Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 434 insertions, 0 deletions

diff --git a/arch/arm/kernel/tcm.c b/arch/arm/kernel/tcm.c
new file mode 100644
index 000000000..b10e13607
--- /dev/null
+++ b/arch/arm/kernel/tcm.c
@@ -0,0 +1,434 @@
+/*
+ * Copyright (C) 2008-2009 ST-Ericsson AB
+ * License terms: GNU General Public License (GPL) version 2
+ * TCM memory handling for ARM systems
+ *
+ * Author: Linus Walleij <linus.walleij@stericsson.com>
+ * Author: Rickard Andersson <rickard.andersson@stericsson.com>
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/stddef.h>
+#include <linux/ioport.h>
+#include <linux/genalloc.h>
+#include <linux/string.h> /* memcpy */
+#include <asm/cputype.h>
+#include <asm/mach/map.h>
+#include <asm/memory.h>
+#include <asm/system_info.h>
+#include <asm/traps.h>
+
+#define TCMTR_FORMAT_MASK	0xe0000000U
+
+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_OFFSET,
+	.flags = IORESOURCE_MEM
+};
+
+static struct resource itcm_res = {
+	.name = "ITCM RAM",
+	.start = ITCM_OFFSET,
+	.end = ITCM_OFFSET,
+	.flags = IORESOURCE_MEM
+};
+
+static struct map_desc dtcm_iomap[] __initdata = {
+	{
+		.virtual	= DTCM_OFFSET,
+		.pfn		= __phys_to_pfn(DTCM_OFFSET),
+		.length		= 0,
+		.type		= MT_MEMORY_RW_DTCM
+	}
+};
+
+static struct map_desc itcm_iomap[] __initdata = {
+	{
+		.virtual	= ITCM_OFFSET,
+		.pfn		= __phys_to_pfn(ITCM_OFFSET),
+		.length		= 0,
+		.type		= MT_MEMORY_RWX_ITCM,
+	}
+};
+
+/*
+ * Allocate a chunk of TCM memory
+ */
+void *tcm_alloc(size_t len)
+{
+	unsigned long vaddr;
+
+	if (!tcm_pool)
+		return NULL;
+
+	vaddr = gen_pool_alloc(tcm_pool, len);
+	if (!vaddr)
+		return NULL;
+
+	return (void *) vaddr;
+}
+EXPORT_SYMBOL(tcm_alloc);
+
+/*
+ * Free a chunk of TCM memory
+ */
+void tcm_free(void *addr, size_t len)
+{
+	gen_pool_free(tcm_pool, (unsigned long) addr, 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 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"
+		    : "=r" (tcm_region));
+	else
+		asm("mrc	p15, 0, %0, c9, c1, 1"
+		    : "=r" (tcm_region));
+
+	tcm_size = tcm_sizes[(tcm_region >> 2) & 0x0f];
+	if (tcm_size < 0) {
+		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%d %dk @ %08x, %senabled\n",
+			type ? "I" : "D",
+			bank,
+			tcm_size,
+			(tcm_region & 0xfffff000U),
+			(tcm_region & 1) ? "" : "not ");
+	}
+
+	/* 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;
+
+	if (!type)
+		asm("mcr	p15, 0, %0, c9, c1, 0"
+		    : /* No output operands */
+		    : "r" (tcm_region));
+	else
+		asm("mcr	p15, 0, %0, c9, c1, 1"
+		    : /* No output operands */
+		    : "r" (tcm_region));
+
+	/* 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;
+}
+
+/*
+ * When we are running in the non-secure world and the secure world
+ * has not explicitly given us access to the TCM we will get an
+ * undefined error when reading the TCM region register in the
+ * setup_tcm_bank function (above).
+ *
+ * There are two variants of this register read that we need to trap,
+ * the read for the data TCM and the read for the instruction TCM:
+ *  c0370628:       ee196f11        mrc     15, 0, r6, cr9, cr1, {0}
+ *  c0370674:       ee196f31        mrc     15, 0, r6, cr9, cr1, {1}
+ *
+ * Our undef hook mask explicitly matches all fields of the encoded
+ * instruction other than the destination register.  The mask also
+ * only allows operand 2 to have the values 0 or 1.
+ *
+ * The undefined hook is defined as __init and __initdata, and therefore
+ * must be removed before tcm_init returns.
+ *
+ * In this particular case (MRC with ARM condition code ALways) the
+ * Thumb-2 and ARM instruction encoding are identical, so this hook
+ * will work on a Thumb-2 kernel.
+ *
+ * See A8.8.107, DDI0406C_C ARM Architecture Reference Manual, Encoding
+ * T1/A1 for the bit-by-bit details.
+ *
+ *  mrc   p15, 0, XX, c9, c1, 0
+ *  mrc   p15, 0, XX, c9, c1, 1
+ *   |  |  |   |   |   |   |  +---- opc2           0|1 = 000|001
+ *   |  |  |   |   |   |   +------- CRm              0 = 0001
+ *   |  |  |   |   |   +----------- CRn              0 = 1001
+ *   |  |  |   |   +--------------- Rt               ? = ????
+ *   |  |  |   +------------------- opc1             0 =  000
+ *   |  |  +----------------------- coproc          15 = 1111
+ *   |  +-------------------------- condition   ALways = 1110
+ *   +----------------------------- instruction    MRC = 1110
+ *
+ * Encoding this as per A8.8.107 of DDI0406C, Encoding T1/A1, yields:
+ *  1111 1111 1111 1111 0000 1111 1101 1111 Required Mask
+ *  1110 1110 0001 1001 ???? 1111 0001 0001 mrc p15, 0, XX, c9, c1, 0
+ *  1110 1110 0001 1001 ???? 1111 0011 0001 mrc p15, 0, XX, c9, c1, 1
+ *  [  ] [  ] [ ]| [  ] [  ] [  ] [ ]| +--- CRm
+ *    |    |   | |   |    |    |   | +----- SBO
+ *    |    |   | |   |    |    |   +------- opc2
+ *    |    |   | |   |    |    +----------- coproc
+ *    |    |   | |   |    +---------------- Rt
+ *    |    |   | |   +--------------------- CRn
+ *    |    |   | +------------------------- SBO
+ *    |    |   +--------------------------- opc1
+ *    |    +------------------------------- instruction
+ *    +------------------------------------ condition
+ */
+#define TCM_REGION_READ_MASK		0xffff0fdf
+#define TCM_REGION_READ_INSTR		0xee190f11
+#define DEST_REG_SHIFT			12
+#define DEST_REG_MASK			0xf
+
+static int __init tcm_handler(struct pt_regs *regs, unsigned int instr)
+{
+	regs->uregs[(instr >> DEST_REG_SHIFT) & DEST_REG_MASK] = 0;
+	regs->ARM_pc += 4;
+	return 0;
+}
+
+static struct undef_hook tcm_hook __initdata = {
+	.instr_mask	= TCM_REGION_READ_MASK,
+	.instr_val	= TCM_REGION_READ_INSTR,
+	.cpsr_mask	= MODE_MASK,
+	.cpsr_val	= SVC_MODE,
+	.fn		= tcm_handler
+};
+
+/*
+ * This initializes the TCM memory
+ */
+void __init tcm_init(void)
+{
+	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();
+
+	/*
+	 * This code only supports v6-compatible TCMTR implementations.
+	 */
+	if (tcm_status & TCMTR_FORMAT_MASK)
+		return;
+
+	dtcm_banks = (tcm_status >> 16) & 0x03;
+	itcm_banks = (tcm_status & 0x03);
+
+	register_undef_hook(&tcm_hook);
+
+	/* 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 (dtcm_banks > 0) {
+		for (i = 0; i < dtcm_banks; i++) {
+			ret = setup_tcm_bank(0, i, dtcm_banks, &dtcm_end);
+			if (ret)
+				goto unregister;
+		}
+		/* 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;
+		}
+		/*
+		 * This means that the DTCM sizes were 0 or the DTCM banks
+		 * were inaccessible due to TrustZone configuration.
+		 */
+		if (!(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, 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 (itcm_banks > 0) {
+		for (i = 0; i < itcm_banks; i++) {
+			ret = setup_tcm_bank(1, i, itcm_banks, &itcm_end);
+			if (ret)
+				goto unregister;
+		}
+		/* 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));
+			goto unregister;
+		}
+		/*
+		 * This means that the ITCM sizes were 0 or the ITCM banks
+		 * were inaccessible due to TrustZone configuration.
+		 */
+		if (!(itcm_end - ITCM_OFFSET))
+			goto unregister;
+		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, 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);
+	}
+
+unregister:
+	unregister_undef_hook(&tcm_hook);
+}
+
+/*
+ * This creates the TCM memory pool and has to be done later,
+ * during the core_initicalls, since the allocator is not yet
+ * up and running when the first initialization runs.
+ */
+static int __init setup_tcm_pool(void)
+{
+	u32 dtcm_pool_start = (u32) &__edtcm_data;
+	u32 itcm_pool_start = (u32) &__eitcm_text;
+	int ret;
+
+	/*
+	 * Set up malloc pool, 2^2 = 4 bytes granularity since
+	 * the TCM is sometimes just 4 KiB. NB: pages and cache
+	 * line alignments does not matter in TCM!
+	 */
+	tcm_pool = gen_pool_create(2, -1);
+
+	pr_debug("Setting up TCM memory pool\n");
+
+	/* Add the rest of DTCM to the TCM pool */
+	if (dtcm_present) {
+		if (dtcm_pool_start < dtcm_end) {
+			ret = gen_pool_add(tcm_pool, dtcm_pool_start,
+					   dtcm_end - dtcm_pool_start, -1);
+			if (ret) {
+				pr_err("CPU DTCM: could not add DTCM " \
+				       "remainder to pool!\n");
+				return ret;
+			}
+			pr_debug("CPU DTCM: Added %08x bytes @ %08x to " \
+				 "the TCM memory pool\n",
+				 dtcm_end - dtcm_pool_start,
+				 dtcm_pool_start);
+		}
+	}
+
+	/* Add the rest of ITCM to the TCM pool */
+	if (itcm_present) {
+		if (itcm_pool_start < itcm_end) {
+			ret = gen_pool_add(tcm_pool, itcm_pool_start,
+					   itcm_end - itcm_pool_start, -1);
+			if (ret) {
+				pr_err("CPU ITCM: could not add ITCM " \
+				       "remainder to pool!\n");
+				return ret;
+			}
+			pr_debug("CPU ITCM: Added %08x bytes @ %08x to " \
+				 "the TCM memory pool\n",
+				 itcm_end - itcm_pool_start,
+				 itcm_pool_start);
+		}
+	}
+	return 0;
+}
+
+core_initcall(setup_tcm_pool);