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Diffstat (limited to 'arch/powerpc/mm/fsl_booke_mmu.c')
-rw-r--r--arch/powerpc/mm/fsl_booke_mmu.c43
1 files changed, 25 insertions, 18 deletions
diff --git a/arch/powerpc/mm/fsl_booke_mmu.c b/arch/powerpc/mm/fsl_booke_mmu.c
index f7802c8bba0..66a6fd38e9c 100644
--- a/arch/powerpc/mm/fsl_booke_mmu.c
+++ b/arch/powerpc/mm/fsl_booke_mmu.c
@@ -101,17 +101,17 @@ unsigned long p_mapped_by_tlbcam(phys_addr_t pa)
/*
* Set up a variable-size TLB entry (tlbcam). The parameters are not checked;
- * in particular size must be a power of 4 between 4k and 256M (or 1G, for cpus
- * that support extended page sizes). Note that while some cpus support a
- * page size of 4G, we don't allow its use here.
+ * in particular size must be a power of 4 between 4k and the max supported by
+ * an implementation; max may further be limited by what can be represented in
+ * an unsigned long (for example, 32-bit implementations cannot support a 4GB
+ * size).
*/
static void settlbcam(int index, unsigned long virt, phys_addr_t phys,
unsigned long size, unsigned long flags, unsigned int pid)
{
- unsigned int tsize, lz;
+ unsigned int tsize;
- asm (PPC_CNTLZL "%0,%1" : "=r" (lz) : "r" (size));
- tsize = 21 - lz;
+ tsize = __ilog2(size) - 10;
#ifdef CONFIG_SMP
if ((flags & _PAGE_NO_CACHE) == 0)
@@ -146,29 +146,36 @@ static void settlbcam(int index, unsigned long virt, phys_addr_t phys,
loadcam_entry(index);
}
+unsigned long calc_cam_sz(unsigned long ram, unsigned long virt,
+ phys_addr_t phys)
+{
+ unsigned int camsize = __ilog2(ram) & ~1U;
+ unsigned int align = __ffs(virt | phys) & ~1U;
+ unsigned long max_cam = (mfspr(SPRN_TLB1CFG) >> 16) & 0xf;
+
+ /* Convert (4^max) kB to (2^max) bytes */
+ max_cam = max_cam * 2 + 10;
+
+ if (camsize > align)
+ camsize = align;
+ if (camsize > max_cam)
+ camsize = max_cam;
+
+ return 1UL << camsize;
+}
+
unsigned long map_mem_in_cams(unsigned long ram, int max_cam_idx)
{
int i;
unsigned long virt = PAGE_OFFSET;
phys_addr_t phys = memstart_addr;
unsigned long amount_mapped = 0;
- unsigned long max_cam = (mfspr(SPRN_TLB1CFG) >> 16) & 0xf;
-
- /* Convert (4^max) kB to (2^max) bytes */
- max_cam = max_cam * 2 + 10;
/* Calculate CAM values */
for (i = 0; ram && i < max_cam_idx; i++) {
- unsigned int camsize = __ilog2(ram) & ~1U;
- unsigned int align = __ffs(virt | phys) & ~1U;
unsigned long cam_sz;
- if (camsize > align)
- camsize = align;
- if (camsize > max_cam)
- camsize = max_cam;
-
- cam_sz = 1UL << camsize;
+ cam_sz = calc_cam_sz(ram, virt, phys);
settlbcam(i, virt, phys, cam_sz, PAGE_KERNEL_X, 0);
ram -= cam_sz;