[Gnewsense-dev] [loongson-PATCH-v1 17/27] define Loongson2F arch specific phys prot access

[wuzhangjin]

From: Wu Zhangjin <address@hidden>

The main purpose is to uncache accelerate for video memory access

Signed-off-by: Wu Zhangjin <address@hidden>
---
 arch/mips/include/asm/pgtable.h |   13 ++++++++
 arch/mips/loongson/Kconfig      |   12 +++++++
 arch/mips/loongson/common/mem.c |   63 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 88 insertions(+), 0 deletions(-)

diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
index 6a0edf7..fdb32a5 100644
--- a/arch/mips/include/asm/pgtable.h
+++ b/arch/mips/include/asm/pgtable.h
@@ -370,6 +370,19 @@ static inline int io_remap_pfn_range(struct vm_area_struct 
*vma,
 #include <asm-generic/pgtable.h>
 
 /*
+ * uncache accelerate for video memory access
+ */
+#ifdef CONFIG_LOONGSON2F
+#define __HAVE_PHYS_MEM_ACCESS_PROT
+
+struct file;
+pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
+               unsigned long size, pgprot_t vma_prot);
+int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
+               unsigned long size, pgprot_t *vma_prot);
+#endif
+
+/*
  * We provide our own get_unmapped area to cope with the virtual aliasing
  * constraints placed on us by the cache architecture.
  */
diff --git a/arch/mips/loongson/Kconfig b/arch/mips/loongson/Kconfig
index 9cc817f..3d582cb 100644
--- a/arch/mips/loongson/Kconfig
+++ b/arch/mips/loongson/Kconfig
@@ -114,3 +114,15 @@ config CS5536_UDC
 
 config SYS_HAS_MACH_PROM_INIT_CMDLINE
        bool
+
+config UCA_SIZE
+       hex "Uncache Accelerated Region size"
+       depends on CPU_LOONGSON2F
+       default 0x400000 if LEMOTE_YEELOONG2F
+       default 0x2000000 if LEMOTE_FULOONG2F
+       help
+         Uncached Acceleration(UCA) can greatly improve video performance.
+         Normally the Video memory can be accessed in Uncached Accelerated 
mode,
+         other peripheral spaces not.
+
+         Specify a zeroed size to disable this feature.
diff --git a/arch/mips/loongson/common/mem.c b/arch/mips/loongson/common/mem.c
index 9e0b6e0..7223d82 100644
--- a/arch/mips/loongson/common/mem.c
+++ b/arch/mips/loongson/common/mem.c
@@ -51,3 +51,66 @@ int __uncached_access(struct file *file, unsigned long addr)
                ((addr >= LOONGSON_MMIO_MEM_START) && \
                        (addr < LOONGSON_MMIO_MEM_END));
 }
+
+#if defined(CONFIG_CPU_LOONGSON2F)
+
+#include <linux/pci.h>
+#include <linux/sched.h>
+#include <asm/current.h>
+
+static unsigned long uca_start;
+static unsigned long uca_size = CONFIG_UCA_SIZE;
+
+pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
+                                    unsigned long size, pgprot_t vma_prot)
+{
+       unsigned long offset = pfn << PAGE_SHIFT;
+       unsigned long end = offset + size;
+
+       if (__uncached_access(file, offset)) {
+               if (((uca_start && offset) >= uca_start) && \
+                               (end <= (uca_start + uca_size)))
+                       return __pgprot((pgprot_val(vma_prot) & \
+                                               ~_CACHE_MASK) | \
+                                       _CACHE_UNCACHED_ACCELERATED);
+               else
+                       return pgprot_noncached(vma_prot);
+       }
+       return vma_prot;
+}
+
+static int __init find_vga_mem_init(void)
+{
+       struct pci_dev *dev = 0;
+       struct resource *r;
+       int idx;
+
+       if (uca_start)
+               return 0;
+
+       for_each_pci_dev(dev) {
+               if ((dev->class >> 8) == PCI_CLASS_DISPLAY_VGA) {
+                       for (idx = 0; idx < PCI_NUM_RESOURCES; idx++) {
+                               r = &dev->resource[idx];
+                               if (!r->start && r->end)
+                                       continue;
+                               if (r->flags & IORESOURCE_IO)
+                                       continue;
+                               if (r->flags & IORESOURCE_MEM) {
+                                       uca_start = r->start;
+
+                                       printk(KERN_INFO
+                                       "find the frame buffer:start=%lx\n",
+                                       uca_start);
+
+                                       return 0;
+                               }
+                       }
+
+               }
+       }
+       return 0;
+}
+
+late_initcall(find_vga_mem_init);
+#endif /* !CONFIG_CPU_LOONGSON2F */
-- 
1.6.2.1