From: Kees Jongenburger <kees.jongenburger@gmail.com>
Date: Thu, 16 May 2013 08:11:12 +0000 (+0200)
Subject: arm:vm caching fix.
X-Git-Tag: v3.3.0~980
X-Git-Url: http://zhaoyanbai.com/repos/%22http:/www.isc.org/icons/zlib_tech.html?a=commitdiff_plain;h=1e1ff96aea1630c3b6ced276a2da114bed793086;p=minix.git

arm:vm caching fix.

Improve reliability by using write trough cache.
---

diff --git a/kernel/arch/earm/memory.c b/kernel/arch/earm/memory.c
index 7d2123ada..00de13ea7 100644
--- a/kernel/arch/earm/memory.c
+++ b/kernel/arch/earm/memory.c
@@ -103,7 +103,7 @@ static phys_bytes createpde(
 		pdeval = (linaddr & ARM_VM_SECTION_MASK)
 			| ARM_VM_SECTION
 			| ARM_VM_SECTION_DOMAIN
-			| ARM_VM_SECTION_WT
+			| ARM_VM_SECTION_DEVICE
 			| ARM_VM_SECTION_USER;
 	}
 
@@ -684,6 +684,7 @@ static int device_mem_mapping_index = -1,
 
 char *device_mem;
 
+/* defined in kernel.lds */
 extern char usermapped_start, usermapped_end, usermapped_nonglo_start;
 
 int arch_phys_map(const int index,
diff --git a/kernel/arch/earm/pg_utils.c b/kernel/arch/earm/pg_utils.c
index 2895aa314..b2d696d1e 100644
--- a/kernel/arch/earm/pg_utils.c
+++ b/kernel/arch/earm/pg_utils.c
@@ -200,7 +200,6 @@ void vm_enable_paging(void)
 	/* Enable MMU */
 	sctlr |= SCTLR_M;
 
-	/* AFE set to zero (default reset value): not using simplified model. */
 	/* TRE set to zero (default reset value): TEX[2:0] are used, plus C and B bits.*/
 	sctlr &= ~SCTLR_TRE;
 
diff --git a/servers/vm/arch/i386/pagetable.c b/servers/vm/arch/i386/pagetable.c
index 0cb8a62ae..8008f1138 100644
--- a/servers/vm/arch/i386/pagetable.c
+++ b/servers/vm/arch/i386/pagetable.c
@@ -301,7 +301,7 @@ void *vm_mappages(phys_bytes p, int pages)
 	if((r=pt_writemap(vmprocess, pt, loc, p, VM_PAGE_SIZE*pages,
 		ARCH_VM_PTE_PRESENT | ARCH_VM_PTE_USER | ARCH_VM_PTE_RW
 #if defined(__arm__)
-		| ARM_VM_PTE_WB
+		| ARM_VM_PTE_WT
 #endif
 		, 0)) != OK) {
 		printf("vm_mappages writemap failed\n");
@@ -409,7 +409,7 @@ void vm_pagelock(void *vir, int lockflag)
 #if defined(__arm__)
 	else
 		flags |= ARCH_VM_PTE_RO;
-	flags |= ARM_VM_PTE_WB | ARM_VM_PTE_S ; // LSC FIXME
+	flags |= ARM_VM_PTE_WT ;
 #endif
 
 	/* Update flags. */
@@ -689,7 +689,7 @@ int pt_ptmap(struct vmproc *src_vmp, struct vmproc *dst_vmp)
 #elif defined(__arm__)
 	if((r=pt_writemap(dst_vmp, &dst_vmp->vm_pt, viraddr, physaddr, ARCH_PAGEDIR_SIZE,
 		ARCH_VM_PTE_PRESENT | ARCH_VM_PTE_USER |
-		ARM_VM_PTE_WB | ARM_VM_PTE_S, //LSC FIXME
+		ARM_VM_PTE_WT ,
 #endif
 		WMF_OVERWRITE)) != OK) {
 		return r;
@@ -715,7 +715,7 @@ int pt_ptmap(struct vmproc *src_vmp, struct vmproc *dst_vmp)
 		if((r=pt_writemap(dst_vmp, &dst_vmp->vm_pt, viraddr, physaddr, VM_PAGE_SIZE,
 			ARCH_VM_PTE_PRESENT | ARCH_VM_PTE_USER | ARCH_VM_PTE_RW
 #ifdef __arm__
-			| ARM_VM_PTE_WB
+			| ARM_VM_PTE_WT
 #endif
 			,
 			WMF_OVERWRITE)) != OK) {
@@ -874,6 +874,7 @@ int pt_writemap(struct vmproc * vmp,
 				/* If we expect a writable page, allow a readonly page. */
 				maskedentry &= ~ARCH_VM_PTE_RO;
 			}
+			maskedentry &= ~(ARM_VM_PTE_WB|ARM_VM_PTE_WT);
 #endif
 			if(maskedentry != entry) {
 				printf("pt_writemap: mismatch: ");
@@ -1377,7 +1378,7 @@ int pt_mapkernel(pt_t *pt)
 		pt->pt_dir[kern_pde] = (addr & ARCH_VM_PDE_MASK)
 			| ARM_VM_SECTION
 			| ARM_VM_SECTION_DOMAIN
-			| ARM_VM_SECTION_WB
+			| ARM_VM_SECTION_WT
 			| ARM_VM_SECTION_SUPER;
 #endif
 		kern_pde++;
@@ -1412,8 +1413,7 @@ int pt_mapkernel(pt_t *pt)
 				assert(!pt->pt_dir[map_pde]);
 				pt->pt_dir[map_pde] = addr |
 					ARM_VM_SECTION | ARM_VM_SECTION_DOMAIN |
-					ARM_VM_SECTION_WB |
-					ARM_VM_SECTION_SHAREABLE |
+					ARM_VM_SECTION_DEVICE |
 					ARM_VM_SECTION_SUPER;
 				addr += ARCH_BIG_PAGE_SIZE;
 			}
diff --git a/servers/vm/region.c b/servers/vm/region.c
index a77f415dd..53611931d 100644
--- a/servers/vm/region.c
+++ b/servers/vm/region.c
@@ -270,7 +270,8 @@ int map_ph_writept(struct vmproc *vmp, struct vir_region *vr,
 #if  defined(__arm__)
 	if (pb->phys >= 0x80000000 && pb->phys < (0xc0000000 - VM_PAGE_SIZE)) {
 		// LSC Do this only for actual RAM
-		flags |= ARM_VM_PTE_WT;
+		// KEJO:fishy will need to look into this 
+		flags |= ARM_VM_PTE_DEVICE;
 	}
 #endif