1 files changed, 75 insertions, 7 deletions

diff --git a/sys/i386/i386/pmap.c b/sys/i386/i386/pmap.c
index 4e09a90..540eb65 100644
--- a/sys/i386/i386/pmap.c
+++ b/sys/i386/i386/pmap.c
@@ -232,6 +232,18 @@ SYSCTL_INT(_vm_pmap, OID_AUTO, pg_ps_enabled, CTLFLAG_RDTUN, &pg_ps_enabled, 0,
 #define	PAT_INDEX_SIZE	8
 static int pat_index[PAT_INDEX_SIZE];	/* cache mode to PAT index conversion */
 
+/*
+ * pmap_mapdev support pre initialization (i.e. console)
+ */
+#define	PMAP_PREINIT_MAPPING_COUNT	8
+static struct pmap_preinit_mapping {
+	vm_paddr_t	pa;
+	vm_offset_t	va;
+	vm_size_t	sz;
+	int		mode;
+} pmap_preinit_mapping[PMAP_PREINIT_MAPPING_COUNT];
+static int pmap_initialized;
+
 static struct rwlock_padalign pvh_global_lock;
 
 /*
@@ -731,6 +743,7 @@ pmap_ptelist_init(vm_offset_t *head, void *base, int npages)
 void
 pmap_init(void)
 {
+	struct pmap_preinit_mapping *ppim;
 	vm_page_t mpte;
 	vm_size_t s;
 	int i, pv_npg;
@@ -814,6 +827,17 @@ pmap_init(void)
 	    UMA_ZONE_VM | UMA_ZONE_NOFREE);
 	uma_zone_set_allocf(pdptzone, pmap_pdpt_allocf);
 #endif
+
+	pmap_initialized = 1;
+	if (!bootverbose)
+		return;
+	for (i = 0; i < PMAP_PREINIT_MAPPING_COUNT; i++) {
+		ppim = pmap_preinit_mapping + i;
+		if (ppim->va == 0)
+			continue;
+		printf("PPIM %u: PA=%#jx, VA=%#x, size=%#x, mode=%#x\n", i,
+		    (uintmax_t)ppim->pa, ppim->va, ppim->sz, ppim->mode);
+	}
 }
 
 
@@ -5162,8 +5186,10 @@ pmap_pde_attr(pd_entry_t *pde, int cache_bits)
 void *
 pmap_mapdev_attr(vm_paddr_t pa, vm_size_t size, int mode)
 {
+	struct pmap_preinit_mapping *ppim;
 	vm_offset_t va, offset;
 	vm_size_t tmpsize;
+	int i;
 
 	offset = pa & PAGE_MASK;
 	size = round_page(offset + size);
@@ -5171,11 +5197,36 @@ pmap_mapdev_attr(vm_paddr_t pa, vm_size_t size, int mode)
 
 	if (pa < KERNLOAD && pa + size <= KERNLOAD)
 		va = KERNBASE + pa;
-	else
+	else if (!pmap_initialized) {
+		va = 0;
+		for (i = 0; i < PMAP_PREINIT_MAPPING_COUNT; i++) {
+			ppim = pmap_preinit_mapping + i;
+			if (ppim->va == 0) {
+				ppim->pa = pa;
+				ppim->sz = size;
+				ppim->mode = mode;
+				ppim->va = virtual_avail;
+				virtual_avail += size;
+				va = ppim->va;
+				break;
+			}
+		}
+		if (va == 0)
+			panic("%s: too many preinit mappings", __func__);
+	} else {
+		/*
+		 * If we have a preinit mapping, re-use it.
+		 */
+		for (i = 0; i < PMAP_PREINIT_MAPPING_COUNT; i++) {
+			ppim = pmap_preinit_mapping + i;
+			if (ppim->pa == pa && ppim->sz == size &&
+			    ppim->mode == mode)
+				return ((void *)(ppim->va + offset));
+		}
 		va = kva_alloc(size);
-	if (!va)
-		panic("pmap_mapdev: Couldn't alloc kernel virtual memory");
-
+		if (va == 0)
+			panic("%s: Couldn't allocate KVA", __func__);
+	}
 	for (tmpsize = 0; tmpsize < size; tmpsize += PAGE_SIZE)
 		pmap_kenter_attr(va + tmpsize, pa + tmpsize, mode);
 	pmap_invalidate_range(kernel_pmap, va, va + tmpsize);
@@ -5200,14 +5251,31 @@ pmap_mapbios(vm_paddr_t pa, vm_size_t size)
 void
 pmap_unmapdev(vm_offset_t va, vm_size_t size)
 {
-	vm_offset_t base, offset;
+	struct pmap_preinit_mapping *ppim;
+	vm_offset_t offset;
+	int i;
 
 	if (va >= KERNBASE && va + size <= KERNBASE + KERNLOAD)
 		return;
-	base = trunc_page(va);
 	offset = va & PAGE_MASK;
 	size = round_page(offset + size);
-	kva_free(base, size);
+	va = trunc_page(va);
+	for (i = 0; i < PMAP_PREINIT_MAPPING_COUNT; i++) {
+		ppim = pmap_preinit_mapping + i;
+		if (ppim->va == va && ppim->sz == size) {
+			if (pmap_initialized)
+				return;
+			ppim->pa = 0;
+			ppim->va = 0;
+			ppim->sz = 0;
+			ppim->mode = 0;
+			if (va + size == virtual_avail)
+				virtual_avail = va;
+			return;
+		}
+	}
+	if (pmap_initialized)
+		kva_free(va, size);
 }
 
 /*