From: Wu Zhangjin <wuzj@xxxxxxxxxx>
The main purpose is to uncache accelerate for video memory access
Signed-off-by: Wu Zhangjin <wuzhangjin@xxxxxxxxx>
---
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 */
--
1.6.0.4
