1 files changed, 141 insertions, 51 deletions

diff --git a/arch/arm/kernel/tcm.c b/arch/arm/kernel/tcm.c
index e50303868f1..7a3be1d4d0b 100644
--- a/arch/arm/kernel/tcm.c
+++ b/arch/arm/kernel/tcm.c
@@ -13,38 +13,37 @@
 #include <linux/ioport.h>
 #include <linux/genalloc.h>
 #include <linux/string.h> /* memcpy */
-#include <asm/page.h> /* PAGE_SHIFT */
 #include <asm/cputype.h>
 #include <asm/mach/map.h>
-#include <mach/memory.h>
-#include "tcm.h"
-
-/* Scream and warn about misuse */
-#if !defined(ITCM_OFFSET) || !defined(ITCM_END) || \
-    !defined(DTCM_OFFSET) || !defined(DTCM_END)
-#error "TCM support selected but offsets not defined!"
-#endif
+#include <asm/memory.h>
+#include <asm/system_info.h>
 
 static struct gen_pool *tcm_pool;
+static bool dtcm_present;
+static bool itcm_present;
 
 /* TCM section definitions from the linker */
 extern char __itcm_start, __sitcm_text, __eitcm_text;
 extern char __dtcm_start, __sdtcm_data, __edtcm_data;
 
+/* These will be increased as we run */
+u32 dtcm_end = DTCM_OFFSET;
+u32 itcm_end = ITCM_OFFSET;
+
 /*
  * TCM memory resources
  */
 static struct resource dtcm_res = {
 	.name = "DTCM RAM",
 	.start = DTCM_OFFSET,
-	.end = DTCM_END,
+	.end = DTCM_OFFSET,
 	.flags = IORESOURCE_MEM
 };
 
 static struct resource itcm_res = {
 	.name = "ITCM RAM",
 	.start = ITCM_OFFSET,
-	.end = ITCM_END,
+	.end = ITCM_OFFSET,
 	.flags = IORESOURCE_MEM
 };
 
@@ -52,8 +51,8 @@ static struct map_desc dtcm_iomap[] __initdata = {
 	{
 		.virtual	= DTCM_OFFSET,
 		.pfn		= __phys_to_pfn(DTCM_OFFSET),
-		.length		= (DTCM_END - DTCM_OFFSET + 1),
-		.type		= MT_UNCACHED
+		.length		= 0,
+		.type		= MT_MEMORY_RW_DTCM
 	}
 };
 
@@ -61,8 +60,8 @@ static struct map_desc itcm_iomap[] __initdata = {
 	{
 		.virtual	= ITCM_OFFSET,
 		.pfn		= __phys_to_pfn(ITCM_OFFSET),
-		.length		= (ITCM_END - ITCM_OFFSET + 1),
-		.type		= MT_UNCACHED
+		.length		= 0,
+		.type		= MT_MEMORY_RWX_ITCM,
 	}
 };
 
@@ -93,14 +92,36 @@ void tcm_free(void *addr, size_t len)
 }
 EXPORT_SYMBOL(tcm_free);
 
+bool tcm_dtcm_present(void)
+{
+	return dtcm_present;
+}
+EXPORT_SYMBOL(tcm_dtcm_present);
+
+bool tcm_itcm_present(void)
+{
+	return itcm_present;
+}
+EXPORT_SYMBOL(tcm_itcm_present);
 
-static void __init setup_tcm_bank(u8 type, u32 offset, u32 expected_size)
+static int __init setup_tcm_bank(u8 type, u8 bank, u8 banks,
+				  u32 *offset)
 {
 	const int tcm_sizes[16] = { 0, -1, -1, 4, 8, 16, 32, 64, 128,
 				    256, 512, 1024, -1, -1, -1, -1 };
 	u32 tcm_region;
 	int tcm_size;
 
+	/*
+	 * If there are more than one TCM bank of this type,
+	 * select the TCM bank to operate on in the TCM selection
+	 * register.
+	 */
+	if (banks > 1)
+		asm("mcr	p15, 0, %0, c9, c2, 0"
+		    : /* No output operands */
+		    : "r" (bank));
+
 	/* Read the special TCM region register c9, 0 */
 	if (!type)
 		asm("mrc	p15, 0, %0, c9, c1, 0"
@@ -111,26 +132,28 @@ static void __init setup_tcm_bank(u8 type, u32 offset, u32 expected_size)
 
 	tcm_size = tcm_sizes[(tcm_region >> 2) & 0x0f];
 	if (tcm_size < 0) {
-		pr_err("CPU: %sTCM of unknown size!\n",
-			type ? "I" : "D");
+		pr_err("CPU: %sTCM%d of unknown size\n",
+		       type ? "I" : "D", bank);
+		return -EINVAL;
+	} else if (tcm_size > 32) {
+		pr_err("CPU: %sTCM%d larger than 32k found\n",
+		       type ? "I" : "D", bank);
+		return -EINVAL;
 	} else {
-		pr_info("CPU: found %sTCM %dk @ %08x, %senabled\n",
+		pr_info("CPU: found %sTCM%d %dk @ %08x, %senabled\n",
 			type ? "I" : "D",
+			bank,
 			tcm_size,
 			(tcm_region & 0xfffff000U),
 			(tcm_region & 1) ? "" : "not ");
 	}
 
-	if (tcm_size != expected_size) {
-		pr_crit("CPU: %sTCM was detected %dk but expected %dk!\n",
-		       type ? "I" : "D",
-		       tcm_size,
-		       expected_size);
-		/* Adjust to the expected size? what can we do... */
-	}
+	/* Not much fun you can do with a size 0 bank */
+	if (tcm_size == 0)
+		return 0;
 
 	/* Force move the TCM bank to where we want it, enable */
-	tcm_region = offset | (tcm_region & 0x00000ffeU) | 1;
+	tcm_region = *offset | (tcm_region & 0x00000ffeU) | 1;
 
 	if (!type)
 		asm("mcr	p15, 0, %0, c9, c1, 0"
@@ -141,10 +164,15 @@ static void __init setup_tcm_bank(u8 type, u32 offset, u32 expected_size)
 		    : /* No output operands */
 		    : "r" (tcm_region));
 
-	pr_debug("CPU: moved %sTCM %dk to %08x, enabled\n",
-		 type ? "I" : "D",
-		 tcm_size,
-		 (tcm_region & 0xfffff000U));
+	/* Increase offset */
+	*offset += (tcm_size << 10);
+
+	pr_info("CPU: moved %sTCM%d %dk to %08x, enabled\n",
+		type ? "I" : "D",
+		bank,
+		tcm_size,
+		(tcm_region & 0xfffff000U));
+	return 0;
 }
 
 /*
@@ -152,37 +180,100 @@ static void __init setup_tcm_bank(u8 type, u32 offset, u32 expected_size)
  */
 void __init tcm_init(void)
 {
-	u32 tcm_status = read_cpuid_tcmstatus();
+	u32 tcm_status;
+	u8 dtcm_banks;
+	u8 itcm_banks;
+	size_t dtcm_code_sz = &__edtcm_data - &__sdtcm_data;
+	size_t itcm_code_sz = &__eitcm_text - &__sitcm_text;
 	char *start;
 	char *end;
 	char *ram;
+	int ret;
+	int i;
+
+	/*
+	 * Prior to ARMv5 there is no TCM, and trying to read the status
+	 * register will hang the processor.
+	 */
+	if (cpu_architecture() < CPU_ARCH_ARMv5) {
+		if (dtcm_code_sz || itcm_code_sz)
+			pr_info("CPU TCM: %u bytes of DTCM and %u bytes of "
+				"ITCM code compiled in, but no TCM present "
+				"in pre-v5 CPU\n", dtcm_code_sz, itcm_code_sz);
+		return;
+	}
+
+	tcm_status = read_cpuid_tcmstatus();
+	dtcm_banks = (tcm_status >> 16) & 0x03;
+	itcm_banks = (tcm_status & 0x03);
+
+	/* Values greater than 2 for D/ITCM banks are "reserved" */
+	if (dtcm_banks > 2)
+		dtcm_banks = 0;
+	if (itcm_banks > 2)
+		itcm_banks = 0;
 
 	/* Setup DTCM if present */
-	if (tcm_status & (1 << 16)) {
-		setup_tcm_bank(0, DTCM_OFFSET,
-			       (DTCM_END - DTCM_OFFSET + 1) >> 10);
+	if (dtcm_banks > 0) {
+		for (i = 0; i < dtcm_banks; i++) {
+			ret = setup_tcm_bank(0, i, dtcm_banks, &dtcm_end);
+			if (ret)
+				return;
+		}
+		/* This means you compiled more code than fits into DTCM */
+		if (dtcm_code_sz > (dtcm_end - DTCM_OFFSET)) {
+			pr_info("CPU DTCM: %u bytes of code compiled to "
+				"DTCM but only %lu bytes of DTCM present\n",
+				dtcm_code_sz, (dtcm_end - DTCM_OFFSET));
+			goto no_dtcm;
+		}
+		dtcm_res.end = dtcm_end - 1;
 		request_resource(&iomem_resource, &dtcm_res);
+		dtcm_iomap[0].length = dtcm_end - DTCM_OFFSET;
 		iotable_init(dtcm_iomap, 1);
 		/* Copy data from RAM to DTCM */
 		start = &__sdtcm_data;
 		end   = &__edtcm_data;
 		ram   = &__dtcm_start;
-		memcpy(start, ram, (end-start));
-		pr_debug("CPU DTCM: copied data from %p - %p\n", start, end);
+		memcpy(start, ram, dtcm_code_sz);
+		pr_debug("CPU DTCM: copied data from %p - %p\n",
+			 start, end);
+		dtcm_present = true;
+	} else if (dtcm_code_sz) {
+		pr_info("CPU DTCM: %u bytes of code compiled to DTCM but no "
+			"DTCM banks present in CPU\n", dtcm_code_sz);
 	}
 
+no_dtcm:
 	/* Setup ITCM if present */
-	if (tcm_status & 1) {
-		setup_tcm_bank(1, ITCM_OFFSET,
-			       (ITCM_END - ITCM_OFFSET + 1) >> 10);
+	if (itcm_banks > 0) {
+		for (i = 0; i < itcm_banks; i++) {
+			ret = setup_tcm_bank(1, i, itcm_banks, &itcm_end);
+			if (ret)
+				return;
+		}
+		/* This means you compiled more code than fits into ITCM */
+		if (itcm_code_sz > (itcm_end - ITCM_OFFSET)) {
+			pr_info("CPU ITCM: %u bytes of code compiled to "
+				"ITCM but only %lu bytes of ITCM present\n",
+				itcm_code_sz, (itcm_end - ITCM_OFFSET));
+			return;
+		}
+		itcm_res.end = itcm_end - 1;
 		request_resource(&iomem_resource, &itcm_res);
+		itcm_iomap[0].length = itcm_end - ITCM_OFFSET;
 		iotable_init(itcm_iomap, 1);
 		/* Copy code from RAM to ITCM */
 		start = &__sitcm_text;
 		end   = &__eitcm_text;
 		ram   = &__itcm_start;
-		memcpy(start, ram, (end-start));
-		pr_debug("CPU ITCM: copied code from %p - %p\n", start, end);
+		memcpy(start, ram, itcm_code_sz);
+		pr_debug("CPU ITCM: copied code from %p - %p\n",
+			 start, end);
+		itcm_present = true;
+	} else if (itcm_code_sz) {
+		pr_info("CPU ITCM: %u bytes of code compiled to ITCM but no "
+			"ITCM banks present in CPU\n", itcm_code_sz);
 	}
 }
 
@@ -193,7 +284,6 @@ void __init tcm_init(void)
  */
 static int __init setup_tcm_pool(void)
 {
-	u32 tcm_status = read_cpuid_tcmstatus();
 	u32 dtcm_pool_start = (u32) &__edtcm_data;
 	u32 itcm_pool_start = (u32) &__eitcm_text;
 	int ret;
@@ -208,10 +298,10 @@ static int __init setup_tcm_pool(void)
 	pr_debug("Setting up TCM memory pool\n");
 
 	/* Add the rest of DTCM to the TCM pool */
-	if (tcm_status & (1 << 16)) {
-		if (dtcm_pool_start < DTCM_END) {
+	if (dtcm_present) {
+		if (dtcm_pool_start < dtcm_end) {
 			ret = gen_pool_add(tcm_pool, dtcm_pool_start,
-					   DTCM_END - dtcm_pool_start + 1, -1);
+					   dtcm_end - dtcm_pool_start, -1);
 			if (ret) {
 				pr_err("CPU DTCM: could not add DTCM " \
 				       "remainder to pool!\n");
@@ -219,16 +309,16 @@ static int __init setup_tcm_pool(void)
 			}
 			pr_debug("CPU DTCM: Added %08x bytes @ %08x to " \
 				 "the TCM memory pool\n",
-				 DTCM_END - dtcm_pool_start + 1,
+				 dtcm_end - dtcm_pool_start,
 				 dtcm_pool_start);
 		}
 	}
 
 	/* Add the rest of ITCM to the TCM pool */
-	if (tcm_status & 1) {
-		if (itcm_pool_start < ITCM_END) {
+	if (itcm_present) {
+		if (itcm_pool_start < itcm_end) {
 			ret = gen_pool_add(tcm_pool, itcm_pool_start,
-					   ITCM_END - itcm_pool_start + 1, -1);
+					   itcm_end - itcm_pool_start, -1);
 			if (ret) {
 				pr_err("CPU ITCM: could not add ITCM " \
 				       "remainder to pool!\n");
@@ -236,7 +326,7 @@ static int __init setup_tcm_pool(void)
 			}
 			pr_debug("CPU ITCM: Added %08x bytes @ %08x to " \
 				 "the TCM memory pool\n",
-				 ITCM_END - itcm_pool_start + 1,
+				 itcm_end - itcm_pool_start,
 				 itcm_pool_start);
 		}
 	}