parisc: BTLB: Initialize BTLB tables at CPU startup

[linux-2.6-microblaze.git] / arch / parisc / mm / init.c

diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c
index a088c24..a2a3e89 100644 (file)
--- a/arch/parisc/mm/init.c
+++ b/arch/parisc/mm/init.c
@@ -32,6 +32,7 @@
 #include <asm/sections.h>
 #include <asm/msgbuf.h>
 #include <asm/sparsemem.h>
+#include <asm/asm-offsets.h>
 
 extern int  data_start;
 extern void parisc_kernel_start(void); /* Kernel entry point in head.S */
@@ -720,6 +721,77 @@ void __init paging_init(void)
        parisc_bootmem_free();
 }
 
+static void alloc_btlb(unsigned long start, unsigned long end, int *slot,
+                       unsigned long entry_info)
+{
+       const int slot_max = btlb_info.fixed_range_info.num_comb;
+       int min_num_pages = btlb_info.min_size;
+       unsigned long size;
+
+       /* map at minimum 4 pages */
+       if (min_num_pages < 4)
+               min_num_pages = 4;
+
+       size = HUGEPAGE_SIZE;
+       while (start < end && *slot < slot_max && size >= PAGE_SIZE) {
+               /* starting address must have same alignment as size! */
+               /* if correctly aligned and fits in double size, increase */
+               if (((start & (2 * size - 1)) == 0) &&
+                   (end - start) >= (2 * size)) {
+                       size <<= 1;
+                       continue;
+               }
+               /* if current size alignment is too big, try smaller size */
+               if ((start & (size - 1)) != 0) {
+                       size >>= 1;
+                       continue;
+               }
+               if ((end - start) >= size) {
+                       if ((size >> PAGE_SHIFT) >= min_num_pages)
+                               pdc_btlb_insert(start >> PAGE_SHIFT, __pa(start) >> PAGE_SHIFT,
+                                       size >> PAGE_SHIFT, entry_info, *slot);
+                       (*slot)++;
+                       start += size;
+                       continue;
+               }
+               size /= 2;
+               continue;
+       }
+}
+
+void btlb_init_per_cpu(void)
+{
+       unsigned long s, t, e;
+       int slot;
+
+       /* BTLBs are not available on 64-bit CPUs */
+       if (IS_ENABLED(CONFIG_PA20))
+               return;
+       else if (pdc_btlb_info(&btlb_info) < 0) {
+               memset(&btlb_info, 0, sizeof btlb_info);
+       }
+
+       /* insert BLTLBs for code and data segments */
+       s = (uintptr_t) dereference_function_descriptor(&_stext);
+       e = (uintptr_t) dereference_function_descriptor(&_etext);
+       t = (uintptr_t) dereference_function_descriptor(&_sdata);
+       BUG_ON(t != e);
+
+       /* code segments */
+       slot = 0;
+       alloc_btlb(s, e, &slot, 0x13800000);
+
+       /* sanity check */
+       t = (uintptr_t) dereference_function_descriptor(&_edata);
+       e = (uintptr_t) dereference_function_descriptor(&__bss_start);
+       BUG_ON(t != e);
+
+       /* data segments */
+       s = (uintptr_t) dereference_function_descriptor(&_sdata);
+       e = (uintptr_t) dereference_function_descriptor(&__bss_stop);
+       alloc_btlb(s, e, &slot, 0x11800000);
+}
+
 #ifdef CONFIG_PA20
 
 /*