[ppc4xx] Extend program_tlb() with virtual & physical addresses

Now program_tlb() allows to program a TLB (or multiple) with
different virtual and physical addresses. With this change, now one
physical region (e.g. SDRAM) can be mapped 2 times, once with caches
diabled and once with caches enabled.

Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/cpu/ppc4xx/tlb.c b/cpu/ppc4xx/tlb.c
index 50344a4..6c916ef 100644
--- a/cpu/ppc4xx/tlb.c
+++ b/cpu/ppc4xx/tlb.c
@@ -36,7 +36,8 @@
 	unsigned long tlb_word2_i_value;
 } region_t;
 
-static int add_tlb_entry(unsigned long base_addr,
+static int add_tlb_entry(unsigned long phys_addr,
+			 unsigned long virt_addr,
 			 unsigned long tlb_word0_size_value,
 			 unsigned long tlb_word2_i_value)
 {
@@ -55,9 +56,9 @@
 		return -1;
 
 	/* Second, create the TLB entry */
-	tlb_word0_value = TLB_WORD0_EPN_ENCODE(base_addr) | TLB_WORD0_V_ENABLE |
+	tlb_word0_value = TLB_WORD0_EPN_ENCODE(virt_addr) | TLB_WORD0_V_ENABLE |
 		TLB_WORD0_TS_0 | tlb_word0_size_value;
-	tlb_word1_value = TLB_WORD1_RPN_ENCODE(base_addr) | TLB_WORD1_ERPN_ENCODE(0);
+	tlb_word1_value = TLB_WORD1_RPN_ENCODE(phys_addr) | TLB_WORD1_ERPN_ENCODE(0);
 	tlb_word2_value = TLB_WORD2_U0_DISABLE | TLB_WORD2_U1_DISABLE |
 		TLB_WORD2_U2_DISABLE | TLB_WORD2_U3_DISABLE |
 		TLB_WORD2_W_DISABLE | tlb_word2_i_value |
@@ -81,7 +82,9 @@
 	return 0;
 }
 
-static void program_tlb_addr(unsigned long base_addr, unsigned long mem_size,
+static void program_tlb_addr(unsigned long phys_addr,
+			     unsigned long virt_addr,
+			     unsigned long mem_size,
 			     unsigned long tlb_word2_i_value)
 {
 	int rc;
@@ -91,70 +94,78 @@
 	while (mem_size != 0) {
 		rc = 0;
 		/* Add the TLB entries in to map the region. */
-		if (((base_addr & TLB_256MB_ALIGN_MASK) == base_addr) &&
+		if (((phys_addr & TLB_256MB_ALIGN_MASK) == phys_addr) &&
 		    (mem_size >= TLB_256MB_SIZE)) {
 			/* Add a 256MB TLB entry */
-			if ((rc = add_tlb_entry(base_addr, TLB_WORD0_SIZE_256MB, tlb_i)) == 0) {
+			if ((rc = add_tlb_entry(phys_addr, virt_addr,
+						TLB_WORD0_SIZE_256MB, tlb_i)) == 0) {
 				mem_size -= TLB_256MB_SIZE;
-				base_addr += TLB_256MB_SIZE;
+				phys_addr += TLB_256MB_SIZE;
 			}
-		} else if (((base_addr & TLB_16MB_ALIGN_MASK) == base_addr) &&
+		} else if (((phys_addr & TLB_16MB_ALIGN_MASK) == phys_addr) &&
 			   (mem_size >= TLB_16MB_SIZE)) {
 			/* Add a 16MB TLB entry */
-			if ((rc = add_tlb_entry(base_addr, TLB_WORD0_SIZE_16MB, tlb_i)) == 0) {
+			if ((rc = add_tlb_entry(phys_addr, virt_addr,
+						TLB_WORD0_SIZE_16MB, tlb_i)) == 0) {
 				mem_size -= TLB_16MB_SIZE;
-				base_addr += TLB_16MB_SIZE;
+				phys_addr += TLB_16MB_SIZE;
 			}
-		} else if (((base_addr & TLB_1MB_ALIGN_MASK) == base_addr) &&
+		} else if (((phys_addr & TLB_1MB_ALIGN_MASK) == phys_addr) &&
 			   (mem_size >= TLB_1MB_SIZE)) {
 			/* Add a 1MB TLB entry */
-			if ((rc = add_tlb_entry(base_addr, TLB_WORD0_SIZE_1MB, tlb_i)) == 0) {
+			if ((rc = add_tlb_entry(phys_addr, virt_addr,
+						TLB_WORD0_SIZE_1MB, tlb_i)) == 0) {
 				mem_size -= TLB_1MB_SIZE;
-				base_addr += TLB_1MB_SIZE;
+				phys_addr += TLB_1MB_SIZE;
 			}
-		} else if (((base_addr & TLB_256KB_ALIGN_MASK) == base_addr) &&
+		} else if (((phys_addr & TLB_256KB_ALIGN_MASK) == phys_addr) &&
 			   (mem_size >= TLB_256KB_SIZE)) {
 			/* Add a 256KB TLB entry */
-			if ((rc = add_tlb_entry(base_addr, TLB_WORD0_SIZE_256KB, tlb_i)) == 0) {
+			if ((rc = add_tlb_entry(phys_addr, virt_addr,
+						TLB_WORD0_SIZE_256KB, tlb_i)) == 0) {
 				mem_size -= TLB_256KB_SIZE;
-				base_addr += TLB_256KB_SIZE;
+				phys_addr += TLB_256KB_SIZE;
 			}
-		} else if (((base_addr & TLB_64KB_ALIGN_MASK) == base_addr) &&
+		} else if (((phys_addr & TLB_64KB_ALIGN_MASK) == phys_addr) &&
 			   (mem_size >= TLB_64KB_SIZE)) {
 			/* Add a 64KB TLB entry */
-			if ((rc = add_tlb_entry(base_addr, TLB_WORD0_SIZE_64KB, tlb_i)) == 0) {
+			if ((rc = add_tlb_entry(phys_addr, virt_addr,
+						TLB_WORD0_SIZE_64KB, tlb_i)) == 0) {
 				mem_size -= TLB_64KB_SIZE;
-				base_addr += TLB_64KB_SIZE;
+				phys_addr += TLB_64KB_SIZE;
 			}
-		} else if (((base_addr & TLB_16KB_ALIGN_MASK) == base_addr) &&
+		} else if (((phys_addr & TLB_16KB_ALIGN_MASK) == phys_addr) &&
 			   (mem_size >= TLB_16KB_SIZE)) {
 			/* Add a 16KB TLB entry */
-			if ((rc = add_tlb_entry(base_addr, TLB_WORD0_SIZE_16KB, tlb_i)) == 0) {
+			if ((rc = add_tlb_entry(phys_addr, virt_addr,
+						TLB_WORD0_SIZE_16KB, tlb_i)) == 0) {
 				mem_size -= TLB_16KB_SIZE;
-				base_addr += TLB_16KB_SIZE;
+				phys_addr += TLB_16KB_SIZE;
 			}
-		} else if (((base_addr & TLB_4KB_ALIGN_MASK) == base_addr) &&
+		} else if (((phys_addr & TLB_4KB_ALIGN_MASK) == phys_addr) &&
 			   (mem_size >= TLB_4KB_SIZE)) {
 			/* Add a 4KB TLB entry */
-			if ((rc = add_tlb_entry(base_addr, TLB_WORD0_SIZE_4KB, tlb_i)) == 0) {
+			if ((rc = add_tlb_entry(phys_addr, virt_addr,
+						TLB_WORD0_SIZE_4KB, tlb_i)) == 0) {
 				mem_size -= TLB_4KB_SIZE;
-				base_addr += TLB_4KB_SIZE;
+				phys_addr += TLB_4KB_SIZE;
 			}
-		} else if (((base_addr & TLB_1KB_ALIGN_MASK) == base_addr) &&
+		} else if (((phys_addr & TLB_1KB_ALIGN_MASK) == phys_addr) &&
 			   (mem_size >= TLB_1KB_SIZE)) {
 			/* Add a 1KB TLB entry */
-			if ((rc = add_tlb_entry(base_addr, TLB_WORD0_SIZE_1KB, tlb_i)) == 0) {
+			if ((rc = add_tlb_entry(phys_addr, virt_addr,
+						TLB_WORD0_SIZE_1KB, tlb_i)) == 0) {
 				mem_size -= TLB_1KB_SIZE;
-				base_addr += TLB_1KB_SIZE;
+				phys_addr += TLB_1KB_SIZE;
 			}
 		} else {
 			printf("ERROR: no TLB size exists for the base address 0x%0X.\n",
-				base_addr);
+				phys_addr);
 		}
 
 		if (rc != 0)
 			printf("ERROR: no TLB entries available for the base addr 0x%0X.\n",
-				base_addr);
+				phys_addr);
 	}
 
 	return;
@@ -166,16 +177,16 @@
  * Common usage for boards with SDRAM DIMM modules to dynamically
  * configure the TLB's for the SDRAM
  */
-void program_tlb(u32 start, u32 size, u32 tlb_word2_i_value)
+void program_tlb(u32 phys_addr, u32 virt_addr, u32 size, u32 tlb_word2_i_value)
 {
 	region_t region_array;
 
-	region_array.base = start;
+	region_array.base = phys_addr;
 	region_array.size = size;
 	region_array.tlb_word2_i_value = tlb_word2_i_value;	/* en-/disable cache */
 
 	/* Call the routine to add in the tlb entries for the memory regions */
-	program_tlb_addr(region_array.base, region_array.size,
+	program_tlb_addr(region_array.base, virt_addr, region_array.size,
 			 region_array.tlb_word2_i_value);
 
 	return;