
release_region(0x3c0, 32);
iounmap(info->screen_base);
+ arch_phys_wc_del(par->mtrr_handle);
release_mem_region(info->fix.smem_start, info->fix.smem_len);
fb_destroy_modedb(info->monspecs.modedb);
fb_dealloc_cmap(&info->cmap);
@@ -1930,6 +1891,9 @@ static int uvesafb_setup(char *options)
}
}
+ if (mtrr != 3 && mtrr != 1)
+ pr_warn("uvesafb: mtrr should be set to 0 or 3; %d is unsupported", mtrr);
+
return 0;
}
#endif /* !MODULE */
diff --git a/include/video/uvesafb.h b/include/video/uvesafb.h
index 1a91850..30f5362 100644
--- a/include/video/uvesafb.h
+++ b/include/video/uvesafb.h
@@ -134,6 +134,7 @@ struct uvesafb_par {
int mode_idx;
struct vbe_crtc_ib crtc;
+ int mtrr_handle;
};
#endif /* _UVESAFB_H */
--
1.8.1.4
^ permalink raw reply related
* [RFC/PATCH v2 8/8] drm: Remove mtrr_add and mtrr_del fallback hack for non-MTRR systems
From: Andy Lutomirski @ 2013-05-09 19:46 UTC (permalink / raw)
To: linux-kernel, dri-devel, linux-fbdev
Cc: Daniel Vetter, Jerome Glisse, Alex Deucher, Dave Airlie,
Andy Lutomirski
In-Reply-To: <cover.1368128020.git.luto@amacapital.net>
There are no users left in drivers/gpu.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
---
This is new in v2. The code I'm deleting is kind of gross.
include/drm/drmP.h | 5 +----
include/drm/drm_os_linux.h | 16 ----------------
2 files changed, 1 insertion(+), 20 deletions(-)
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index 3e6cfa0..7a9fef5 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -55,16 +55,13 @@
#include <linux/mm.h>
#include <linux/cdev.h>
#include <linux/mutex.h>
+#include <linux/io.h>
#include <linux/slab.h>
#if defined(__alpha__) || defined(__powerpc__)
#include <asm/pgtable.h> /* For pte_wrprotect */
#endif
-#include <asm/io.h>
#include <asm/mman.h>
#include <asm/uaccess.h>
-#ifdef CONFIG_MTRR
-#include <asm/mtrr.h>
-#endif
#if defined(CONFIG_AGP) || defined(CONFIG_AGP_MODULE)
#include <linux/types.h>
#include <linux/agp_backend.h>
diff --git a/include/drm/drm_os_linux.h b/include/drm/drm_os_linux.h
index 3933691..35c7c2b 100644
--- a/include/drm/drm_os_linux.h
+++ b/include/drm/drm_os_linux.h
@@ -65,22 +65,6 @@ struct no_agp_kern {
#define DRM_AGP_KERN struct no_agp_kern
#endif
-#if !(__OS_HAS_MTRR)
-static __inline__ int mtrr_add(unsigned long base, unsigned long size,
- unsigned int type, char increment)
-{
- return -ENODEV;
-}
-
-static __inline__ int mtrr_del(int reg, unsigned long base, unsigned long size)
-{
- return -ENODEV;
-}
-
-#define MTRR_TYPE_WRCOMB 1
-
-#endif
-
/** Other copying of data to kernel space */
#define DRM_COPY_FROM_USER(arg1, arg2, arg3) \
copy_from_user(arg1, arg2, arg3)
--
1.8.1.4
^ permalink raw reply related
* [PATCH 01/12] fbdev: FB_GOLDFISH should depend on HAS_DMA
From: Geert Uytterhoeven @ 2013-05-09 21:04 UTC (permalink / raw)
To: linux-kernel; +Cc: Geert Uytterhoeven, Florian Tobias Schandinat, linux-fbdev
If NO_DMA=y:
drivers/built-in.o: In function `goldfish_fb_remove':
drivers/video/goldfishfb.c:301: undefined reference to `dma_free_coherent'
drivers/built-in.o: In function `goldfish_fb_probe':
drivers/video/goldfishfb.c:247: undefined reference to `dma_alloc_coherent'
drivers/video/goldfishfb.c:280: undefined reference to `dma_free_coherent'
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: linux-fbdev@vger.kernel.org
---
drivers/video/Kconfig | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index 9669c9c..da01cec 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -2199,7 +2199,7 @@ config FB_XILINX
config FB_GOLDFISH
tristate "Goldfish Framebuffer"
- depends on FB
+ depends on FB && HAS_DMA
select FB_CFB_FILLRECT
select FB_CFB_COPYAREA
select FB_CFB_IMAGEBLIT
--
1.7.0.4
^ permalink raw reply related
* Re: [RFC/PATCH v2 0/8] Clean up write-combining MTRR addition
From: Jerome Glisse @ 2013-05-09 23:44 UTC (permalink / raw)
To: Andy Lutomirski; +Cc: linux-fbdev, Daniel Vetter, linux-kernel, dri-devel
In-Reply-To: <cover.1368128020.git.luto@amacapital.net>
On Thu, May 9, 2013 at 3:46 PM, Andy Lutomirski <luto@amacapital.net> wrote:
> A fair number of drivers (mostly graphics) add write-combining MTRRs.
> Most ignore errors and most add the MTRR even on PAT systems which don't
> need to use MTRRs.
This comment is wrong, as i said we need MTRR on PAT system for VRAM.
Cheers,
Jerome
> This series adds new functions arch_phys_wc_{add,del} that, on PAT-less
> x86 systems with MTRRs, add MTRRs and report errors, and that do nothing
> otherwise. (Other architectures, if any, with a similar mechanism could
> implement them.)
>
> I've only tested the radeon driver, since I don't have test hardware
> easily available for the other drivers.
>
> Benefits include:
> - Simpler code
> - No more complaints about MTRR conflict warnings on PAT systems
> - Eventual unexporting of the MTRR API?
>
> This series eliminates about half of the mtrr_add calls in drivers/.
>
> Changes from v1:
> - Helpers renamed
> - Lots of bugs fixed
>
> The series is also at:
> https://git.kernel.org/cgit/linux/kernel/git/luto/linux.git/log/?h=mtrr_cleanup/rfc_v2
>
> Andy Lutomirski (8):
> Add arch_phys_wc_{add,del} to manipulate WC MTRRs if needed
> drm (ast,cirrus,mgag200,nouveau,savage,vmwgfx): Remove
> drm_mtrr_{add,del}
> drm: Update drm_addmap and drm_mmap to use PAT WC instead of MTRRs
> drm,agpgart: Use pgprot_writecombine for AGP maps and make the MTRR
> optional
> i915: Use arch_phys_wc_{add,del}
> radeon: Switch to arch_phys_wc_add and add a missing ..._del
> uvesafb: Clean up MTRR code
> drm: Remove mtrr_add and mtrr_del fallback hack for non-MTRR systems
>
> Documentation/fb/uvesafb.txt | 16 +++-----
> arch/x86/include/asm/io.h | 7 ++++
> arch/x86/include/asm/mtrr.h | 5 ++-
> arch/x86/kernel/cpu/mtrr/main.c | 48 +++++++++++++++++++++++
> drivers/char/agp/frontend.c | 8 ++--
> drivers/gpu/drm/ast/ast_ttm.c | 13 ++-----
> drivers/gpu/drm/cirrus/cirrus_ttm.c | 15 ++------
> drivers/gpu/drm/drm_bufs.c | 17 +++++----
> drivers/gpu/drm/drm_pci.c | 8 ++--
> drivers/gpu/drm/drm_stub.c | 10 +----
> drivers/gpu/drm/drm_vm.c | 22 +++++------
> drivers/gpu/drm/i915/i915_dma.c | 44 +++------------------
> drivers/gpu/drm/mgag200/mgag200_ttm.c | 14 ++-----
> drivers/gpu/drm/nouveau/nouveau_ttm.c | 13 ++-----
> drivers/gpu/drm/radeon/radeon_object.c | 5 ++-
> drivers/gpu/drm/savage/savage_bci.c | 43 ++++++++-------------
> drivers/gpu/drm/savage/savage_drv.h | 5 +--
> drivers/gpu/drm/vmwgfx/vmwgfx_drv.c | 10 ++---
> drivers/video/uvesafb.c | 70 +++++++++-------------------------
> include/drm/drmP.h | 34 +----------------
> include/drm/drm_os_linux.h | 16 --------
> include/linux/io.h | 25 ++++++++++++
> include/video/uvesafb.h | 1 +
> 23 files changed, 181 insertions(+), 268 deletions(-)
>
> --
> 1.8.1.4
>
^ permalink raw reply
* Re: [RFC/PATCH v2 0/8] Clean up write-combining MTRR addition
From: Andy Lutomirski @ 2013-05-10 1:21 UTC (permalink / raw)
To: Jerome Glisse
Cc: linux-kernel, dri-devel, linux-fbdev, Daniel Vetter, Alex Deucher,
Dave Airlie
In-Reply-To: <CAH3drwa_ypKKqZ8eayeR4fA4Ounj55R3R9y0_b5crp99YMFQ=w@mail.gmail.com>
On Thu, May 9, 2013 at 4:44 PM, Jerome Glisse <j.glisse@gmail.com> wrote:
> On Thu, May 9, 2013 at 3:46 PM, Andy Lutomirski <luto@amacapital.net> wrote:
>> A fair number of drivers (mostly graphics) add write-combining MTRRs.
>> Most ignore errors and most add the MTRR even on PAT systems which don't
>> need to use MTRRs.
>
> This comment is wrong, as i said we need MTRR on PAT system for VRAM.
I didn't follow it last time.
- If userspace is setting an MTRR directly, then it will work exactly
as before -- this patch has no effect on the userspace MTRR APIs.
- If userspace uses the drm map interface with DRM_FRAME_BUFFER or
DRM_WRITE_COMBINING, there won't be an MTRR but the range will still
be WC.
- If userspace uses GEM or TTM, then everything should still use WC
(TTM has explicit handling for this, which I presume is correct, and
i915, the major GEM user, already doesn't set an MTRR).
- If userspace does not map the range, then either the kernel driver
is buggy or it doesn't matter because there's no map.
Is there a case I've missed?
--Andy
^ permalink raw reply
* [RFC 32/42] drivers/video: don't check resource with devm_ioremap_resource
From: Wolfram Sang @ 2013-05-10 8:17 UTC (permalink / raw)
To: linux-kernel; +Cc: Wolfram Sang, Florian Tobias Schandinat, linux-fbdev
In-Reply-To: <1368173847-5661-1-git-send-email-wsa@the-dreams.de>
devm_ioremap_resource does sanity checks on the given resource. No need to
duplicate this in the driver.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
---
drivers/video/mxsfb.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)
diff --git a/drivers/video/mxsfb.c b/drivers/video/mxsfb.c
index 1b2c26d..3dc3265 100644
--- a/drivers/video/mxsfb.c
+++ b/drivers/video/mxsfb.c
@@ -883,12 +883,6 @@ static int mxsfb_probe(struct platform_device *pdev)
if (of_id)
pdev->id_entry = of_id->data;
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!res) {
- dev_err(&pdev->dev, "Cannot get memory IO resource\n");
- return -ENODEV;
- }
-
fb_info = framebuffer_alloc(sizeof(struct mxsfb_info), &pdev->dev);
if (!fb_info) {
dev_err(&pdev->dev, "Failed to allocate fbdev\n");
@@ -897,6 +891,7 @@ static int mxsfb_probe(struct platform_device *pdev)
host = to_imxfb_host(fb_info);
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
host->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(host->base)) {
dev_err(&pdev->dev, "ioremap failed\n");
--
1.7.10.4
^ permalink raw reply related
* [RFC 33/42] drivers/video/omap2: don't check resource with devm_ioremap_resource
From: Wolfram Sang @ 2013-05-10 8:17 UTC (permalink / raw)
To: linux-kernel
Cc: Wolfram Sang, Tomi Valkeinen, Florian Tobias Schandinat,
linux-omap, linux-fbdev
In-Reply-To: <1368173847-5661-1-git-send-email-wsa@the-dreams.de>
devm_ioremap_resource does sanity checks on the given resource. No need to
duplicate this in the driver.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
---
drivers/video/omap2/vrfb.c | 5 -----
1 file changed, 5 deletions(-)
diff --git a/drivers/video/omap2/vrfb.c b/drivers/video/omap2/vrfb.c
index 5261229..f346b02 100644
--- a/drivers/video/omap2/vrfb.c
+++ b/drivers/video/omap2/vrfb.c
@@ -353,11 +353,6 @@ static int __init vrfb_probe(struct platform_device *pdev)
/* first resource is the register res, the rest are vrfb contexts */
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!mem) {
- dev_err(&pdev->dev, "can't get vrfb base address\n");
- return -EINVAL;
- }
-
vrfb_base = devm_ioremap_resource(&pdev->dev, mem);
if (IS_ERR(vrfb_base))
return PTR_ERR(vrfb_base);
--
1.7.10.4
^ permalink raw reply related
* [RFC 34/42] drivers/video/omap2/dss: don't check resource with devm_ioremap_resource
From: Wolfram Sang @ 2013-05-10 8:17 UTC (permalink / raw)
To: linux-kernel
Cc: Wolfram Sang, Tomi Valkeinen, Florian Tobias Schandinat,
linux-omap, linux-fbdev
In-Reply-To: <1368173847-5661-1-git-send-email-wsa@the-dreams.de>
devm_ioremap_resource does sanity checks on the given resource. No need to
duplicate this in the driver.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
---
drivers/video/omap2/dss/hdmi.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)
diff --git a/drivers/video/omap2/dss/hdmi.c b/drivers/video/omap2/dss/hdmi.c
index 17f4d55..7bc6762 100644
--- a/drivers/video/omap2/dss/hdmi.c
+++ b/drivers/video/omap2/dss/hdmi.c
@@ -1064,13 +1064,8 @@ static int omapdss_hdmihw_probe(struct platform_device *pdev)
mutex_init(&hdmi.lock);
mutex_init(&hdmi.ip_data.lock);
- res = platform_get_resource(hdmi.pdev, IORESOURCE_MEM, 0);
- if (!res) {
- DSSERR("can't get IORESOURCE_MEM HDMI\n");
- return -EINVAL;
- }
-
/* Base address taken from platform */
+ res = platform_get_resource(hdmi.pdev, IORESOURCE_MEM, 0);
hdmi.ip_data.base_wp = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(hdmi.ip_data.base_wp))
return PTR_ERR(hdmi.ip_data.base_wp);
--
1.7.10.4
^ permalink raw reply related
* Re: [RFC/PATCH v2 1/8] Add arch_phys_wc_{add,del} to manipulate WC MTRRs if needed
From: Daniel Vetter @ 2013-05-10 9:19 UTC (permalink / raw)
To: Andy Lutomirski
Cc: linux-kernel, dri-devel, linux-fbdev, Daniel Vetter,
Jerome Glisse, Alex Deucher, Dave Airlie
In-Reply-To: <97346b603822ffd8ab446316fc08fbf7686c9d50.1368128020.git.luto@amacapital.net>
On Thu, May 09, 2013 at 12:46:20PM -0700, Andy Lutomirski wrote:
> Several drivers currently use mtrr_add through various #ifdef guards
> and/or drm wrappers. The vast majority of them want to add WC MTRRs
> on x86 systems and don't actually need the MTRR if PAT (i.e.
> ioremap_wc, etc) are working.
>
> arch_phys_wc_add and arch_phys_wc_del are new functions, available
> on all architectures and configurations, that add WC MTRRs on x86 if
> needed (and handle errors) and do nothing at all otherwise. They're
> also easier to use than mtrr_add and mtrr_del, so the call sites can
> be simplified.
>
> As an added benefit, this will avoid wasting MTRRs and possibly
> warning pointlessly on PAT-supporting systems.
>
> Signed-off-by: Andy Lutomirski <luto@amacapital.net>
> ---
> arch/x86/include/asm/io.h | 7 ++++++
> arch/x86/include/asm/mtrr.h | 5 ++++-
> arch/x86/kernel/cpu/mtrr/main.c | 48 +++++++++++++++++++++++++++++++++++++++++
> include/linux/io.h | 25 +++++++++++++++++++++
> 4 files changed, 84 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
> index d8e8eef..34f69cb 100644
> --- a/arch/x86/include/asm/io.h
> +++ b/arch/x86/include/asm/io.h
> @@ -345,4 +345,11 @@ extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
>
> #define IO_SPACE_LIMIT 0xffff
>
> +#ifdef CONFIG_MTRR
> +extern int __must_check arch_phys_wc_add(unsigned long base,
> + unsigned long size);
> +extern void arch_phys_wc_del(int handle);
> +#define arch_phys_wc_add arch_phys_wc_add
> +#endif
> +
> #endif /* _ASM_X86_IO_H */
> diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h
> index e235582..10d0fba 100644
> --- a/arch/x86/include/asm/mtrr.h
> +++ b/arch/x86/include/asm/mtrr.h
> @@ -26,7 +26,10 @@
> #include <uapi/asm/mtrr.h>
>
>
> -/* The following functions are for use by other drivers */
> +/*
> + * The following functions are for use by other drivers that cannot use
> + * arch_phys_wc_add and arch_phys_wc_del.
> + */
> # ifdef CONFIG_MTRR
> extern u8 mtrr_type_lookup(u64 addr, u64 end);
> extern void mtrr_save_fixed_ranges(void *);
> diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c
> index 726bf96..23bd49a 100644
> --- a/arch/x86/kernel/cpu/mtrr/main.c
> +++ b/arch/x86/kernel/cpu/mtrr/main.c
> @@ -51,6 +51,7 @@
> #include <asm/e820.h>
> #include <asm/mtrr.h>
> #include <asm/msr.h>
> +#include <asm/pat.h>
>
> #include "mtrr.h"
>
> @@ -524,6 +525,53 @@ int mtrr_del(int reg, unsigned long base, unsigned long size)
> }
> EXPORT_SYMBOL(mtrr_del);
>
> +/**
> + * arch_phys_wc_add - add a WC MTRR and handle errors if PAT is unavailable
> + * @base: Physical base address
> + * @size: Size of region
> + *
> + * If PAT is available, this does nothing. If PAT is unavailable, it
> + * attempts to add a WC MTRR covering size bytes starting at base and
> + * logs an error if this fails.
> + *
> + * Drivers must store the return value to pass to mtrr_del_wc_if_needed,
> + * but drivers should not try to interpret that return value.
> + */
> +int arch_phys_wc_add(unsigned long base, unsigned long size)
> +{
> + int ret;
> +
> + if (pat_enabled)
> + return 0; /* Success! (We don't need to do anything.) */
Shouldn't we #define a big number for this case since mtrr_add returns
0-based mtrr indices? Rather unlikely that the very first mtrr is unused I
know, but still feels like a cleaner interface. And we don't need to leak
that #define out at all to users of this interface.
-Daniel
> +
> + ret = mtrr_add(base, size, MTRR_TYPE_WRCOMB, true);
> + if (ret < 0) {
> + pr_warn("Failed to add WC MTRR for [%p-%p]; performance may suffer.",
> + (void *)base, (void *)(base + size - 1));
> + return ret;
> + }
> + return ret + 1000;
> +}
> +EXPORT_SYMBOL(arch_phys_wc_add);
> +
> +/*
> + * arch_phys_wc_del - undoes arch_phys_wc_add
> + * @handle: Return value from arch_phys_wc_add
> + *
> + * This cleans up after mtrr_add_wc_if_needed.
> + *
> + * The API guarantees that mtrr_del_wc_if_needed(error code) and
> + * mtrr_del_wc_if_needed(0) do nothing.
> + */
> +extern void arch_phys_wc_del(int handle)
> +{
> + if (handle >= 1) {
> + WARN_ON(handle < 1000);
> + mtrr_del(handle - 1000, 0, 0);
> + }
> +}
> +EXPORT_SYMBOL(arch_phys_wc_del);
> +
> /*
> * HACK ALERT!
> * These should be called implicitly, but we can't yet until all the initcall
> diff --git a/include/linux/io.h b/include/linux/io.h
> index 069e407..f4f42fa 100644
> --- a/include/linux/io.h
> +++ b/include/linux/io.h
> @@ -76,4 +76,29 @@ void devm_ioremap_release(struct device *dev, void *res);
> #define arch_has_dev_port() (1)
> #endif
>
> +/*
> + * Some systems (x86 without PAT) have a somewhat reliable way to mark a
> + * physical address range such that uncached mappings will actually
> + * end up write-combining. This facility should be used in conjunction
> + * with pgprot_writecombine, ioremap-wc, or set_memory_wc, since it has
> + * no effect if the per-page mechanisms are functional.
> + * (On x86 without PAT, these functions manipulate MTRRs.)
> + *
> + * arch_phys_del_wc(0) or arch_phys_del_wc(any error code) is guaranteed
> + * to have no effect.
> + */
> +#ifndef arch_phys_wc_add
> +static inline int __must_check arch_phys_wc_add(unsigned long base,
> + unsigned long size)
> +{
> + return 0; /* It worked (i.e. did nothing). */
> +}
> +
> +static inline void arch_phys_wc_del(int handle)
> +{
> +}
> +
> +#define arch_phys_wc_add arch_phys_wc_add
> +#endif
> +
> #endif /* _LINUX_IO_H */
> --
> 1.8.1.4
>
--
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch
^ permalink raw reply
* Re: [RFC/PATCH v2 5/8] i915: Use arch_phys_wc_{add,del}
From: Daniel Vetter @ 2013-05-10 9:36 UTC (permalink / raw)
To: Andy Lutomirski
Cc: linux-kernel, dri-devel, linux-fbdev, Daniel Vetter,
Jerome Glisse, Alex Deucher, Dave Airlie
In-Reply-To: <2d9af02b508eaf182c72b6e60a63070de265a759.1368128020.git.luto@amacapital.net>
On Thu, May 09, 2013 at 12:46:24PM -0700, Andy Lutomirski wrote:
> i915 open-coded logic that was essentially equivalent to the new API.
>
> Signed-off-by: Andy Lutomirski <luto@amacapital.net>
> ---
>
> Changes from v1: More cleanup
>
> drivers/gpu/drm/i915/i915_dma.c | 44 ++++++-----------------------------------
> 1 file changed, 6 insertions(+), 38 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
> index 4fa6beb..cfdfb45 100644
> --- a/drivers/gpu/drm/i915/i915_dma.c
> +++ b/drivers/gpu/drm/i915/i915_dma.c
> @@ -42,7 +42,6 @@
> #include <linux/vga_switcheroo.h>
> #include <linux/slab.h>
> #include <acpi/video.h>
> -#include <asm/pat.h>
>
> #define LP_RING(d) (&((struct drm_i915_private *)(d))->ring[RCS])
>
> @@ -1393,29 +1392,6 @@ void i915_master_destroy(struct drm_device *dev, struct drm_master *master)
> master->driver_priv = NULL;
> }
>
> -static void
> -i915_mtrr_setup(struct drm_i915_private *dev_priv, unsigned long base,
> - unsigned long size)
> -{
> - dev_priv->mm.gtt_mtrr = -1;
> -
> -#if defined(CONFIG_X86_PAT)
> - if (cpu_has_pat)
> - return;
> -#endif
> -
> - /* Set up a WC MTRR for non-PAT systems. This is more common than
> - * one would think, because the kernel disables PAT on first
> - * generation Core chips because WC PAT gets overridden by a UC
> - * MTRR if present. Even if a UC MTRR isn't present.
> - */
> - dev_priv->mm.gtt_mtrr = mtrr_add(base, size, MTRR_TYPE_WRCOMB, 1);
> - if (dev_priv->mm.gtt_mtrr < 0) {
> - DRM_INFO("MTRR allocation failed. Graphics "
> - "performance may suffer.\n");
> - }
> -}
> -
> static void i915_kick_out_firmware_fb(struct drm_i915_private *dev_priv)
> {
> struct apertures_struct *ap;
> @@ -1552,8 +1528,8 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
> goto out_rmmap;
> }
>
> - i915_mtrr_setup(dev_priv, dev_priv->gtt.mappable_base,
> - aperture_size);
> + dev_priv->mm.gtt_mtrr = arch_phys_wc_add(dev_priv->gtt.mappable_base,
> + aperture_size);
>
> /* The i915 workqueue is primarily used for batched retirement of
> * requests (and thus managing bo) once the task has been completed
> @@ -1656,12 +1632,8 @@ out_gem_unload:
> intel_teardown_mchbar(dev);
> destroy_workqueue(dev_priv->wq);
> out_mtrrfree:
> - if (dev_priv->mm.gtt_mtrr >= 0) {
> - mtrr_del(dev_priv->mm.gtt_mtrr,
> - dev_priv->gtt.mappable_base,
> - aperture_size);
> - dev_priv->mm.gtt_mtrr = -1;
> - }
> + arch_phys_wc_del(dev_priv->mm.gtt_mtrr);
> + dev_priv->mm.gtt_mtrr = 0;
I think you can drop this gtt_mtrr = 0 asignment (and the one below) since
the driver will be unloaded anyway and no longer care. And with my
bikeshed on the first 1 patch it'd be wrong, too.
-Daniel
> io_mapping_free(dev_priv->gtt.mappable);
> out_rmmap:
> pci_iounmap(dev->pdev, dev_priv->regs);
> @@ -1697,12 +1669,8 @@ int i915_driver_unload(struct drm_device *dev)
> cancel_delayed_work_sync(&dev_priv->mm.retire_work);
>
> io_mapping_free(dev_priv->gtt.mappable);
> - if (dev_priv->mm.gtt_mtrr >= 0) {
> - mtrr_del(dev_priv->mm.gtt_mtrr,
> - dev_priv->gtt.mappable_base,
> - dev_priv->gtt.mappable_end);
> - dev_priv->mm.gtt_mtrr = -1;
> - }
> + arch_phys_wc_del(dev_priv->mm.gtt_mtrr);
> + dev_priv->mm.gtt_mtrr = 0;
>
> acpi_video_unregister();
>
> --
> 1.8.1.4
>
--
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch
^ permalink raw reply
* Re: [RFC/PATCH v2 0/8] Clean up write-combining MTRR addition
From: Daniel Vetter @ 2013-05-10 9:42 UTC (permalink / raw)
To: Andy Lutomirski
Cc: linux-kernel, dri-devel, linux-fbdev, Daniel Vetter,
Jerome Glisse, Alex Deucher, Dave Airlie
In-Reply-To: <cover.1368128020.git.luto@amacapital.net>
On Thu, May 09, 2013 at 12:46:19PM -0700, Andy Lutomirski wrote:
> A fair number of drivers (mostly graphics) add write-combining MTRRs.
> Most ignore errors and most add the MTRR even on PAT systems which don't
> need to use MTRRs.
>
> This series adds new functions arch_phys_wc_{add,del} that, on PAT-less
> x86 systems with MTRRs, add MTRRs and report errors, and that do nothing
> otherwise. (Other architectures, if any, with a similar mechanism could
> implement them.)
>
> I've only tested the radeon driver, since I don't have test hardware
> easily available for the other drivers.
>
> Benefits include:
> - Simpler code
> - No more complaints about MTRR conflict warnings on PAT systems
> - Eventual unexporting of the MTRR API?
>
> This series eliminates about half of the mtrr_add calls in drivers/.
>
> Changes from v1:
> - Helpers renamed
> - Lots of bugs fixed
>
> The series is also at:
> https://git.kernel.org/cgit/linux/kernel/git/luto/linux.git/log/?h=mtrr_cleanup/rfc_v2
>
> Andy Lutomirski (8):
> Add arch_phys_wc_{add,del} to manipulate WC MTRRs if needed
> drm (ast,cirrus,mgag200,nouveau,savage,vmwgfx): Remove
> drm_mtrr_{add,del}
> drm: Update drm_addmap and drm_mmap to use PAT WC instead of MTRRs
> drm,agpgart: Use pgprot_writecombine for AGP maps and make the MTRR
> optional
> i915: Use arch_phys_wc_{add,del}
> radeon: Switch to arch_phys_wc_add and add a missing ..._del
> uvesafb: Clean up MTRR code
> drm: Remove mtrr_add and mtrr_del fallback hack for non-MTRR systems
With my two comments addressed, the entire series is
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
My knowledge for the userspace driver created drm maps in drm_vm.c is a
bit shoddy. Otoh most of the code I've seen using that is _horribly_
broken (as in userspace creates a register map that the kernel uses, with
no refcounting at all). Your changes look correct though, so I think this
is about as good as it gets.
Yours, Daniel
>
> Documentation/fb/uvesafb.txt | 16 +++-----
> arch/x86/include/asm/io.h | 7 ++++
> arch/x86/include/asm/mtrr.h | 5 ++-
> arch/x86/kernel/cpu/mtrr/main.c | 48 +++++++++++++++++++++++
> drivers/char/agp/frontend.c | 8 ++--
> drivers/gpu/drm/ast/ast_ttm.c | 13 ++-----
> drivers/gpu/drm/cirrus/cirrus_ttm.c | 15 ++------
> drivers/gpu/drm/drm_bufs.c | 17 +++++----
> drivers/gpu/drm/drm_pci.c | 8 ++--
> drivers/gpu/drm/drm_stub.c | 10 +----
> drivers/gpu/drm/drm_vm.c | 22 +++++------
> drivers/gpu/drm/i915/i915_dma.c | 44 +++------------------
> drivers/gpu/drm/mgag200/mgag200_ttm.c | 14 ++-----
> drivers/gpu/drm/nouveau/nouveau_ttm.c | 13 ++-----
> drivers/gpu/drm/radeon/radeon_object.c | 5 ++-
> drivers/gpu/drm/savage/savage_bci.c | 43 ++++++++-------------
> drivers/gpu/drm/savage/savage_drv.h | 5 +--
> drivers/gpu/drm/vmwgfx/vmwgfx_drv.c | 10 ++---
> drivers/video/uvesafb.c | 70 +++++++++-------------------------
> include/drm/drmP.h | 34 +----------------
> include/drm/drm_os_linux.h | 16 --------
> include/linux/io.h | 25 ++++++++++++
> include/video/uvesafb.h | 1 +
> 23 files changed, 181 insertions(+), 268 deletions(-)
>
> --
> 1.8.1.4
>
--
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch
^ permalink raw reply
* [PATCH 1/1] video: smscufx: Use NULL instead of 0
From: Sachin Kamat @ 2013-05-10 11:47 UTC (permalink / raw)
To: linux-fbdev
'info' is a pointer. Use NULL instead of 0.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
---
drivers/video/smscufx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/video/smscufx.c b/drivers/video/smscufx.c
index b2b33fc..e188ada 100644
--- a/drivers/video/smscufx.c
+++ b/drivers/video/smscufx.c
@@ -1622,7 +1622,7 @@ static int ufx_usb_probe(struct usb_interface *interface,
{
struct usb_device *usbdev;
struct ufx_data *dev;
- struct fb_info *info = 0;
+ struct fb_info *info = NULL;
int retval = -ENOMEM;
u32 id_rev, fpga_rev;
--
1.7.9.5
^ permalink raw reply related
* [PATCH 1/1] video: udlfb: Use NULL instead of 0
From: Sachin Kamat @ 2013-05-10 11:50 UTC (permalink / raw)
To: linux-fbdev
'dev' is a pointer. Use NULL instead of 0.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
---
drivers/video/udlfb.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/video/udlfb.c b/drivers/video/udlfb.c
index ec03e72..04eadc6 100644
--- a/drivers/video/udlfb.c
+++ b/drivers/video/udlfb.c
@@ -1588,7 +1588,7 @@ static int dlfb_usb_probe(struct usb_interface *interface,
const struct usb_device_id *id)
{
struct usb_device *usbdev;
- struct dlfb_data *dev = 0;
+ struct dlfb_data *dev = NULL;
int retval = -ENOMEM;
/* usb initialization */
--
1.7.9.5
^ permalink raw reply related
* Re: [PATCH 1/1] video: udlfb: Use NULL instead of 0
From: Sachin Kamat @ 2013-05-10 11:55 UTC (permalink / raw)
To: linux-fbdev
In-Reply-To: <1368185906-13351-1-git-send-email-sachin.kamat@linaro.org>
On 10 May 2013 17:08, Sachin Kamat <sachin.kamat@linaro.org> wrote:
> 'dev' is a pointer. Use NULL instead of 0.
>
> Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
> ---
> drivers/video/udlfb.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/video/udlfb.c b/drivers/video/udlfb.c
> index ec03e72..04eadc6 100644
> --- a/drivers/video/udlfb.c
> +++ b/drivers/video/udlfb.c
> @@ -1588,7 +1588,7 @@ static int dlfb_usb_probe(struct usb_interface *interface,
> const struct usb_device_id *id)
> {
> struct usb_device *usbdev;
> - struct dlfb_data *dev = 0;
> + struct dlfb_data *dev = NULL;
> int retval = -ENOMEM;
>
> /* usb initialization */
> --
> 1.7.9.5
>
Please ignore this patch. Re-sending with few more fixes.
--
With warm regards,
Sachin
^ permalink raw reply
* [PATCH 1/2] video: udlfb: Use NULL instead of 0
From: Sachin Kamat @ 2013-05-10 11:58 UTC (permalink / raw)
To: linux-fbdev
Pointer variables should be initialized with NULL instead of 0.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
---
drivers/video/udlfb.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/video/udlfb.c b/drivers/video/udlfb.c
index ec03e72..20353a6 100644
--- a/drivers/video/udlfb.c
+++ b/drivers/video/udlfb.c
@@ -434,10 +434,10 @@ static void dlfb_compress_hline(
while ((pixel_end > pixel) &&
(cmd_buffer_end - MIN_RLX_CMD_BYTES > cmd)) {
- uint8_t *raw_pixels_count_byte = 0;
- uint8_t *cmd_pixels_count_byte = 0;
- const uint16_t *raw_pixel_start = 0;
- const uint16_t *cmd_pixel_start, *cmd_pixel_end = 0;
+ uint8_t *raw_pixels_count_byte = NULL;
+ uint8_t *cmd_pixels_count_byte = NULL;
+ const uint16_t *raw_pixel_start = NULL;
+ const uint16_t *cmd_pixel_start, *cmd_pixel_end = NULL;
prefetchw((void *) cmd); /* pull in one cache line at least */
@@ -1588,7 +1588,7 @@ static int dlfb_usb_probe(struct usb_interface *interface,
const struct usb_device_id *id)
{
struct usb_device *usbdev;
- struct dlfb_data *dev = 0;
+ struct dlfb_data *dev = NULL;
int retval = -ENOMEM;
/* usb initialization */
--
1.7.9.5
^ permalink raw reply related
* [PATCH 2/2] video: udlfb: Make local symbol static
From: Sachin Kamat @ 2013-05-10 11:58 UTC (permalink / raw)
To: linux-fbdev
'dlfb_handle_damage' is used only in this file. Make it static.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
---
drivers/video/udlfb.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/video/udlfb.c b/drivers/video/udlfb.c
index 20353a6..d2e5bc3 100644
--- a/drivers/video/udlfb.c
+++ b/drivers/video/udlfb.c
@@ -573,7 +573,7 @@ static int dlfb_render_hline(struct dlfb_data *dev, struct urb **urb_ptr,
return 0;
}
-int dlfb_handle_damage(struct dlfb_data *dev, int x, int y,
+static int dlfb_handle_damage(struct dlfb_data *dev, int x, int y,
int width, int height, char *data)
{
int i, ret;
--
1.7.9.5
^ permalink raw reply related
* [PATCH 1/1] video: imxfb: Make local symbols static
From: Sachin Kamat @ 2013-05-10 12:07 UTC (permalink / raw)
To: linux-fbdev
These symbols are used only in this file.
Make them static.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
---
drivers/video/imxfb.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/video/imxfb.c b/drivers/video/imxfb.c
index 0abf2bf..0a16d82 100644
--- a/drivers/video/imxfb.c
+++ b/drivers/video/imxfb.c
@@ -960,7 +960,7 @@ static int imxfb_remove(struct platform_device *pdev)
return 0;
}
-void imxfb_shutdown(struct platform_device * dev)
+static void imxfb_shutdown(struct platform_device *dev)
{
struct fb_info *info = platform_get_drvdata(dev);
struct imxfb_info *fbi = info->par;
@@ -999,7 +999,7 @@ static int imxfb_setup(void)
return 0;
}
-int __init imxfb_init(void)
+static int __init imxfb_init(void)
{
int ret = imxfb_setup();
--
1.7.9.5
^ permalink raw reply related
* Re: [PATCH 1/1] video: smscufx: Use NULL instead of 0
From: Steve Glendinning @ 2013-05-10 16:21 UTC (permalink / raw)
To: linux-fbdev
In-Reply-To: <1368185707-12852-1-git-send-email-sachin.kamat@linaro.org>
> 'info' is a pointer. Use NULL instead of 0.
>
> Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Steve Glendinning <steve.glendinning@shawell.net>
^ permalink raw reply
* Re: [RFC/PATCH v2 1/8] Add arch_phys_wc_{add,del} to manipulate WC MTRRs if needed
From: Andy Lutomirski @ 2013-05-10 18:00 UTC (permalink / raw)
To: Andy Lutomirski, linux-kernel, dri-devel, linux-fbdev,
Jerome Glisse, Alex Deucher, Dave Airlie
Cc: Daniel Vetter
In-Reply-To: <20130510091923.GH12292@phenom.ffwll.local>
On Fri, May 10, 2013 at 2:19 AM, Daniel Vetter <daniel@ffwll.ch> wrote:
> On Thu, May 09, 2013 at 12:46:20PM -0700, Andy Lutomirski wrote:
>> Several drivers currently use mtrr_add through various #ifdef guards
>> and/or drm wrappers. The vast majority of them want to add WC MTRRs
>> on x86 systems and don't actually need the MTRR if PAT (i.e.
>> ioremap_wc, etc) are working.
>>
>> arch_phys_wc_add and arch_phys_wc_del are new functions, available
>> on all architectures and configurations, that add WC MTRRs on x86 if
>> needed (and handle errors) and do nothing at all otherwise. They're
>> also easier to use than mtrr_add and mtrr_del, so the call sites can
>> be simplified.
>>
>> As an added benefit, this will avoid wasting MTRRs and possibly
>> warning pointlessly on PAT-supporting systems.
>>
>> Signed-off-by: Andy Lutomirski <luto@amacapital.net>
>> ---
>> arch/x86/include/asm/io.h | 7 ++++++
>> arch/x86/include/asm/mtrr.h | 5 ++++-
>> arch/x86/kernel/cpu/mtrr/main.c | 48 +++++++++++++++++++++++++++++++++++++++++
>> include/linux/io.h | 25 +++++++++++++++++++++
>> 4 files changed, 84 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
>> index d8e8eef..34f69cb 100644
>> --- a/arch/x86/include/asm/io.h
>> +++ b/arch/x86/include/asm/io.h
>> @@ -345,4 +345,11 @@ extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
>>
>> #define IO_SPACE_LIMIT 0xffff
>>
>> +#ifdef CONFIG_MTRR
>> +extern int __must_check arch_phys_wc_add(unsigned long base,
>> + unsigned long size);
>> +extern void arch_phys_wc_del(int handle);
>> +#define arch_phys_wc_add arch_phys_wc_add
>> +#endif
>> +
>> #endif /* _ASM_X86_IO_H */
>> diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h
>> index e235582..10d0fba 100644
>> --- a/arch/x86/include/asm/mtrr.h
>> +++ b/arch/x86/include/asm/mtrr.h
>> @@ -26,7 +26,10 @@
>> #include <uapi/asm/mtrr.h>
>>
>>
>> -/* The following functions are for use by other drivers */
>> +/*
>> + * The following functions are for use by other drivers that cannot use
>> + * arch_phys_wc_add and arch_phys_wc_del.
>> + */
>> # ifdef CONFIG_MTRR
>> extern u8 mtrr_type_lookup(u64 addr, u64 end);
>> extern void mtrr_save_fixed_ranges(void *);
>> diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c
>> index 726bf96..23bd49a 100644
>> --- a/arch/x86/kernel/cpu/mtrr/main.c
>> +++ b/arch/x86/kernel/cpu/mtrr/main.c
>> @@ -51,6 +51,7 @@
>> #include <asm/e820.h>
>> #include <asm/mtrr.h>
>> #include <asm/msr.h>
>> +#include <asm/pat.h>
>>
>> #include "mtrr.h"
>>
>> @@ -524,6 +525,53 @@ int mtrr_del(int reg, unsigned long base, unsigned long size)
>> }
>> EXPORT_SYMBOL(mtrr_del);
>>
>> +/**
>> + * arch_phys_wc_add - add a WC MTRR and handle errors if PAT is unavailable
>> + * @base: Physical base address
>> + * @size: Size of region
>> + *
>> + * If PAT is available, this does nothing. If PAT is unavailable, it
>> + * attempts to add a WC MTRR covering size bytes starting at base and
>> + * logs an error if this fails.
>> + *
>> + * Drivers must store the return value to pass to mtrr_del_wc_if_needed,
>> + * but drivers should not try to interpret that return value.
>> + */
>> +int arch_phys_wc_add(unsigned long base, unsigned long size)
>> +{
>> + int ret;
>> +
>> + if (pat_enabled)
>> + return 0; /* Success! (We don't need to do anything.) */
>
> Shouldn't we #define a big number for this case since mtrr_add returns
> 0-based mtrr indices? Rather unlikely that the very first mtrr is unused I
> know, but still feels like a cleaner interface. And we don't need to leak
> that #define out at all to users of this interface.
I did something more like that in v1, but I like having the property
that arch_phys_wc_del(0) does nothing as opposed to possibly breaking
the system. Given that almost all of these things are stored in
kzalloced space, this seems safer to me. The return value here could
just as easily be -ENOSYS, but nothing should care.
There is an issue, though: the drm maps interface is leaking the
return values to userspace via a couple of ioctls, so I should fix it
to at least return the correct value. (Why that interface includes an
mtrr number is a mystery to me.)
Have I convinced you that my bike shed color is okay? I'll send out a
v3 later today with a fix for the leaking-to-userspace issue and I'll
fix the i915 thing.
--Andy
^ permalink raw reply
* Re: [RFC/PATCH v2 1/8] Add arch_phys_wc_{add,del} to manipulate WC MTRRs if needed
From: Daniel Vetter @ 2013-05-10 19:09 UTC (permalink / raw)
To: Andy Lutomirski
Cc: linux-kernel, dri-devel, linux-fbdev, Jerome Glisse, Alex Deucher,
Dave Airlie, Daniel Vetter
In-Reply-To: <CALCETrVQzMjxZ87zY=+-TUKAMARnR9m3CzYdWZgEopJxF0TkDw@mail.gmail.com>
On Fri, May 10, 2013 at 11:00:56AM -0700, Andy Lutomirski wrote:
> On Fri, May 10, 2013 at 2:19 AM, Daniel Vetter <daniel@ffwll.ch> wrote:
> > On Thu, May 09, 2013 at 12:46:20PM -0700, Andy Lutomirski wrote:
> >> Several drivers currently use mtrr_add through various #ifdef guards
> >> and/or drm wrappers. The vast majority of them want to add WC MTRRs
> >> on x86 systems and don't actually need the MTRR if PAT (i.e.
> >> ioremap_wc, etc) are working.
> >>
> >> arch_phys_wc_add and arch_phys_wc_del are new functions, available
> >> on all architectures and configurations, that add WC MTRRs on x86 if
> >> needed (and handle errors) and do nothing at all otherwise. They're
> >> also easier to use than mtrr_add and mtrr_del, so the call sites can
> >> be simplified.
> >>
> >> As an added benefit, this will avoid wasting MTRRs and possibly
> >> warning pointlessly on PAT-supporting systems.
> >>
> >> Signed-off-by: Andy Lutomirski <luto@amacapital.net>
> >> ---
> >> arch/x86/include/asm/io.h | 7 ++++++
> >> arch/x86/include/asm/mtrr.h | 5 ++++-
> >> arch/x86/kernel/cpu/mtrr/main.c | 48 +++++++++++++++++++++++++++++++++++++++++
> >> include/linux/io.h | 25 +++++++++++++++++++++
> >> 4 files changed, 84 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
> >> index d8e8eef..34f69cb 100644
> >> --- a/arch/x86/include/asm/io.h
> >> +++ b/arch/x86/include/asm/io.h
> >> @@ -345,4 +345,11 @@ extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
> >>
> >> #define IO_SPACE_LIMIT 0xffff
> >>
> >> +#ifdef CONFIG_MTRR
> >> +extern int __must_check arch_phys_wc_add(unsigned long base,
> >> + unsigned long size);
> >> +extern void arch_phys_wc_del(int handle);
> >> +#define arch_phys_wc_add arch_phys_wc_add
> >> +#endif
> >> +
> >> #endif /* _ASM_X86_IO_H */
> >> diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h
> >> index e235582..10d0fba 100644
> >> --- a/arch/x86/include/asm/mtrr.h
> >> +++ b/arch/x86/include/asm/mtrr.h
> >> @@ -26,7 +26,10 @@
> >> #include <uapi/asm/mtrr.h>
> >>
> >>
> >> -/* The following functions are for use by other drivers */
> >> +/*
> >> + * The following functions are for use by other drivers that cannot use
> >> + * arch_phys_wc_add and arch_phys_wc_del.
> >> + */
> >> # ifdef CONFIG_MTRR
> >> extern u8 mtrr_type_lookup(u64 addr, u64 end);
> >> extern void mtrr_save_fixed_ranges(void *);
> >> diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c
> >> index 726bf96..23bd49a 100644
> >> --- a/arch/x86/kernel/cpu/mtrr/main.c
> >> +++ b/arch/x86/kernel/cpu/mtrr/main.c
> >> @@ -51,6 +51,7 @@
> >> #include <asm/e820.h>
> >> #include <asm/mtrr.h>
> >> #include <asm/msr.h>
> >> +#include <asm/pat.h>
> >>
> >> #include "mtrr.h"
> >>
> >> @@ -524,6 +525,53 @@ int mtrr_del(int reg, unsigned long base, unsigned long size)
> >> }
> >> EXPORT_SYMBOL(mtrr_del);
> >>
> >> +/**
> >> + * arch_phys_wc_add - add a WC MTRR and handle errors if PAT is unavailable
> >> + * @base: Physical base address
> >> + * @size: Size of region
> >> + *
> >> + * If PAT is available, this does nothing. If PAT is unavailable, it
> >> + * attempts to add a WC MTRR covering size bytes starting at base and
> >> + * logs an error if this fails.
> >> + *
> >> + * Drivers must store the return value to pass to mtrr_del_wc_if_needed,
> >> + * but drivers should not try to interpret that return value.
> >> + */
> >> +int arch_phys_wc_add(unsigned long base, unsigned long size)
> >> +{
> >> + int ret;
> >> +
> >> + if (pat_enabled)
> >> + return 0; /* Success! (We don't need to do anything.) */
> >
> > Shouldn't we #define a big number for this case since mtrr_add returns
> > 0-based mtrr indices? Rather unlikely that the very first mtrr is unused I
> > know, but still feels like a cleaner interface. And we don't need to leak
> > that #define out at all to users of this interface.
>
> I did something more like that in v1, but I like having the property
> that arch_phys_wc_del(0) does nothing as opposed to possibly breaking
> the system. Given that almost all of these things are stored in
> kzalloced space, this seems safer to me. The return value here could
> just as easily be -ENOSYS, but nothing should care.
>
> There is an issue, though: the drm maps interface is leaking the
> return values to userspace via a couple of ioctls, so I should fix it
> to at least return the correct value. (Why that interface includes an
> mtrr number is a mystery to me.)
Old drm interfaces are horrible. Best approach is to simply stay far away
from them ...
> Have I convinced you that my bike shed color is okay? I'll send out a
> v3 later today with a fix for the leaking-to-userspace issue and I'll
> fix the i915 thing.
A comment in your arch_phys_wc_add/del functions that we do have an mtrr
with index 0, but won't ever get that would be fine with me. Still feels a
bit irky though ;-)
Cheers, Daniel
--
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch
^ permalink raw reply
* Re: [RFC/PATCH v2 1/8] Add arch_phys_wc_{add,del} to manipulate WC MTRRs if needed
From: Andy Lutomirski @ 2013-05-10 19:27 UTC (permalink / raw)
To: Andy Lutomirski, linux-kernel, dri-devel, linux-fbdev,
Jerome Glisse, Alex Deucher, Dave Airlie
Cc: Daniel Vetter
In-Reply-To: <20130510190954.GS12292@phenom.ffwll.local>
On Fri, May 10, 2013 at 12:09 PM, Daniel Vetter <daniel@ffwll.ch> wrote:
> On Fri, May 10, 2013 at 11:00:56AM -0700, Andy Lutomirski wrote:
>> On Fri, May 10, 2013 at 2:19 AM, Daniel Vetter <daniel@ffwll.ch> wrote:
>> > On Thu, May 09, 2013 at 12:46:20PM -0700, Andy Lutomirski wrote:
>> >> Several drivers currently use mtrr_add through various #ifdef guards
>> >> and/or drm wrappers. The vast majority of them want to add WC MTRRs
>> >> on x86 systems and don't actually need the MTRR if PAT (i.e.
>> >> ioremap_wc, etc) are working.
>> >>
>> >> arch_phys_wc_add and arch_phys_wc_del are new functions, available
>> >> on all architectures and configurations, that add WC MTRRs on x86 if
>> >> needed (and handle errors) and do nothing at all otherwise. They're
>> >> also easier to use than mtrr_add and mtrr_del, so the call sites can
>> >> be simplified.
>> >>
>> >> As an added benefit, this will avoid wasting MTRRs and possibly
>> >> warning pointlessly on PAT-supporting systems.
>> >>
>> >> Signed-off-by: Andy Lutomirski <luto@amacapital.net>
>> >> ---
>> >> arch/x86/include/asm/io.h | 7 ++++++
>> >> arch/x86/include/asm/mtrr.h | 5 ++++-
>> >> arch/x86/kernel/cpu/mtrr/main.c | 48 +++++++++++++++++++++++++++++++++++++++++
>> >> include/linux/io.h | 25 +++++++++++++++++++++
>> >> 4 files changed, 84 insertions(+), 1 deletion(-)
>> >>
>> >> diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
>> >> index d8e8eef..34f69cb 100644
>> >> --- a/arch/x86/include/asm/io.h
>> >> +++ b/arch/x86/include/asm/io.h
>> >> @@ -345,4 +345,11 @@ extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
>> >>
>> >> #define IO_SPACE_LIMIT 0xffff
>> >>
>> >> +#ifdef CONFIG_MTRR
>> >> +extern int __must_check arch_phys_wc_add(unsigned long base,
>> >> + unsigned long size);
>> >> +extern void arch_phys_wc_del(int handle);
>> >> +#define arch_phys_wc_add arch_phys_wc_add
>> >> +#endif
>> >> +
>> >> #endif /* _ASM_X86_IO_H */
>> >> diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h
>> >> index e235582..10d0fba 100644
>> >> --- a/arch/x86/include/asm/mtrr.h
>> >> +++ b/arch/x86/include/asm/mtrr.h
>> >> @@ -26,7 +26,10 @@
>> >> #include <uapi/asm/mtrr.h>
>> >>
>> >>
>> >> -/* The following functions are for use by other drivers */
>> >> +/*
>> >> + * The following functions are for use by other drivers that cannot use
>> >> + * arch_phys_wc_add and arch_phys_wc_del.
>> >> + */
>> >> # ifdef CONFIG_MTRR
>> >> extern u8 mtrr_type_lookup(u64 addr, u64 end);
>> >> extern void mtrr_save_fixed_ranges(void *);
>> >> diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c
>> >> index 726bf96..23bd49a 100644
>> >> --- a/arch/x86/kernel/cpu/mtrr/main.c
>> >> +++ b/arch/x86/kernel/cpu/mtrr/main.c
>> >> @@ -51,6 +51,7 @@
>> >> #include <asm/e820.h>
>> >> #include <asm/mtrr.h>
>> >> #include <asm/msr.h>
>> >> +#include <asm/pat.h>
>> >>
>> >> #include "mtrr.h"
>> >>
>> >> @@ -524,6 +525,53 @@ int mtrr_del(int reg, unsigned long base, unsigned long size)
>> >> }
>> >> EXPORT_SYMBOL(mtrr_del);
>> >>
>> >> +/**
>> >> + * arch_phys_wc_add - add a WC MTRR and handle errors if PAT is unavailable
>> >> + * @base: Physical base address
>> >> + * @size: Size of region
>> >> + *
>> >> + * If PAT is available, this does nothing. If PAT is unavailable, it
>> >> + * attempts to add a WC MTRR covering size bytes starting at base and
>> >> + * logs an error if this fails.
>> >> + *
>> >> + * Drivers must store the return value to pass to mtrr_del_wc_if_needed,
>> >> + * but drivers should not try to interpret that return value.
>> >> + */
>> >> +int arch_phys_wc_add(unsigned long base, unsigned long size)
>> >> +{
>> >> + int ret;
>> >> +
>> >> + if (pat_enabled)
>> >> + return 0; /* Success! (We don't need to do anything.) */
>> >
>> > Shouldn't we #define a big number for this case since mtrr_add returns
>> > 0-based mtrr indices? Rather unlikely that the very first mtrr is unused I
>> > know, but still feels like a cleaner interface. And we don't need to leak
>> > that #define out at all to users of this interface.
>>
>> I did something more like that in v1, but I like having the property
>> that arch_phys_wc_del(0) does nothing as opposed to possibly breaking
>> the system. Given that almost all of these things are stored in
>> kzalloced space, this seems safer to me. The return value here could
>> just as easily be -ENOSYS, but nothing should care.
>>
>> There is an issue, though: the drm maps interface is leaking the
>> return values to userspace via a couple of ioctls, so I should fix it
>> to at least return the correct value. (Why that interface includes an
>> mtrr number is a mystery to me.)
>
> Old drm interfaces are horrible. Best approach is to simply stay far away
> from them ...
>
>> Have I convinced you that my bike shed color is okay? I'll send out a
>> v3 later today with a fix for the leaking-to-userspace issue and I'll
>> fix the i915 thing.
>
> A comment in your arch_phys_wc_add/del functions that we do have an mtrr
> with index 0, but won't ever get that would be fine with me. Still feels a
> bit irky though ;-)
Hmm. Maybe you missed the hack I ended up using a couple of lines
below. I'm always using strictly positive values to indicate a real
MTRR -- I'm adding 1000 to the result if we actually do anything. So
a return value of 0 is genuinely safe. (I still have to fix up the
two places in the drm code that pass that hacked-up value back to
userspace.)
--Andy
^ permalink raw reply
* Re: [RFC/PATCH v2 1/8] Add arch_phys_wc_{add,del} to manipulate WC MTRRs if needed
From: Daniel Vetter @ 2013-05-10 19:34 UTC (permalink / raw)
To: Andy Lutomirski
Cc: linux-kernel, dri-devel, linux-fbdev, Jerome Glisse, Alex Deucher,
Dave Airlie, Daniel Vetter
In-Reply-To: <CALCETrXbO9ePZf5nUZQXG1LSr8N7XCw34QKj7EqAF1sY3L1UdQ@mail.gmail.com>
On Fri, May 10, 2013 at 12:27:54PM -0700, Andy Lutomirski wrote:
> On Fri, May 10, 2013 at 12:09 PM, Daniel Vetter <daniel@ffwll.ch> wrote:
> > On Fri, May 10, 2013 at 11:00:56AM -0700, Andy Lutomirski wrote:
> >> On Fri, May 10, 2013 at 2:19 AM, Daniel Vetter <daniel@ffwll.ch> wrote:
> >> > On Thu, May 09, 2013 at 12:46:20PM -0700, Andy Lutomirski wrote:
> >> >> Several drivers currently use mtrr_add through various #ifdef guards
> >> >> and/or drm wrappers. The vast majority of them want to add WC MTRRs
> >> >> on x86 systems and don't actually need the MTRR if PAT (i.e.
> >> >> ioremap_wc, etc) are working.
> >> >>
> >> >> arch_phys_wc_add and arch_phys_wc_del are new functions, available
> >> >> on all architectures and configurations, that add WC MTRRs on x86 if
> >> >> needed (and handle errors) and do nothing at all otherwise. They're
> >> >> also easier to use than mtrr_add and mtrr_del, so the call sites can
> >> >> be simplified.
> >> >>
> >> >> As an added benefit, this will avoid wasting MTRRs and possibly
> >> >> warning pointlessly on PAT-supporting systems.
> >> >>
> >> >> Signed-off-by: Andy Lutomirski <luto@amacapital.net>
> >> >> ---
> >> >> arch/x86/include/asm/io.h | 7 ++++++
> >> >> arch/x86/include/asm/mtrr.h | 5 ++++-
> >> >> arch/x86/kernel/cpu/mtrr/main.c | 48 +++++++++++++++++++++++++++++++++++++++++
> >> >> include/linux/io.h | 25 +++++++++++++++++++++
> >> >> 4 files changed, 84 insertions(+), 1 deletion(-)
> >> >>
> >> >> diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
> >> >> index d8e8eef..34f69cb 100644
> >> >> --- a/arch/x86/include/asm/io.h
> >> >> +++ b/arch/x86/include/asm/io.h
> >> >> @@ -345,4 +345,11 @@ extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
> >> >>
> >> >> #define IO_SPACE_LIMIT 0xffff
> >> >>
> >> >> +#ifdef CONFIG_MTRR
> >> >> +extern int __must_check arch_phys_wc_add(unsigned long base,
> >> >> + unsigned long size);
> >> >> +extern void arch_phys_wc_del(int handle);
> >> >> +#define arch_phys_wc_add arch_phys_wc_add
> >> >> +#endif
> >> >> +
> >> >> #endif /* _ASM_X86_IO_H */
> >> >> diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h
> >> >> index e235582..10d0fba 100644
> >> >> --- a/arch/x86/include/asm/mtrr.h
> >> >> +++ b/arch/x86/include/asm/mtrr.h
> >> >> @@ -26,7 +26,10 @@
> >> >> #include <uapi/asm/mtrr.h>
> >> >>
> >> >>
> >> >> -/* The following functions are for use by other drivers */
> >> >> +/*
> >> >> + * The following functions are for use by other drivers that cannot use
> >> >> + * arch_phys_wc_add and arch_phys_wc_del.
> >> >> + */
> >> >> # ifdef CONFIG_MTRR
> >> >> extern u8 mtrr_type_lookup(u64 addr, u64 end);
> >> >> extern void mtrr_save_fixed_ranges(void *);
> >> >> diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c
> >> >> index 726bf96..23bd49a 100644
> >> >> --- a/arch/x86/kernel/cpu/mtrr/main.c
> >> >> +++ b/arch/x86/kernel/cpu/mtrr/main.c
> >> >> @@ -51,6 +51,7 @@
> >> >> #include <asm/e820.h>
> >> >> #include <asm/mtrr.h>
> >> >> #include <asm/msr.h>
> >> >> +#include <asm/pat.h>
> >> >>
> >> >> #include "mtrr.h"
> >> >>
> >> >> @@ -524,6 +525,53 @@ int mtrr_del(int reg, unsigned long base, unsigned long size)
> >> >> }
> >> >> EXPORT_SYMBOL(mtrr_del);
> >> >>
> >> >> +/**
> >> >> + * arch_phys_wc_add - add a WC MTRR and handle errors if PAT is unavailable
> >> >> + * @base: Physical base address
> >> >> + * @size: Size of region
> >> >> + *
> >> >> + * If PAT is available, this does nothing. If PAT is unavailable, it
> >> >> + * attempts to add a WC MTRR covering size bytes starting at base and
> >> >> + * logs an error if this fails.
> >> >> + *
> >> >> + * Drivers must store the return value to pass to mtrr_del_wc_if_needed,
> >> >> + * but drivers should not try to interpret that return value.
> >> >> + */
> >> >> +int arch_phys_wc_add(unsigned long base, unsigned long size)
> >> >> +{
> >> >> + int ret;
> >> >> +
> >> >> + if (pat_enabled)
> >> >> + return 0; /* Success! (We don't need to do anything.) */
> >> >
> >> > Shouldn't we #define a big number for this case since mtrr_add returns
> >> > 0-based mtrr indices? Rather unlikely that the very first mtrr is unused I
> >> > know, but still feels like a cleaner interface. And we don't need to leak
> >> > that #define out at all to users of this interface.
> >>
> >> I did something more like that in v1, but I like having the property
> >> that arch_phys_wc_del(0) does nothing as opposed to possibly breaking
> >> the system. Given that almost all of these things are stored in
> >> kzalloced space, this seems safer to me. The return value here could
> >> just as easily be -ENOSYS, but nothing should care.
> >>
> >> There is an issue, though: the drm maps interface is leaking the
> >> return values to userspace via a couple of ioctls, so I should fix it
> >> to at least return the correct value. (Why that interface includes an
> >> mtrr number is a mystery to me.)
> >
> > Old drm interfaces are horrible. Best approach is to simply stay far away
> > from them ...
> >
> >> Have I convinced you that my bike shed color is okay? I'll send out a
> >> v3 later today with a fix for the leaking-to-userspace issue and I'll
> >> fix the i915 thing.
> >
> > A comment in your arch_phys_wc_add/del functions that we do have an mtrr
> > with index 0, but won't ever get that would be fine with me. Still feels a
> > bit irky though ;-)
>
> Hmm. Maybe you missed the hack I ended up using a couple of lines
> below. I'm always using strictly positive values to indicate a real
> MTRR -- I'm adding 1000 to the result if we actually do anything. So
> a return value of 0 is genuinely safe. (I still have to fix up the
> two places in the drm code that pass that hacked-up value back to
> userspace.)
Oops, I've indeed missed that one. Only noticed the special 0 and started
hunting down the semantics of mtrr_add. With that cleared up this is
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
--
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch
^ permalink raw reply
* Re: [RFC 32/42] drivers/video: don't check resource with devm_ioremap_resource
From: Jingoo Han @ 2013-05-11 5:33 UTC (permalink / raw)
To: 'Wolfram Sang', linux-kernel
Cc: 'Florian Tobias Schandinat', linux-fbdev,
'Tomi Valkeinen', 'Shawn Guo', Fabio Estevam
In-Reply-To: <1368173847-5661-33-git-send-email-wsa@the-dreams.de>
On Friday, May 10, 2013 5:17 PM, Wolfram Sang wrote:
>
> devm_ioremap_resource does sanity checks on the given resource. No need to
> duplicate this in the driver.
>
> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
CC'ed Tomi Valkeinen, Shawn Guo, Fabio Estevam
It looks good.
Reviewed-by: Jingoo Han <jg1.han@samsung.com>
Best regards,
Jingoo Han
> ---
> drivers/video/mxsfb.c | 7 +------
> 1 file changed, 1 insertion(+), 6 deletions(-)
>
> diff --git a/drivers/video/mxsfb.c b/drivers/video/mxsfb.c
> index 1b2c26d..3dc3265 100644
> --- a/drivers/video/mxsfb.c
> +++ b/drivers/video/mxsfb.c
> @@ -883,12 +883,6 @@ static int mxsfb_probe(struct platform_device *pdev)
> if (of_id)
> pdev->id_entry = of_id->data;
>
> - res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> - if (!res) {
> - dev_err(&pdev->dev, "Cannot get memory IO resource\n");
> - return -ENODEV;
> - }
> -
> fb_info = framebuffer_alloc(sizeof(struct mxsfb_info), &pdev->dev);
> if (!fb_info) {
> dev_err(&pdev->dev, "Failed to allocate fbdev\n");
> @@ -897,6 +891,7 @@ static int mxsfb_probe(struct platform_device *pdev)
>
> host = to_imxfb_host(fb_info);
>
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> host->base = devm_ioremap_resource(&pdev->dev, res);
> if (IS_ERR(host->base)) {
> dev_err(&pdev->dev, "ioremap failed\n");
> --
> 1.7.10.4
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply
* Re: [RFC 34/42] drivers/video/omap2/dss: don't check resource with devm_ioremap_resource
From: Jingoo Han @ 2013-05-11 5:36 UTC (permalink / raw)
To: 'Wolfram Sang', linux-kernel
Cc: 'Tomi Valkeinen', 'Florian Tobias Schandinat',
linux-omap, linux-fbdev
In-Reply-To: <1368173847-5661-35-git-send-email-wsa@the-dreams.de>
On Friday, May 10, 2013 5:17 PM, Wolfram Sang wrote:
>
> devm_ioremap_resource does sanity checks on the given resource. No need to
> duplicate this in the driver.
>
> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
It looks good.
Reviewed-by: Jingoo Han <jg1.han@samsung.com>
Best regards,
Jingoo Han
> ---
> drivers/video/omap2/dss/hdmi.c | 7 +------
> 1 file changed, 1 insertion(+), 6 deletions(-)
>
> diff --git a/drivers/video/omap2/dss/hdmi.c b/drivers/video/omap2/dss/hdmi.c
> index 17f4d55..7bc6762 100644
> --- a/drivers/video/omap2/dss/hdmi.c
> +++ b/drivers/video/omap2/dss/hdmi.c
> @@ -1064,13 +1064,8 @@ static int omapdss_hdmihw_probe(struct platform_device *pdev)
> mutex_init(&hdmi.lock);
> mutex_init(&hdmi.ip_data.lock);
>
> - res = platform_get_resource(hdmi.pdev, IORESOURCE_MEM, 0);
> - if (!res) {
> - DSSERR("can't get IORESOURCE_MEM HDMI\n");
> - return -EINVAL;
> - }
> -
> /* Base address taken from platform */
> + res = platform_get_resource(hdmi.pdev, IORESOURCE_MEM, 0);
> hdmi.ip_data.base_wp = devm_ioremap_resource(&pdev->dev, res);
> if (IS_ERR(hdmi.ip_data.base_wp))
> return PTR_ERR(hdmi.ip_data.base_wp);
> --
> 1.7.10.4
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply
page: next (older) | prev (newer) | latest
- recent:[subjects (threaded)|topics (new)|topics (active)]
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox