sh: Build PMB entry links for existing contiguous multi-page mappings.

This plugs in entry sizing support for existing mappings and then builds
on top of that for linking together entries that are mapping contiguous
areas. This will ultimately permit us to coalesce mappings and promote
head pages while reclaiming PMB slots for dynamic remapping.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

diff --git a/arch/sh/include/asm/mmu.h b/arch/sh/include/asm/mmu.h
index 44c904341414d0791a76f9c166d972566204c13f..5453169bf0529a259bd3197557f478307e0946fa 100644 (file)
--- a/arch/sh/include/asm/mmu.h
+++ b/arch/sh/include/asm/mmu.h
@@ -59,6 +59,7 @@ struct pmb_entry {
        unsigned long vpn;
        unsigned long ppn;
        unsigned long flags;
+       unsigned long size;
 
        /*
         * 0 .. NR_PMB_ENTRIES for specific entry selection, or
@@ -66,7 +67,6 @@ struct pmb_entry {
         */
        int entry;
 
-       struct pmb_entry *next;
        /* Adjacent entry link for contiguous multi-entry mappings */
        struct pmb_entry *link;
 };

diff --git a/arch/sh/mm/pmb.c b/arch/sh/mm/pmb.c
index 924f3e4b3a82f145859bf4379f1b1c5d297179ed..f2ad6e374b648eaec2d3a9f329078add82396a12 100644 (file)
--- a/arch/sh/mm/pmb.c
+++ b/arch/sh/mm/pmb.c
@@ -90,20 +90,15 @@ static struct pmb_entry *pmb_alloc(unsigned long vpn, unsigned long ppn,
        pmbe->ppn       = ppn;
        pmbe->flags     = flags;
        pmbe->entry     = pos;
+       pmbe->size      = 0;
 
        return pmbe;
 }
 
 static void pmb_free(struct pmb_entry *pmbe)
 {
-       int pos = pmbe->entry;
-
-       pmbe->vpn       = 0;
-       pmbe->ppn       = 0;
-       pmbe->flags     = 0;
-       pmbe->entry     = 0;
-
-       clear_bit(pos, pmb_map);
+       clear_bit(pmbe->entry, pmb_map);
+       pmbe->entry = PMB_NO_ENTRY;
 }
 
 /*
@@ -198,6 +193,8 @@ again:
                vaddr   += pmb_sizes[i].size;
                size    -= pmb_sizes[i].size;
 
+               pmbe->size = pmb_sizes[i].size;
+
                /*
                 * Link adjacent entries that span multiple PMB entries
                 * for easier tear-down.
@@ -273,25 +270,7 @@ static void pmb_unmap_entry(struct pmb_entry *pmbe)
        } while (pmbe);
 }
 
-static inline void
-pmb_log_mapping(unsigned long data_val, unsigned long vpn, unsigned long ppn)
-{
-       unsigned int size;
-       const char *sz_str;
-
-       size = data_val & PMB_SZ_MASK;
-
-       sz_str = (size == PMB_SZ_16M)  ? " 16MB":
-                (size == PMB_SZ_64M)  ? " 64MB":
-                (size == PMB_SZ_128M) ? "128MB":
-                                        "512MB";
-
-       pr_info("\t0x%08lx -> 0x%08lx [ %s %scached ]\n",
-               vpn >> PAGE_SHIFT, ppn >> PAGE_SHIFT, sz_str,
-               (data_val & PMB_C) ? "" : "un");
-}
-
-static inline unsigned int pmb_ppn_in_range(unsigned long ppn)
+static __always_inline unsigned int pmb_ppn_in_range(unsigned long ppn)
 {
        return ppn >= __pa(memory_start) && ppn < __pa(memory_end);
 }
@@ -299,7 +278,8 @@ static inline unsigned int pmb_ppn_in_range(unsigned long ppn)
 static int pmb_synchronize_mappings(void)
 {
        unsigned int applied = 0;
-       int i;
+       struct pmb_entry *pmbp = NULL;
+       int i, j;
 
        pr_info("PMB: boot mappings:\n");
 
@@ -323,6 +303,7 @@ static int pmb_synchronize_mappings(void)
                unsigned long addr, data;
                unsigned long addr_val, data_val;
                unsigned long ppn, vpn, flags;
+               unsigned int size;
                struct pmb_entry *pmbe;
 
                addr = mk_pmb_addr(i);
@@ -366,7 +347,8 @@ static int pmb_synchronize_mappings(void)
                        __raw_writel(data_val, data);
                }
 
-               flags = data_val & (PMB_SZ_MASK | PMB_CACHE_MASK);
+               size = data_val & PMB_SZ_MASK;
+               flags = size | (data_val & PMB_CACHE_MASK);
 
                pmbe = pmb_alloc(vpn, ppn, flags, i);
                if (IS_ERR(pmbe)) {
@@ -374,7 +356,24 @@ static int pmb_synchronize_mappings(void)
                        continue;
                }
 
-               pmb_log_mapping(data_val, vpn, ppn);
+               for (j = 0; j < ARRAY_SIZE(pmb_sizes); j++)
+                       if (pmb_sizes[j].flag == size)
+                               pmbe->size = pmb_sizes[j].size;
+
+               /*
+                * Compare the previous entry against the current one to
+                * see if the entries span a contiguous mapping. If so,
+                * setup the entry links accordingly.
+                */
+               if (pmbp && ((pmbe->vpn == (pmbp->vpn + pmbp->size)) &&
+                            (pmbe->ppn == (pmbp->ppn + pmbp->size))))
+                       pmbp->link = pmbe;
+
+               pmbp = pmbe;
+
+               pr_info("\t0x%08lx -> 0x%08lx [ %ldMB %scached ]\n",
+                       vpn >> PAGE_SHIFT, ppn >> PAGE_SHIFT, pmbe->size >> 20,
+                       (data_val & PMB_C) ? "" : "un");
 
                applied++;
        }