Dynamically allocate page tables; setup as per MILO.
diff --git a/init.c b/init.c
index c3ac97a..d8b9b4c 100644
--- a/init.c
+++ b/init.c
@@ -8,14 +8,17 @@
#define PAGE_SIZE (1ul << PAGE_SHIFT)
#define PAGE_OFFSET 0xfffffc0000000000UL
+#if 1
+#define PA(VA) ((unsigned long)(unsigned int)(VA))
+#else
+#define PA(VA) ((VA) - PAGE_OFFSET)
+#endif
+#define VA(PA) ((PA) + PAGE_OFFSET)
+
#define HZ 1024
struct pcb_struct pal_pcb __attribute__((section(".sbss")));
-unsigned long page_dir[1024] __attribute__((aligned(PAGE_SIZE)));
-unsigned long page_L1[1024] __attribute__((aligned(PAGE_SIZE)));
-unsigned long page_L2[1024][1024] __attribute__((aligned(PAGE_SIZE)));
-
struct hwrpb_combine {
struct hwrpb_struct hwrpb;
struct percpu_struct processor;
@@ -27,7 +30,7 @@
.hwrpb.size = sizeof(struct hwrpb_struct),
.hwrpb.pagesize = PAGE_SIZE,
- .hwrpb.ssn = "QEMU",
+ .hwrpb.ssn = "MILO QEMU",
/* ??? This should match TARGET_PHYS_ADDR_SPACE_BITS from qemu. */
.hwrpb.pa_bits = 44,
@@ -58,6 +61,20 @@
.mc[0].usage = 2
};
+unsigned long page_dir[1024] __attribute__((aligned(PAGE_SIZE)));
+
+extern char _end[];
+static unsigned long last_alloc = (unsigned long)_end;
+
+static void *
+alloc (unsigned long size, unsigned long align)
+{
+ unsigned long p = (last_alloc + align - 1) & ~(align - 1);
+
+ last_alloc = p + size;
+ return (void *)p;
+}
+
static unsigned long
init_cpuid (void)
{
@@ -99,16 +116,11 @@
static void
init_hwrpb (unsigned long memsize)
{
- unsigned long end, pal_pages;
+ unsigned long pal_pages;
- hwrpb.hwrpb.phys_addr = (unsigned int)(unsigned long)&hwrpb;
+ hwrpb.hwrpb.phys_addr = PA((unsigned long)&hwrpb);
- /* ??? For some reason GCC wants to use a LITERAL relocation for
- _end instead of gp-relative relocations. */
- __asm ("ldah %0,_end($gp) !gprelhigh\n\tlda %0,_end(%0) !gprellow"
- : "=r"(end));
-
- pal_pages = ((unsigned int)end + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ pal_pages = (PA(last_alloc) + PAGE_SIZE - 1) >> PAGE_SHIFT;
hwrpb.mc[0].numpages = pal_pages;
hwrpb.mc[1].start_pfn = pal_pages;
@@ -120,7 +132,7 @@
static void
init_pcb (void)
{
- pal_pcb.ptbr = (unsigned int)(unsigned long)page_dir;
+ pal_pcb.ptbr = PA((unsigned long)page_dir);
pal_pcb.flags = 1;
}
@@ -129,8 +141,8 @@
{
unsigned long bits;
- bits = ((unsigned long)page - PAGE_OFFSET) << (32 - PAGE_SHIFT);
- bits |= _PAGE_VALID;
+ bits = PA((unsigned long)page) << (32 - PAGE_SHIFT);
+ bits += _PAGE_VALID | _PAGE_KRE | _PAGE_KWE;
return bits;
}
@@ -138,7 +150,7 @@
static inline void *
pte_page (unsigned long pte)
{
- return (void *)((pte >> 32 << PAGE_SHIFT) + PAGE_OFFSET);
+ return (void *)VA(pte >> 32 << PAGE_SHIFT);
}
static void
@@ -151,57 +163,50 @@
if (pt[index] != 0)
pt = pte_page (pt[index]);
else
- __builtin_trap();
+ {
+ unsigned long *npt = alloc(PAGE_SIZE, PAGE_SIZE);
+ pt[index] = build_pte (npt);
+ pt = npt;
+ }
index = (addr >> (PAGE_SHIFT+10)) % 1024;
if (pt[index] != 0)
pt = pte_page (pt[index]);
else
- __builtin_trap();
+ {
+ unsigned long *npt = alloc(PAGE_SIZE, PAGE_SIZE);
+ pt[index] = build_pte (npt);
+ pt = npt;
+ }
index = (addr >> PAGE_SHIFT) % 1024;
pt[index] = build_pte (page);
}
static void
-init_page_table (unsigned long memsize, unsigned long pal_pages)
+init_page_table (unsigned long memsize)
{
unsigned long i, addr, max_addr, page;
- page_dir[0] = build_pte (page_L1);
-
- for (i = 0; i < 1024; ++i)
- page_L1[i] = build_pte (page_L2[i]);
-
set_pte ((unsigned long)INIT_HWRPB, &hwrpb);
- addr = 0x20000000ul;
- max_addr = 1ul << (PAGE_SHIFT + 20);
- page = pal_pages << PAGE_SHIFT;
-
- while (addr < max_addr && page < memsize)
- {
- set_pte (addr, (void *)(PAGE_OFFSET + page));
- addr += PAGE_SIZE;
- page += PAGE_SIZE;
- }
-
/* SRM places the self-map for the VPTBR in the second entry. */
- page_dir[1] = build_pte (page_dir);
+ /* MILO places the self-map for the VPTBR in the last entry. */
+ page_dir[1023] = build_pte (page_dir);
/* Write the SRM vptptr. */
{
- register unsigned long a0 __asm__("$16") = max_addr;
+ register unsigned long a0 __asm__("$16") = 0xfffffffe00000000UL;
__asm ("call_pal 0x2d" : : "r"(a0));
}
}
void
-do_start(unsigned long memsize)
+do_start(unsigned long memsize, void (*kernel_entry)(void))
{
+ init_page_table (memsize);
init_hwrpb (memsize);
init_pcb ();
- init_page_table (memsize, hwrpb.mc[0].numpages);
uart_init ();
uart_puts (COM1, "Hello, World!\n");
diff --git a/pal.S b/pal.S
index f99d088..a570293 100644
--- a/pal.S
+++ b/pal.S
@@ -189,6 +189,7 @@
// Load the initial PCB and page table elements.
lda t0, page_dir($gp) !gprel
+ zap t0, 0xf0, t0
mtpr t0, qemu_ptbr
lda t0, pal_pcb($gp) !gprel
