Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 410 insertions, 0 deletions

diff --git a/kernel/arch/blackfin/mm/isram-driver.c b/kernel/arch/blackfin/mm/isram-driver.c
new file mode 100644
index 000000000..7e2e674ed
--- /dev/null
+++ b/kernel/arch/blackfin/mm/isram-driver.c
@@ -0,0 +1,410 @@
+/*
+ * Instruction SRAM accessor functions for the Blackfin
+ *
+ * Copyright 2008 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later
+ */
+
+#define pr_fmt(fmt) "isram: " fmt
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/sched.h>
+
+#include <asm/blackfin.h>
+#include <asm/dma.h>
+
+/*
+ * IMPORTANT WARNING ABOUT THESE FUNCTIONS
+ *
+ * The emulator will not function correctly if a write command is left in
+ * ITEST_COMMAND or DTEST_COMMAND AND access to cache memory is needed by
+ * the emulator. To avoid such problems, ensure that both ITEST_COMMAND
+ * and DTEST_COMMAND are zero when exiting these functions.
+ */
+
+
+/*
+ * On the Blackfin, L1 instruction sram (which operates at core speeds) can not
+ * be accessed by a normal core load, so we need to go through a few hoops to
+ * read/write it.
+ * To try to make it easier - we export a memcpy interface, where either src or
+ * dest can be in this special L1 memory area.
+ * The low level read/write functions should not be exposed to the rest of the
+ * kernel, since they operate on 64-bit data, and need specific address alignment
+ */
+
+static DEFINE_SPINLOCK(dtest_lock);
+
+/* Takes a void pointer */
+#define IADDR2DTEST(x) \
+	({ unsigned long __addr = (unsigned long)(x); \
+		((__addr & (1 << 11)) << (26 - 11)) | /* addr bit 11 (Way0/Way1)   */ \
+		(1 << 24)                           | /* instruction access = 1    */ \
+		((__addr & (1 << 15)) << (23 - 15)) | /* addr bit 15 (Data Bank)   */ \
+		((__addr & (3 << 12)) << (16 - 12)) | /* addr bits 13:12 (Subbank) */ \
+		(__addr & 0x47F8)                   | /* addr bits 14 & 10:3       */ \
+		(1 << 2);                             /* data array = 1            */ \
+	})
+
+/* Takes a pointer, and returns the offset (in bits) which things should be shifted */
+#define ADDR2OFFSET(x) ((((unsigned long)(x)) & 0x7) * 8)
+
+/* Takes a pointer, determines if it is the last byte in the isram 64-bit data type */
+#define ADDR2LAST(x) ((((unsigned long)x) & 0x7) == 0x7)
+
+static void isram_write(const void *addr, uint64_t data)
+{
+	uint32_t cmd;
+	unsigned long flags;
+
+	if (unlikely(addr >= (void *)(L1_CODE_START + L1_CODE_LENGTH)))
+		return;
+
+	cmd = IADDR2DTEST(addr) | 2;             /* write */
+
+	/*
+	 * Writes to DTEST_DATA[0:1] need to be atomic with write to DTEST_COMMAND
+	 * While in exception context - atomicity is guaranteed or double fault
+	 */
+	spin_lock_irqsave(&dtest_lock, flags);
+
+	bfin_write_DTEST_DATA0(data & 0xFFFFFFFF);
+	bfin_write_DTEST_DATA1(data >> 32);
+
+	/* use the builtin, since interrupts are already turned off */
+	__builtin_bfin_csync();
+	bfin_write_DTEST_COMMAND(cmd);
+	__builtin_bfin_csync();
+
+	bfin_write_DTEST_COMMAND(0);
+	__builtin_bfin_csync();
+
+	spin_unlock_irqrestore(&dtest_lock, flags);
+}
+
+static uint64_t isram_read(const void *addr)
+{
+	uint32_t cmd;
+	unsigned long flags;
+	uint64_t ret;
+
+	if (unlikely(addr > (void *)(L1_CODE_START + L1_CODE_LENGTH)))
+		return 0;
+
+	cmd = IADDR2DTEST(addr) | 0;              /* read */
+
+	/*
+	 * Reads of DTEST_DATA[0:1] need to be atomic with write to DTEST_COMMAND
+	 * While in exception context - atomicity is guaranteed or double fault
+	 */
+	spin_lock_irqsave(&dtest_lock, flags);
+	/* use the builtin, since interrupts are already turned off */
+	__builtin_bfin_csync();
+	bfin_write_DTEST_COMMAND(cmd);
+	__builtin_bfin_csync();
+	ret = bfin_read_DTEST_DATA0() | ((uint64_t)bfin_read_DTEST_DATA1() << 32);
+
+	bfin_write_DTEST_COMMAND(0);
+	__builtin_bfin_csync();
+	spin_unlock_irqrestore(&dtest_lock, flags);
+
+	return ret;
+}
+
+static bool isram_check_addr(const void *addr, size_t n)
+{
+	if ((addr >= (void *)L1_CODE_START) &&
+	    (addr < (void *)(L1_CODE_START + L1_CODE_LENGTH))) {
+		if (unlikely((addr + n) > (void *)(L1_CODE_START + L1_CODE_LENGTH))) {
+			show_stack(NULL, NULL);
+			pr_err("copy involving %p length (%zu) too long\n", addr, n);
+		}
+		return true;
+	}
+	return false;
+}
+
+/*
+ * The isram_memcpy() function copies n bytes from memory area src to memory area dest.
+ * The isram_memcpy() function returns a pointer to dest.
+ * Either dest or src can be in L1 instruction sram.
+ */
+void *isram_memcpy(void *dest, const void *src, size_t n)
+{
+	uint64_t data_in = 0, data_out = 0;
+	size_t count;
+	bool dest_in_l1, src_in_l1, need_data, put_data;
+	unsigned char byte, *src_byte, *dest_byte;
+
+	src_byte = (unsigned char *)src;
+	dest_byte = (unsigned char *)dest;
+
+	dest_in_l1 = isram_check_addr(dest, n);
+	src_in_l1 = isram_check_addr(src, n);
+
+	need_data = true;
+	put_data = true;
+	for (count = 0; count < n; count++) {
+		if (src_in_l1) {
+			if (need_data) {
+				data_in = isram_read(src + count);
+				need_data = false;
+			}
+
+			if (ADDR2LAST(src + count))
+				need_data = true;
+
+			byte = (unsigned char)((data_in >> ADDR2OFFSET(src + count)) & 0xff);
+
+		} else {
+			/* src is in L2 or L3 - so just dereference*/
+			byte = src_byte[count];
+		}
+
+		if (dest_in_l1) {
+			if (put_data) {
+				data_out = isram_read(dest + count);
+				put_data = false;
+			}
+
+			data_out &= ~((uint64_t)0xff << ADDR2OFFSET(dest + count));
+			data_out |= ((uint64_t)byte << ADDR2OFFSET(dest + count));
+
+			if (ADDR2LAST(dest + count)) {
+				put_data = true;
+				isram_write(dest + count, data_out);
+			}
+		} else {
+			/* dest in L2 or L3 - so just dereference */
+			dest_byte[count] = byte;
+		}
+	}
+
+	/* make sure we dump the last byte if necessary */
+	if (dest_in_l1 && !put_data)
+		isram_write(dest + count, data_out);
+
+	return dest;
+}
+EXPORT_SYMBOL(isram_memcpy);
+
+#ifdef CONFIG_BFIN_ISRAM_SELF_TEST
+
+static int test_len = 0x20000;
+
+static __init void hex_dump(unsigned char *buf, int len)
+{
+	while (len--)
+		pr_cont("%02x", *buf++);
+}
+
+static __init int isram_read_test(char *sdram, void *l1inst)
+{
+	int i, ret = 0;
+	uint64_t data1, data2;
+
+	pr_info("INFO: running isram_read tests\n");
+
+	/* setup some different data to play with */
+	for (i = 0; i < test_len; ++i)
+		sdram[i] = i % 255;
+	dma_memcpy(l1inst, sdram, test_len);
+
+	/* make sure we can read the L1 inst */
+	for (i = 0; i < test_len; i += sizeof(uint64_t)) {
+		data1 = isram_read(l1inst + i);
+		memcpy(&data2, sdram + i, sizeof(data2));
+		if (data1 != data2) {
+			pr_err("FAIL: isram_read(%p) returned %#llx but wanted %#llx\n",
+				l1inst + i, data1, data2);
+			++ret;
+		}
+	}
+
+	return ret;
+}
+
+static __init int isram_write_test(char *sdram, void *l1inst)
+{
+	int i, ret = 0;
+	uint64_t data1, data2;
+
+	pr_info("INFO: running isram_write tests\n");
+
+	/* setup some different data to play with */
+	memset(sdram, 0, test_len * 2);
+	dma_memcpy(l1inst, sdram, test_len);
+	for (i = 0; i < test_len; ++i)
+		sdram[i] = i % 255;
+
+	/* make sure we can write the L1 inst */
+	for (i = 0; i < test_len; i += sizeof(uint64_t)) {
+		memcpy(&data1, sdram + i, sizeof(data1));
+		isram_write(l1inst + i, data1);
+		data2 = isram_read(l1inst + i);
+		if (data1 != data2) {
+			pr_err("FAIL: isram_write(%p, %#llx) != %#llx\n",
+				l1inst + i, data1, data2);
+			++ret;
+		}
+	}
+
+	dma_memcpy(sdram + test_len, l1inst, test_len);
+	if (memcmp(sdram, sdram + test_len, test_len)) {
+		pr_err("FAIL: isram_write() did not work properly\n");
+		++ret;
+	}
+
+	return ret;
+}
+
+static __init int
+_isram_memcpy_test(char pattern, void *sdram, void *l1inst, const char *smemcpy,
+                   void *(*fmemcpy)(void *, const void *, size_t))
+{
+	memset(sdram, pattern, test_len);
+	fmemcpy(l1inst, sdram, test_len);
+	fmemcpy(sdram + test_len, l1inst, test_len);
+	if (memcmp(sdram, sdram + test_len, test_len)) {
+		pr_err("FAIL: %s(%p <=> %p, %#x) failed (data is %#x)\n",
+			smemcpy, l1inst, sdram, test_len, pattern);
+		return 1;
+	}
+	return 0;
+}
+#define _isram_memcpy_test(a, b, c, d) _isram_memcpy_test(a, b, c, #d, d)
+
+static __init int isram_memcpy_test(char *sdram, void *l1inst)
+{
+	int i, j, thisret, ret = 0;
+
+	/* check broad isram_memcpy() */
+	pr_info("INFO: running broad isram_memcpy tests\n");
+	for (i = 0xf; i >= 0; --i)
+		ret += _isram_memcpy_test(i, sdram, l1inst, isram_memcpy);
+
+	/* check read of small, unaligned, and hardware 64bit limits */
+	pr_info("INFO: running isram_memcpy (read) tests\n");
+
+	/* setup some different data to play with */
+	for (i = 0; i < test_len; ++i)
+		sdram[i] = i % 255;
+	dma_memcpy(l1inst, sdram, test_len);
+
+	thisret = 0;
+	for (i = 0; i < test_len - 32; ++i) {
+		unsigned char cmp[32];
+		for (j = 1; j <= 32; ++j) {
+			memset(cmp, 0, sizeof(cmp));
+			isram_memcpy(cmp, l1inst + i, j);
+			if (memcmp(cmp, sdram + i, j)) {
+				pr_err("FAIL: %p:", l1inst + 1);
+				hex_dump(cmp, j);
+				pr_cont(" SDRAM:");
+				hex_dump(sdram + i, j);
+				pr_cont("\n");
+				if (++thisret > 20) {
+					pr_err("FAIL: skipping remaining series\n");
+					i = test_len;
+					break;
+				}
+			}
+		}
+	}
+	ret += thisret;
+
+	/* check write of small, unaligned, and hardware 64bit limits */
+	pr_info("INFO: running isram_memcpy (write) tests\n");
+
+	memset(sdram + test_len, 0, test_len);
+	dma_memcpy(l1inst, sdram + test_len, test_len);
+
+	thisret = 0;
+	for (i = 0; i < test_len - 32; ++i) {
+		unsigned char cmp[32];
+		for (j = 1; j <= 32; ++j) {
+			isram_memcpy(l1inst + i, sdram + i, j);
+			dma_memcpy(cmp, l1inst + i, j);
+			if (memcmp(cmp, sdram + i, j)) {
+				pr_err("FAIL: %p:", l1inst + i);
+				hex_dump(cmp, j);
+				pr_cont(" SDRAM:");
+				hex_dump(sdram + i, j);
+				pr_cont("\n");
+				if (++thisret > 20) {
+					pr_err("FAIL: skipping remaining series\n");
+					i = test_len;
+					break;
+				}
+			}
+		}
+	}
+	ret += thisret;
+
+	return ret;
+}
+
+static __init int isram_test_init(void)
+{
+	int ret;
+	char *sdram;
+	void *l1inst;
+
+	/* Try to test as much of L1SRAM as possible */
+	while (test_len) {
+		test_len >>= 1;
+		l1inst = l1_inst_sram_alloc(test_len);
+		if (l1inst)
+			break;
+	}
+	if (!l1inst) {
+		pr_warning("SKIP: could not allocate L1 inst\n");
+		return 0;
+	}
+	pr_info("INFO: testing %#x bytes (%p - %p)\n",
+	        test_len, l1inst, l1inst + test_len);
+
+	sdram = kmalloc(test_len * 2, GFP_KERNEL);
+	if (!sdram) {
+		sram_free(l1inst);
+		pr_warning("SKIP: could not allocate sdram\n");
+		return 0;
+	}
+
+	/* sanity check initial L1 inst state */
+	ret = 1;
+	pr_info("INFO: running initial dma_memcpy checks %p\n", sdram);
+	if (_isram_memcpy_test(0xa, sdram, l1inst, dma_memcpy))
+		goto abort;
+	if (_isram_memcpy_test(0x5, sdram, l1inst, dma_memcpy))
+		goto abort;
+
+	ret = 0;
+	ret += isram_read_test(sdram, l1inst);
+	ret += isram_write_test(sdram, l1inst);
+	ret += isram_memcpy_test(sdram, l1inst);
+
+ abort:
+	sram_free(l1inst);
+	kfree(sdram);
+
+	if (ret)
+		return -EIO;
+
+	pr_info("PASS: all tests worked !\n");
+	return 0;
+}
+late_initcall(isram_test_init);
+
+static __exit void isram_test_exit(void)
+{
+	/* stub to allow unloading */
+}
+module_exit(isram_test_exit);
+
+#endif