summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--Documentation/x86/mtrr.txt20
-rw-r--r--arch/avr32/include/asm/io.h1
-rw-r--r--arch/frv/include/asm/io.h1
-rw-r--r--arch/m32r/include/asm/io.h1
-rw-r--r--arch/m68k/include/asm/io_mm.h1
-rw-r--r--arch/mn10300/include/asm/io.h1
-rw-r--r--arch/powerpc/include/asm/io.h1
-rw-r--r--arch/s390/include/asm/io.h2
-rw-r--r--arch/sh/include/asm/io.h1
-rw-r--r--arch/tile/include/asm/io.h1
-rw-r--r--arch/x86/include/asm/io.h2
-rw-r--r--arch/x86/kernel/check.c5
-rw-r--r--arch/x86/kernel/cpu/mtrr/main.c2
-rw-r--r--arch/x86/mm/init.c7
-rw-r--r--arch/x86/mm/init_32.c1
-rw-r--r--arch/x86/mm/pageattr-test.c4
-rw-r--r--arch/x86/mm/pageattr.c1
-rw-r--r--drivers/dma/iop-adma.c9
-rw-r--r--drivers/pci/pci.c14
-rw-r--r--drivers/video/fbdev/arkfb.c36
-rw-r--r--drivers/video/fbdev/aty/atyfb.h5
-rw-r--r--drivers/video/fbdev/aty/atyfb_base.c109
-rw-r--r--drivers/video/fbdev/gxt4500.c2
-rw-r--r--drivers/video/fbdev/i740fb.c35
-rw-r--r--drivers/video/fbdev/kyro/fbdev.c33
-rw-r--r--drivers/video/fbdev/s3fb.c35
-rw-r--r--drivers/video/fbdev/vt8623fb.c31
-rw-r--r--include/asm-generic/io.h30
-rw-r--r--include/asm-generic/pci_iomap.h14
-rw-r--r--include/linux/pci.h1
-rw-r--r--include/video/kyro.h4
-rw-r--r--lib/pci_iomap.c66
32 files changed, 254 insertions, 222 deletions
diff --git a/Documentation/x86/mtrr.txt b/Documentation/x86/mtrr.txt
index 860bc3adc223..dc3e703913ac 100644
--- a/Documentation/x86/mtrr.txt
+++ b/Documentation/x86/mtrr.txt
@@ -6,10 +6,22 @@ Luis R. Rodriguez <mcgrof@do-not-panic.com> - April 9, 2015
===============================================================================
Phasing out MTRR use
-MTRR use is replaced on modern x86 hardware with PAT. Over time the only type
-of effective MTRR that is expected to be supported will be for write-combining.
-As MTRR use is phased out device drivers should use arch_phys_wc_add() to make
-MTRR effective on non-PAT systems while a no-op on PAT enabled systems.
+MTRR use is replaced on modern x86 hardware with PAT. Direct MTRR use by
+drivers on Linux is now completely phased out, device drivers should use
+arch_phys_wc_add() in combination with ioremap_wc() to make MTRR effective on
+non-PAT systems while a no-op but equally effective on PAT enabled systems.
+
+Even if Linux does not use MTRRs directly, some x86 platform firmware may still
+set up MTRRs early before booting the OS. They do this as some platform
+firmware may still have implemented access to MTRRs which would be controlled
+and handled by the platform firmware directly. An example of platform use of
+MTRRs is through the use of SMI handlers, one case could be for fan control,
+the platform code would need uncachable access to some of its fan control
+registers. Such platform access does not need any Operating System MTRR code in
+place other than mtrr_type_lookup() to ensure any OS specific mapping requests
+are aligned with platform MTRR setup. If MTRRs are only set up by the platform
+firmware code though and the OS does not make any specific MTRR mapping
+requests mtrr_type_lookup() should always return MTRR_TYPE_INVALID.
For details refer to Documentation/x86/pat.txt.
diff --git a/arch/avr32/include/asm/io.h b/arch/avr32/include/asm/io.h
index e998ff5d8e1a..f855646e0db7 100644
--- a/arch/avr32/include/asm/io.h
+++ b/arch/avr32/include/asm/io.h
@@ -297,6 +297,7 @@ extern void __iounmap(void __iomem *addr);
#define ioremap_wc ioremap_nocache
#define ioremap_wt ioremap_nocache
+#define ioremap_uc ioremap_nocache
#define cached(addr) P1SEGADDR(addr)
#define uncached(addr) P2SEGADDR(addr)
diff --git a/arch/frv/include/asm/io.h b/arch/frv/include/asm/io.h
index a31b63ec4930..70dfbea8c8d7 100644
--- a/arch/frv/include/asm/io.h
+++ b/arch/frv/include/asm/io.h
@@ -278,6 +278,7 @@ static inline void __iomem *ioremap_fullcache(unsigned long physaddr, unsigned l
}
#define ioremap_wc ioremap_nocache
+#define ioremap_uc ioremap_nocache
extern void iounmap(void volatile __iomem *addr);
diff --git a/arch/m32r/include/asm/io.h b/arch/m32r/include/asm/io.h
index f8de767ce2bc..61b8931bc192 100644
--- a/arch/m32r/include/asm/io.h
+++ b/arch/m32r/include/asm/io.h
@@ -69,6 +69,7 @@ extern void iounmap(volatile void __iomem *addr);
#define ioremap_nocache(off,size) ioremap(off,size)
#define ioremap_wc ioremap_nocache
#define ioremap_wt ioremap_nocache
+#define ioremap_uc ioremap_nocache
/*
* IO bus memory addresses are also 1:1 with the physical address
diff --git a/arch/m68k/include/asm/io_mm.h b/arch/m68k/include/asm/io_mm.h
index f55cad529400..c98ac81582ac 100644
--- a/arch/m68k/include/asm/io_mm.h
+++ b/arch/m68k/include/asm/io_mm.h
@@ -468,6 +468,7 @@ static inline void __iomem *ioremap_nocache(unsigned long physaddr, unsigned lon
{
return __ioremap(physaddr, size, IOMAP_NOCACHE_SER);
}
+#define ioremap_uc ioremap_nocache
static inline void __iomem *ioremap_wt(unsigned long physaddr,
unsigned long size)
{
diff --git a/arch/mn10300/include/asm/io.h b/arch/mn10300/include/asm/io.h
index 07c5b4a3903b..62189353d2f6 100644
--- a/arch/mn10300/include/asm/io.h
+++ b/arch/mn10300/include/asm/io.h
@@ -283,6 +283,7 @@ static inline void __iomem *ioremap_nocache(unsigned long offset, unsigned long
#define ioremap_wc ioremap_nocache
#define ioremap_wt ioremap_nocache
+#define ioremap_uc ioremap_nocache
static inline void iounmap(void __iomem *addr)
{
diff --git a/arch/powerpc/include/asm/io.h b/arch/powerpc/include/asm/io.h
index a8d2ef30d473..5879fde56f3c 100644
--- a/arch/powerpc/include/asm/io.h
+++ b/arch/powerpc/include/asm/io.h
@@ -721,6 +721,7 @@ extern void __iomem *ioremap_prot(phys_addr_t address, unsigned long size,
unsigned long flags);
extern void __iomem *ioremap_wc(phys_addr_t address, unsigned long size);
#define ioremap_nocache(addr, size) ioremap((addr), (size))
+#define ioremap_uc(addr, size) ioremap((addr), (size))
extern void iounmap(volatile void __iomem *addr);
diff --git a/arch/s390/include/asm/io.h b/arch/s390/include/asm/io.h
index cb5fdf3a78fc..437e9af96688 100644
--- a/arch/s390/include/asm/io.h
+++ b/arch/s390/include/asm/io.h
@@ -57,6 +57,8 @@ static inline void ioport_unmap(void __iomem *p)
*/
#define pci_iomap pci_iomap
#define pci_iounmap pci_iounmap
+#define pci_iomap_wc pci_iomap
+#define pci_iomap_wc_range pci_iomap_range
#define memcpy_fromio(dst, src, count) zpci_memcpy_fromio(dst, src, count)
#define memcpy_toio(dst, src, count) zpci_memcpy_toio(dst, src, count)
diff --git a/arch/sh/include/asm/io.h b/arch/sh/include/asm/io.h
index 728c4c571f40..93ec9066dbef 100644
--- a/arch/sh/include/asm/io.h
+++ b/arch/sh/include/asm/io.h
@@ -368,6 +368,7 @@ static inline int iounmap_fixed(void __iomem *addr) { return -EINVAL; }
#endif
#define ioremap_nocache ioremap
+#define ioremap_uc ioremap
#define iounmap __iounmap
/*
diff --git a/arch/tile/include/asm/io.h b/arch/tile/include/asm/io.h
index dc61de15c1f9..322b5fe94781 100644
--- a/arch/tile/include/asm/io.h
+++ b/arch/tile/include/asm/io.h
@@ -55,6 +55,7 @@ extern void iounmap(volatile void __iomem *addr);
#define ioremap_nocache(physaddr, size) ioremap(physaddr, size)
#define ioremap_wc(physaddr, size) ioremap(physaddr, size)
#define ioremap_wt(physaddr, size) ioremap(physaddr, size)
+#define ioremap_uc(physaddr, size) ioremap(physaddr, size)
#define ioremap_fullcache(physaddr, size) ioremap(physaddr, size)
#define mmiowb()
diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
index cc9c61bc1abe..7cfc085b6879 100644
--- a/arch/x86/include/asm/io.h
+++ b/arch/x86/include/asm/io.h
@@ -180,6 +180,8 @@ static inline unsigned int isa_virt_to_bus(volatile void *address)
*/
extern void __iomem *ioremap_nocache(resource_size_t offset, unsigned long size);
extern void __iomem *ioremap_uc(resource_size_t offset, unsigned long size);
+#define ioremap_uc ioremap_uc
+
extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size);
extern void __iomem *ioremap_prot(resource_size_t offset, unsigned long size,
unsigned long prot_val);
diff --git a/arch/x86/kernel/check.c b/arch/x86/kernel/check.c
index 58118e207a69..145863d4d343 100644
--- a/arch/x86/kernel/check.c
+++ b/arch/x86/kernel/check.c
@@ -1,4 +1,4 @@
-#include <linux/module.h>
+#include <linux/init.h>
#include <linux/sched.h>
#include <linux/kthread.h>
#include <linux/workqueue.h>
@@ -163,6 +163,5 @@ static int start_periodic_check_for_corruption(void)
schedule_delayed_work(&bios_check_work, 0);
return 0;
}
-
-module_init(start_periodic_check_for_corruption);
+device_initcall(start_periodic_check_for_corruption);
diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c
index e7ed0d8ebacb..f891b4750f04 100644
--- a/arch/x86/kernel/cpu/mtrr/main.c
+++ b/arch/x86/kernel/cpu/mtrr/main.c
@@ -448,7 +448,6 @@ int mtrr_add(unsigned long base, unsigned long size, unsigned int type,
return mtrr_add_page(base >> PAGE_SHIFT, size >> PAGE_SHIFT, type,
increment);
}
-EXPORT_SYMBOL(mtrr_add);
/**
* mtrr_del_page - delete a memory type region
@@ -537,7 +536,6 @@ int mtrr_del(int reg, unsigned long base, unsigned long size)
return -EINVAL;
return mtrr_del_page(reg, base >> PAGE_SHIFT, size >> PAGE_SHIFT);
}
-EXPORT_SYMBOL(mtrr_del);
/**
* arch_phys_wc_add - add a WC MTRR and handle errors if PAT is unavailable
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index 8533b46e6bee..1d8a83df153a 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -30,8 +30,11 @@
/*
* Tables translating between page_cache_type_t and pte encoding.
*
- * Minimal supported modes are defined statically, they are modified
- * during bootup if more supported cache modes are available.
+ * The default values are defined statically as minimal supported mode;
+ * WC and WT fall back to UC-. pat_init() updates these values to support
+ * more cache modes, WC and WT, when it is safe to do so. See pat_init()
+ * for the details. Note, __early_ioremap() used during early boot-time
+ * takes pgprot_t (pte encoding) and does not use these tables.
*
* Index into __cachemode2pte_tbl[] is the cachemode.
*
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 8340e45c891a..68aec42545c2 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -137,6 +137,7 @@ page_table_range_init_count(unsigned long start, unsigned long end)
vaddr = start;
pgd_idx = pgd_index(vaddr);
+ pmd_idx = pmd_index(vaddr);
for ( ; (pgd_idx < PTRS_PER_PGD) && (vaddr != end); pgd_idx++) {
for (; (pmd_idx < PTRS_PER_PMD) && (vaddr != end);
diff --git a/arch/x86/mm/pageattr-test.c b/arch/x86/mm/pageattr-test.c
index 8ff686aa7e8c..5f169d5d76a8 100644
--- a/arch/x86/mm/pageattr-test.c
+++ b/arch/x86/mm/pageattr-test.c
@@ -8,6 +8,7 @@
#include <linux/kthread.h>
#include <linux/random.h>
#include <linux/kernel.h>
+#include <linux/init.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>
@@ -256,5 +257,4 @@ static int start_pageattr_test(void)
return 0;
}
-
-module_init(start_pageattr_test);
+device_initcall(start_pageattr_test);
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 727158cb3b3c..2c44c0792301 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -4,7 +4,6 @@
*/
#include <linux/highmem.h>
#include <linux/bootmem.h>
-#include <linux/module.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
diff --git a/drivers/dma/iop-adma.c b/drivers/dma/iop-adma.c
index 998826854fdd..e4f43125e0fb 100644
--- a/drivers/dma/iop-adma.c
+++ b/drivers/dma/iop-adma.c
@@ -1300,10 +1300,11 @@ static int iop_adma_probe(struct platform_device *pdev)
* note: writecombine gives slightly better performance, but
* requires that we explicitly flush the writes
*/
- if ((adev->dma_desc_pool_virt = dma_alloc_writecombine(&pdev->dev,
- plat_data->pool_size,
- &adev->dma_desc_pool,
- GFP_KERNEL)) == NULL) {
+ adev->dma_desc_pool_virt = dma_alloc_writecombine(&pdev->dev,
+ plat_data->pool_size,
+ &adev->dma_desc_pool,
+ GFP_KERNEL);
+ if (!adev->dma_desc_pool_virt) {
ret = -ENOMEM;
goto err_free_adev;
}
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index cc76238c86fb..6a9a1116f1eb 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -138,6 +138,20 @@ void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar)
return ioremap_nocache(res->start, resource_size(res));
}
EXPORT_SYMBOL_GPL(pci_ioremap_bar);
+
+void __iomem *pci_ioremap_wc_bar(struct pci_dev *pdev, int bar)
+{
+ /*
+ * Make sure the BAR is actually a memory resource, not an IO resource
+ */
+ if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) {
+ WARN_ON(1);
+ return NULL;
+ }
+ return ioremap_wc(pci_resource_start(pdev, bar),
+ pci_resource_len(pdev, bar));
+}
+EXPORT_SYMBOL_GPL(pci_ioremap_wc_bar);
#endif
diff --git a/drivers/video/fbdev/arkfb.c b/drivers/video/fbdev/arkfb.c
index b305a1e7cc76..6a317de7082c 100644
--- a/drivers/video/fbdev/arkfb.c
+++ b/drivers/video/fbdev/arkfb.c
@@ -26,13 +26,9 @@
#include <linux/console.h> /* Why should fb driver call console functions? because console_lock() */
#include <video/vga.h>
-#ifdef CONFIG_MTRR
-#include <asm/mtrr.h>
-#endif
-
struct arkfb_info {
int mclk_freq;
- int mtrr_reg;
+ int wc_cookie;
struct dac_info *dac;
struct vgastate state;
@@ -102,10 +98,6 @@ static const struct svga_timing_regs ark_timing_regs = {
static char *mode_option = "640x480-8@60";
-#ifdef CONFIG_MTRR
-static int mtrr = 1;
-#endif
-
MODULE_AUTHOR("(c) 2007 Ondrej Zajicek <santiago@crfreenet.org>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("fbdev driver for ARK 2000PV");
@@ -115,11 +107,6 @@ MODULE_PARM_DESC(mode_option, "Default video mode ('640x480-8@60', etc)");
module_param_named(mode, mode_option, charp, 0444);
MODULE_PARM_DESC(mode, "Default video mode ('640x480-8@60', etc) (deprecated)");
-#ifdef CONFIG_MTRR
-module_param(mtrr, int, 0444);
-MODULE_PARM_DESC(mtrr, "Enable write-combining with MTRR (1=enable, 0=disable, default=1)");
-#endif
-
static int threshold = 4;
module_param(threshold, int, 0644);
@@ -1002,7 +989,7 @@ static int ark_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
info->fix.smem_len = pci_resource_len(dev, 0);
/* Map physical IO memory address into kernel space */
- info->screen_base = pci_iomap(dev, 0, 0);
+ info->screen_base = pci_iomap_wc(dev, 0, 0);
if (! info->screen_base) {
rc = -ENOMEM;
dev_err(info->device, "iomap for framebuffer failed\n");
@@ -1057,14 +1044,8 @@ static int ark_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
/* Record a reference to the driver data */
pci_set_drvdata(dev, info);
-
-#ifdef CONFIG_MTRR
- if (mtrr) {
- par->mtrr_reg = -1;
- par->mtrr_reg = mtrr_add(info->fix.smem_start, info->fix.smem_len, MTRR_TYPE_WRCOMB, 1);
- }
-#endif
-
+ par->wc_cookie = arch_phys_wc_add(info->fix.smem_start,
+ info->fix.smem_len);
return 0;
/* Error handling */
@@ -1092,14 +1073,7 @@ static void ark_pci_remove(struct pci_dev *dev)
if (info) {
struct arkfb_info *par = info->par;
-
-#ifdef CONFIG_MTRR
- if (par->mtrr_reg >= 0) {
- mtrr_del(par->mtrr_reg, 0, 0);
- par->mtrr_reg = -1;
- }
-#endif
-
+ arch_phys_wc_del(par->wc_cookie);
dac_release(par->dac);
unregister_framebuffer(info);
fb_dealloc_cmap(&info->cmap);
diff --git a/drivers/video/fbdev/aty/atyfb.h b/drivers/video/fbdev/aty/atyfb.h
index 1f39a62f899b..63c4842eb224 100644
--- a/drivers/video/fbdev/aty/atyfb.h
+++ b/drivers/video/fbdev/aty/atyfb.h
@@ -182,10 +182,7 @@ struct atyfb_par {
unsigned long irq_flags;
unsigned int irq;
spinlock_t int_lock;
-#ifdef CONFIG_MTRR
- int mtrr_aper;
- int mtrr_reg;
-#endif
+ int wc_cookie;
u32 mem_cntl;
struct crtc saved_crtc;
union aty_pll saved_pll;
diff --git a/drivers/video/fbdev/aty/atyfb_base.c b/drivers/video/fbdev/aty/atyfb_base.c
index 8789e487b96e..f34ed47fcaf8 100644
--- a/drivers/video/fbdev/aty/atyfb_base.c
+++ b/drivers/video/fbdev/aty/atyfb_base.c
@@ -98,9 +98,6 @@
#ifdef CONFIG_PMAC_BACKLIGHT
#include <asm/backlight.h>
#endif
-#ifdef CONFIG_MTRR
-#include <asm/mtrr.h>
-#endif
/*
* Debug flags.
@@ -303,9 +300,7 @@ static struct fb_ops atyfb_ops = {
};
static bool noaccel;
-#ifdef CONFIG_MTRR
static bool nomtrr;
-#endif
static int vram;
static int pll;
static int mclk;
@@ -427,6 +422,20 @@ static struct {
#endif /* CONFIG_FB_ATY_CT */
};
+/*
+ * Last page of 8 MB (4 MB on ISA) aperture is MMIO,
+ * unless the auxiliary register aperture is used.
+ */
+static void aty_fudge_framebuffer_len(struct fb_info *info)
+{
+ struct atyfb_par *par = (struct atyfb_par *) info->par;
+
+ if (!par->aux_start &&
+ (info->fix.smem_len == 0x800000 ||
+ (par->bus_type == ISA && info->fix.smem_len == 0x400000)))
+ info->fix.smem_len -= GUI_RESERVE;
+}
+
static int correct_chipset(struct atyfb_par *par)
{
u8 rev;
@@ -2603,14 +2612,7 @@ static int aty_init(struct fb_info *info)
if (par->pll_ops->resume_pll)
par->pll_ops->resume_pll(info, &par->pll);
- /*
- * Last page of 8 MB (4 MB on ISA) aperture is MMIO,
- * unless the auxiliary register aperture is used.
- */
- if (!par->aux_start &&
- (info->fix.smem_len == 0x800000 ||
- (par->bus_type == ISA && info->fix.smem_len == 0x400000)))
- info->fix.smem_len -= GUI_RESERVE;
+ aty_fudge_framebuffer_len(info);
/*
* Disable register access through the linear aperture
@@ -2621,25 +2623,13 @@ static int aty_init(struct fb_info *info)
aty_st_le32(BUS_CNTL, aty_ld_le32(BUS_CNTL, par) |
BUS_APER_REG_DIS, par);
-#ifdef CONFIG_MTRR
- par->mtrr_aper = -1;
- par->mtrr_reg = -1;
- if (!nomtrr) {
- /* Cover the whole resource. */
- par->mtrr_aper = mtrr_add(par->res_start, par->res_size,
- MTRR_TYPE_WRCOMB, 1);
- if (par->mtrr_aper >= 0 && !par->aux_start) {
- /* Make a hole for mmio. */
- par->mtrr_reg = mtrr_add(par->res_start + 0x800000 -
- GUI_RESERVE, GUI_RESERVE,
- MTRR_TYPE_UNCACHABLE, 1);
- if (par->mtrr_reg < 0) {
- mtrr_del(par->mtrr_aper, 0, 0);
- par->mtrr_aper = -1;
- }
- }
- }
-#endif
+ if (!nomtrr)
+ /*
+ * Only the ioremap_wc()'d area will get WC here
+ * since ioremap_uc() was used on the entire PCI BAR.
+ */
+ par->wc_cookie = arch_phys_wc_add(par->res_start,
+ par->res_size);
info->fbops = &atyfb_ops;
info->pseudo_palette = par->pseudo_palette;
@@ -2767,17 +2757,8 @@ aty_init_exit:
/* restore video mode */
aty_set_crtc(par, &par->saved_crtc);
par->pll_ops->set_pll(info, &par->saved_pll);
+ arch_phys_wc_del(par->wc_cookie);
-#ifdef CONFIG_MTRR
- if (par->mtrr_reg >= 0) {
- mtrr_del(par->mtrr_reg, 0, 0);
- par->mtrr_reg = -1;
- }
- if (par->mtrr_aper >= 0) {
- mtrr_del(par->mtrr_aper, 0, 0);
- par->mtrr_aper = -1;
- }
-#endif
return ret;
}
@@ -3459,7 +3440,11 @@ static int atyfb_setup_generic(struct pci_dev *pdev, struct fb_info *info,
}
info->fix.mmio_start = raddr;
- par->ati_regbase = ioremap(info->fix.mmio_start, 0x1000);
+ /*
+ * By using strong UC we force the MTRR to never have an
+ * effect on the MMIO region on both non-PAT and PAT systems.
+ */
+ par->ati_regbase = ioremap_uc(info->fix.mmio_start, 0x1000);
if (par->ati_regbase == NULL)
return -ENOMEM;
@@ -3482,7 +3467,24 @@ static int atyfb_setup_generic(struct pci_dev *pdev, struct fb_info *info,
/* Map in frame buffer */
info->fix.smem_start = addr;
- info->screen_base = ioremap(addr, 0x800000);
+
+ /*
+ * The framebuffer is not always 8 MiB, that's just the size of the
+ * PCI BAR. We temporarily abuse smem_len here to store the size
+ * of the BAR. aty_init() will later correct it to match the actual
+ * framebuffer size.
+ *
+ * On devices that don't have the auxiliary register aperture, the
+ * registers are housed at the top end of the framebuffer PCI BAR.
+ * aty_fudge_framebuffer_len() is used to reduce smem_len to not
+ * overlap with the registers.
+ */
+ info->fix.smem_len = 0x800000;
+
+ aty_fudge_framebuffer_len(info);
+
+ info->screen_base = ioremap_wc(info->fix.smem_start,
+ info->fix.smem_len);
if (info->screen_base == NULL) {
ret = -ENOMEM;
goto atyfb_setup_generic_fail;
@@ -3554,6 +3556,7 @@ static int atyfb_pci_probe(struct pci_dev *pdev,
return -ENOMEM;
}
par = info->par;
+ par->bus_type = PCI;
info->fix = atyfb_fix;
info->device = &pdev->dev;
par->pci_id = pdev->device;
@@ -3655,7 +3658,8 @@ static int __init atyfb_atari_probe(void)
* Map the video memory (physical address given)
* to somewhere in the kernel address space.
*/
- info->screen_base = ioremap(phys_vmembase[m64_num], phys_size[m64_num]);
+ info->screen_base = ioremap_wc(phys_vmembase[m64_num],
+ phys_size[m64_num]);
info->fix.smem_start = (unsigned long)info->screen_base; /* Fake! */
par->ati_regbase = ioremap(phys_guiregbase[m64_num], 0x10000) +
0xFC00ul;
@@ -3721,17 +3725,8 @@ static void atyfb_remove(struct fb_info *info)
if (M64_HAS(MOBIL_BUS))
aty_bl_exit(info->bl_dev);
#endif
+ arch_phys_wc_del(par->wc_cookie);
-#ifdef CONFIG_MTRR
- if (par->mtrr_reg >= 0) {
- mtrr_del(par->mtrr_reg, 0, 0);
- par->mtrr_reg = -1;
- }
- if (par->mtrr_aper >= 0) {
- mtrr_del(par->mtrr_aper, 0, 0);
- par->mtrr_aper = -1;
- }
-#endif
#ifndef __sparc__
if (par->ati_regbase)
iounmap(par->ati_regbase);
@@ -3847,10 +3842,8 @@ static int __init atyfb_setup(char *options)
while ((this_opt = strsep(&options, ",")) != NULL) {
if (!strncmp(this_opt, "noaccel", 7)) {
noaccel = 1;
-#ifdef CONFIG_MTRR
} else if (!strncmp(this_opt, "nomtrr", 6)) {
nomtrr = 1;
-#endif
} else if (!strncmp(this_opt, "vram:", 5))
vram = simple_strtoul(this_opt + 5, NULL, 0);
else if (!strncmp(this_opt, "pll:", 4))
@@ -4020,7 +4013,5 @@ module_param(comp_sync, int, 0);
MODULE_PARM_DESC(comp_sync, "Set composite sync signal to low (0) or high (1)");
module_param(mode, charp, 0);
MODULE_PARM_DESC(mode, "Specify resolution as \"<xres>x<yres>[-<bpp>][@<refresh>]\" ");
-#ifdef CONFIG_MTRR
module_param(nomtrr, bool, 0);
MODULE_PARM_DESC(nomtrr, "bool: disable use of MTRR registers");
-#endif
diff --git a/drivers/video/fbdev/gxt4500.c b/drivers/video/fbdev/gxt4500.c
index 135d78a02588..f19133a80e8c 100644
--- a/drivers/video/fbdev/gxt4500.c
+++ b/drivers/video/fbdev/gxt4500.c
@@ -662,7 +662,7 @@ static int gxt4500_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
info->fix.smem_start = fb_phys;
info->fix.smem_len = pci_resource_len(pdev, 1);
- info->screen_base = pci_ioremap_bar(pdev, 1);
+ info->screen_base = pci_ioremap_wc_bar(pdev, 1);
if (!info->screen_base) {
dev_err(&pdev->dev, "gxt4500: cannot map framebuffer\n");
goto err_unmap_regs;
diff --git a/drivers/video/fbdev/i740fb.c b/drivers/video/fbdev/i740fb.c
index a2b4204b42bb..452e1163ad02 100644
--- a/drivers/video/fbdev/i740fb.c
+++ b/drivers/video/fbdev/i740fb.c
@@ -27,24 +27,15 @@
#include <linux/console.h>
#include <video/vga.h>
-#ifdef CONFIG_MTRR
-#include <asm/mtrr.h>
-#endif
-
#include "i740_reg.h"
static char *mode_option;
-
-#ifdef CONFIG_MTRR
static int mtrr = 1;
-#endif
struct i740fb_par {
unsigned char __iomem *regs;
bool has_sgram;
-#ifdef CONFIG_MTRR
- int mtrr_reg;
-#endif
+ int wc_cookie;
bool ddc_registered;
struct i2c_adapter ddc_adapter;
struct i2c_algo_bit_data ddc_algo;
@@ -1040,7 +1031,7 @@ static int i740fb_probe(struct pci_dev *dev, const struct pci_device_id *ent)
goto err_request_regions;
}
- info->screen_base = pci_ioremap_bar(dev, 0);
+ info->screen_base = pci_ioremap_wc_bar(dev, 0);
if (!info->screen_base) {
dev_err(info->device, "error remapping base\n");
ret = -ENOMEM;
@@ -1144,13 +1135,9 @@ static int i740fb_probe(struct pci_dev *dev, const struct pci_device_id *ent)
fb_info(info, "%s frame buffer device\n", info->fix.id);
pci_set_drvdata(dev, info);
-#ifdef CONFIG_MTRR
- if (mtrr) {
- par->mtrr_reg = -1;
- par->mtrr_reg = mtrr_add(info->fix.smem_start,
- info->fix.smem_len, MTRR_TYPE_WRCOMB, 1);
- }
-#endif
+ if (mtrr)
+ par->wc_cookie = arch_phys_wc_add(info->fix.smem_start,
+ info->fix.smem_len);
return 0;
err_reg_framebuffer:
@@ -1177,13 +1164,7 @@ static void i740fb_remove(struct pci_dev *dev)
if (info) {
struct i740fb_par *par = info->par;
-
-#ifdef CONFIG_MTRR
- if (par->mtrr_reg >= 0) {
- mtrr_del(par->mtrr_reg, 0, 0);
- par->mtrr_reg = -1;
- }
-#endif
+ arch_phys_wc_del(par->wc_cookie);
unregister_framebuffer(info);
fb_dealloc_cmap(&info->cmap);
if (par->ddc_registered)
@@ -1287,10 +1268,8 @@ static int __init i740fb_setup(char *options)
while ((opt = strsep(&options, ",")) != NULL) {
if (!*opt)
continue;
-#ifdef CONFIG_MTRR
else if (!strncmp(opt, "mtrr:", 5))
mtrr = simple_strtoul(opt + 5, NULL, 0);
-#endif
else
mode_option = opt;
}
@@ -1327,7 +1306,5 @@ MODULE_DESCRIPTION("fbdev driver for Intel740");
module_param(mode_option, charp, 0444);
MODULE_PARM_DESC(mode_option, "Default video mode ('640x480-8@60', etc)");
-#ifdef CONFIG_MTRR
module_param(mtrr, int, 0444);
MODULE_PARM_DESC(mtrr, "Enable write-combining with MTRR (1=enable, 0=disable, default=1)");
-#endif
diff --git a/drivers/video/fbdev/kyro/fbdev.c b/drivers/video/fbdev/kyro/fbdev.c
index 65041e15fd59..5bb01533271e 100644
--- a/drivers/video/fbdev/kyro/fbdev.c
+++ b/drivers/video/fbdev/kyro/fbdev.c
@@ -22,9 +22,6 @@
#include <linux/pci.h>
#include <asm/io.h>
#include <linux/uaccess.h>
-#ifdef CONFIG_MTRR
-#include <asm/mtrr.h>
-#endif
#include <video/kyro.h>
@@ -84,9 +81,7 @@ static device_info_t deviceInfo;
static char *mode_option = NULL;
static int nopan = 0;
static int nowrap = 1;
-#ifdef CONFIG_MTRR
static int nomtrr = 0;
-#endif
/* PCI driver prototypes */
static int kyrofb_probe(struct pci_dev *pdev, const struct pci_device_id *ent);
@@ -570,10 +565,8 @@ static int __init kyrofb_setup(char *options)
nopan = 1;
} else if (strcmp(this_opt, "nowrap") == 0) {
nowrap = 1;
-#ifdef CONFIG_MTRR
} else if (strcmp(this_opt, "nomtrr") == 0) {
nomtrr = 1;
-#endif
} else {
mode_option = this_opt;
}
@@ -691,17 +684,16 @@ static int kyrofb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
currentpar->regbase = deviceInfo.pSTGReg =
ioremap_nocache(kyro_fix.mmio_start, kyro_fix.mmio_len);
+ if (!currentpar->regbase)
+ goto out_free_fb;
- info->screen_base = ioremap_nocache(kyro_fix.smem_start,
- kyro_fix.smem_len);
+ info->screen_base = pci_ioremap_wc_bar(pdev, 0);
+ if (!info->screen_base)
+ goto out_unmap_regs;
-#ifdef CONFIG_MTRR
if (!nomtrr)
- currentpar->mtrr_handle =
- mtrr_add(kyro_fix.smem_start,
- kyro_fix.smem_len,
- MTRR_TYPE_WRCOMB, 1);
-#endif
+ currentpar->wc_cookie = arch_phys_wc_add(kyro_fix.smem_start,
+ kyro_fix.smem_len);
kyro_fix.ypanstep = nopan ? 0 : 1;
kyro_fix.ywrapstep = nowrap ? 0 : 1;
@@ -745,8 +737,10 @@ static int kyrofb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
return 0;
out_unmap:
- iounmap(currentpar->regbase);
iounmap(info->screen_base);
+out_unmap_regs:
+ iounmap(currentpar->regbase);
+out_free_fb:
framebuffer_release(info);
return -EINVAL;
@@ -770,12 +764,7 @@ static void kyrofb_remove(struct pci_dev *pdev)
iounmap(info->screen_base);
iounmap(par->regbase);
-#ifdef CONFIG_MTRR
- if (par->mtrr_handle)
- mtrr_del(par->mtrr_handle,
- info->fix.smem_start,
- info->fix.smem_len);
-#endif
+ arch_phys_wc_del(par->wc_cookie);
unregister_framebuffer(info);
framebuffer_release(info);
diff --git a/drivers/video/fbdev/s3fb.c b/drivers/video/fbdev/s3fb.c
index f0ae61a37f04..13b109073c63 100644
--- a/drivers/video/fbdev/s3fb.c
+++ b/drivers/video/fbdev/s3fb.c
@@ -28,13 +28,9 @@
#include <linux/i2c.h>
#include <linux/i2c-algo-bit.h>
-#ifdef CONFIG_MTRR
-#include <asm/mtrr.h>
-#endif
-
struct s3fb_info {
int chip, rev, mclk_freq;
- int mtrr_reg;
+ int wc_cookie;
struct vgastate state;
struct mutex open_lock;
unsigned int ref_count;
@@ -154,11 +150,7 @@ static const struct svga_timing_regs s3_timing_regs = {
static char *mode_option;
-
-#ifdef CONFIG_MTRR
static int mtrr = 1;
-#endif
-
static int fasttext = 1;
@@ -170,11 +162,8 @@ module_param(mode_option, charp, 0444);
MODULE_PARM_DESC(mode_option, "Default video mode ('640x480-8@60', etc)");
module_param_named(mode, mode_option, charp, 0444);
MODULE_PARM_DESC(mode, "Default video mode ('640x480-8@60', etc) (deprecated)");
-
-#ifdef CONFIG_MTRR
module_param(mtrr, int, 0444);
MODULE_PARM_DESC(mtrr, "Enable write-combining with MTRR (1=enable, 0=disable, default=1)");
-#endif
module_param(fasttext, int, 0644);
MODULE_PARM_DESC(fasttext, "Enable S3 fast text mode (1=enable, 0=disable, default=1)");
@@ -1168,7 +1157,7 @@ static int s3_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
info->fix.smem_len = pci_resource_len(dev, 0);
/* Map physical IO memory address into kernel space */
- info->screen_base = pci_iomap(dev, 0, 0);
+ info->screen_base = pci_iomap_wc(dev, 0, 0);
if (! info->screen_base) {
rc = -ENOMEM;
dev_err(info->device, "iomap for framebuffer failed\n");
@@ -1365,12 +1354,9 @@ static int s3_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
/* Record a reference to the driver data */
pci_set_drvdata(dev, info);
-#ifdef CONFIG_MTRR
- if (mtrr) {
- par->mtrr_reg = -1;
- par->mtrr_reg = mtrr_add(info->fix.smem_start, info->fix.smem_len, MTRR_TYPE_WRCOMB, 1);
- }
-#endif
+ if (mtrr)
+ par->wc_cookie = arch_phys_wc_add(info->fix.smem_start,
+ info->fix.smem_len);
return 0;
@@ -1405,14 +1391,7 @@ static void s3_pci_remove(struct pci_dev *dev)
if (info) {
par = info->par;
-
-#ifdef CONFIG_MTRR
- if (par->mtrr_reg >= 0) {
- mtrr_del(par->mtrr_reg, 0, 0);
- par->mtrr_reg = -1;
- }
-#endif
-
+ arch_phys_wc_del(par->wc_cookie);
unregister_framebuffer(info);
fb_dealloc_cmap(&info->cmap);
@@ -1551,10 +1530,8 @@ static int __init s3fb_setup(char *options)
if (!*opt)
continue;
-#ifdef CONFIG_MTRR
else if (!strncmp(opt, "mtrr:", 5))
mtrr = simple_strtoul(opt + 5, NULL, 0);
-#endif
else if (!strncmp(opt, "fasttext:", 9))
fasttext = simple_strtoul(opt + 9, NULL, 0);
else
diff --git a/drivers/video/fbdev/vt8623fb.c b/drivers/video/fbdev/vt8623fb.c
index 8bac309c24b9..dd0f18e42d3e 100644
--- a/drivers/video/fbdev/vt8623fb.c
+++ b/drivers/video/fbdev/vt8623fb.c
@@ -26,13 +26,9 @@
#include <linux/console.h> /* Why should fb driver call console functions? because console_lock() */
#include <video/vga.h>
-#ifdef CONFIG_MTRR
-#include <asm/mtrr.h>
-#endif
-
struct vt8623fb_info {
char __iomem *mmio_base;
- int mtrr_reg;
+ int wc_cookie;
struct vgastate state;
struct mutex open_lock;
unsigned int ref_count;
@@ -99,10 +95,7 @@ static struct svga_timing_regs vt8623_timing_regs = {
/* Module parameters */
static char *mode_option = "640x480-8@60";
-
-#ifdef CONFIG_MTRR
static int mtrr = 1;
-#endif
MODULE_AUTHOR("(c) 2006 Ondrej Zajicek <santiago@crfreenet.org>");
MODULE_LICENSE("GPL");
@@ -112,11 +105,8 @@ module_param(mode_option, charp, 0644);
MODULE_PARM_DESC(mode_option, "Default video mode ('640x480-8@60', etc)");
module_param_named(mode, mode_option, charp, 0);
MODULE_PARM_DESC(mode, "Default video mode e.g. '648x480-8@60' (deprecated)");
-
-#ifdef CONFIG_MTRR
module_param(mtrr, int, 0444);
MODULE_PARM_DESC(mtrr, "Enable write-combining with MTRR (1=enable, 0=disable, default=1)");
-#endif
/* ------------------------------------------------------------------------- */
@@ -710,7 +700,7 @@ static int vt8623_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
info->fix.mmio_len = pci_resource_len(dev, 1);
/* Map physical IO memory address into kernel space */
- info->screen_base = pci_iomap(dev, 0, 0);
+ info->screen_base = pci_iomap_wc(dev, 0, 0);
if (! info->screen_base) {
rc = -ENOMEM;
dev_err(info->device, "iomap for framebuffer failed\n");
@@ -781,12 +771,9 @@ static int vt8623_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
/* Record a reference to the driver data */
pci_set_drvdata(dev, info);
-#ifdef CONFIG_MTRR
- if (mtrr) {
- par->mtrr_reg = -1;
- par->mtrr_reg = mtrr_add(info->fix.smem_start, info->fix.smem_len, MTRR_TYPE_WRCOMB, 1);
- }
-#endif
+ if (mtrr)
+ par->wc_cookie = arch_phys_wc_add(info->fix.smem_start,
+ info->fix.smem_len);
return 0;
@@ -816,13 +803,7 @@ static void vt8623_pci_remove(struct pci_dev *dev)
if (info) {
struct vt8623fb_info *par = info->par;
-#ifdef CONFIG_MTRR
- if (par->mtrr_reg >= 0) {
- mtrr_del(par->mtrr_reg, 0, 0);
- par->mtrr_reg = -1;
- }
-#endif
-
+ arch_phys_wc_del(par->wc_cookie);
unregister_framebuffer(info);
fb_dealloc_cmap(&info->cmap);
diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
index f56094cfdeff..eed3bbe88c8a 100644
--- a/include/asm-generic/io.h
+++ b/include/asm-generic/io.h
@@ -736,6 +736,35 @@ static inline void *phys_to_virt(unsigned long address)
}
#endif
+/**
+ * DOC: ioremap() and ioremap_*() variants
+ *
+ * If you have an IOMMU your architecture is expected to have both ioremap()
+ * and iounmap() implemented otherwise the asm-generic helpers will provide a
+ * direct mapping.
+ *
+ * There are ioremap_*() call variants, if you have no IOMMU we naturally will
+ * default to direct mapping for all of them, you can override these defaults.
+ * If you have an IOMMU you are highly encouraged to provide your own
+ * ioremap variant implementation as there currently is no safe architecture
+ * agnostic default. To avoid possible improper behaviour default asm-generic
+ * ioremap_*() variants all return NULL when an IOMMU is available. If you've
+ * defined your own ioremap_*() variant you must then declare your own
+ * ioremap_*() variant as defined to itself to avoid the default NULL return.
+ */
+
+#ifdef CONFIG_MMU
+
+#ifndef ioremap_uc
+#define ioremap_uc ioremap_uc
+static inline void __iomem *ioremap_uc(phys_addr_t offset, size_t size)
+{
+ return NULL;
+}
+#endif
+
+#else /* !CONFIG_MMU */
+
/*
* Change "struct page" to physical address.
*
@@ -743,7 +772,6 @@ static inline void *phys_to_virt(unsigned long address)
* you'll need to provide your own definitions.
*/
-#ifndef CONFIG_MMU
#ifndef ioremap
#define ioremap ioremap
static inline void __iomem *ioremap(phys_addr_t offset, size_t size)
diff --git a/include/asm-generic/pci_iomap.h b/include/asm-generic/pci_iomap.h
index 7389c87116a0..b1e17fcee2d0 100644
--- a/include/asm-generic/pci_iomap.h
+++ b/include/asm-generic/pci_iomap.h
@@ -15,9 +15,13 @@ struct pci_dev;
#ifdef CONFIG_PCI
/* Create a virtual mapping cookie for a PCI BAR (memory or IO) */
extern void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long max);
+extern void __iomem *pci_iomap_wc(struct pci_dev *dev, int bar, unsigned long max);
extern void __iomem *pci_iomap_range(struct pci_dev *dev, int bar,
unsigned long offset,
unsigned long maxlen);
+extern void __iomem *pci_iomap_wc_range(struct pci_dev *dev, int bar,
+ unsigned long offset,
+ unsigned long maxlen);
/* Create a virtual mapping cookie for a port on a given PCI device.
* Do not call this directly, it exists to make it easier for architectures
* to override */
@@ -34,12 +38,22 @@ static inline void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned lon
return NULL;
}
+static inline void __iomem *pci_iomap_wc(struct pci_dev *dev, int bar, unsigned long max)
+{
+ return NULL;
+}
static inline void __iomem *pci_iomap_range(struct pci_dev *dev, int bar,
unsigned long offset,
unsigned long maxlen)
{
return NULL;
}
+static inline void __iomem *pci_iomap_wc_range(struct pci_dev *dev, int bar,
+ unsigned long offset,
+ unsigned long maxlen)
+{
+ return NULL;
+}
#endif
#endif /* __ASM_GENERIC_IO_H */
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 3c8eb57de620..4fee9cd7a7df 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1710,6 +1710,7 @@ static inline void pci_mmcfg_late_init(void) { }
int pci_ext_cfg_avail(void);
void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar);
+void __iomem *pci_ioremap_wc_bar(struct pci_dev *pdev, int bar);
#ifdef CONFIG_PCI_IOV
int pci_iov_virtfn_bus(struct pci_dev *dev, int id);
diff --git a/include/video/kyro.h b/include/video/kyro.h
index c563968e926c..b958c2e9c915 100644
--- a/include/video/kyro.h
+++ b/include/video/kyro.h
@@ -35,9 +35,7 @@ struct kyrofb_info {
/* Useful to hold depth here for Linux */
u8 PIXDEPTH;
-#ifdef CONFIG_MTRR
- int mtrr_handle;
-#endif
+ int wc_cookie;
};
extern int kyro_dev_init(void);
diff --git a/lib/pci_iomap.c b/lib/pci_iomap.c
index bcce5f149310..5f5d24d1d53f 100644
--- a/lib/pci_iomap.c
+++ b/lib/pci_iomap.c
@@ -52,6 +52,51 @@ void __iomem *pci_iomap_range(struct pci_dev *dev,
EXPORT_SYMBOL(pci_iomap_range);
/**
+ * pci_iomap_wc_range - create a virtual WC mapping cookie for a PCI BAR
+ * @dev: PCI device that owns the BAR
+ * @bar: BAR number
+ * @offset: map memory at the given offset in BAR
+ * @maxlen: max length of the memory to map
+ *
+ * Using this function you will get a __iomem address to your device BAR.
+ * You can access it using ioread*() and iowrite*(). These functions hide
+ * the details if this is a MMIO or PIO address space and will just do what
+ * you expect from them in the correct way. When possible write combining
+ * is used.
+ *
+ * @maxlen specifies the maximum length to map. If you want to get access to
+ * the complete BAR from offset to the end, pass %0 here.
+ * */
+void __iomem *pci_iomap_wc_range(struct pci_dev *dev,
+ int bar,
+ unsigned long offset,
+ unsigned long maxlen)
+{
+ resource_size_t start = pci_resource_start(dev, bar);
+ resource_size_t len = pci_resource_len(dev, bar);
+ unsigned long flags = pci_resource_flags(dev, bar);
+
+
+ if (flags & IORESOURCE_IO)
+ return NULL;
+
+ if (len <= offset || !start)
+ return NULL;
+
+ len -= offset;
+ start += offset;
+ if (maxlen && len > maxlen)
+ len = maxlen;
+
+ if (flags & IORESOURCE_MEM)
+ return ioremap_wc(start, len);
+
+ /* What? */
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(pci_iomap_wc_range);
+
+/**
* pci_iomap - create a virtual mapping cookie for a PCI BAR
* @dev: PCI device that owns the BAR
* @bar: BAR number
@@ -70,4 +115,25 @@ void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)
return pci_iomap_range(dev, bar, 0, maxlen);
}
EXPORT_SYMBOL(pci_iomap);
+
+/**
+ * pci_iomap_wc - create a virtual WC mapping cookie for a PCI BAR
+ * @dev: PCI device that owns the BAR
+ * @bar: BAR number
+ * @maxlen: length of the memory to map
+ *
+ * Using this function you will get a __iomem address to your device BAR.
+ * You can access it using ioread*() and iowrite*(). These functions hide
+ * the details if this is a MMIO or PIO address space and will just do what
+ * you expect from them in the correct way. When possible write combining
+ * is used.
+ *
+ * @maxlen specifies the maximum length to map. If you want to get access to
+ * the complete BAR without checking for its length first, pass %0 here.
+ * */
+void __iomem *pci_iomap_wc(struct pci_dev *dev, int bar, unsigned long maxlen)
+{
+ return pci_iomap_wc_range(dev, bar, 0, maxlen);
+}
+EXPORT_SYMBOL_GPL(pci_iomap_wc);
#endif /* CONFIG_PCI */