Blackfin: add some isram-driver self tests

Make it easy to figure out if code changes here are correct.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

2 files changed, 216 insertions, 2 deletions

diff --git a/arch/blackfin/Kconfig.debug b/arch/blackfin/Kconfig.debug
index 1fc4981d486f..87f195ee2e06 100644
--- a/arch/blackfin/Kconfig.debug
+++ b/arch/blackfin/Kconfig.debug
@@ -252,4 +252,10 @@ config ACCESS_CHECK
 
           Say N here to disable that check to improve the performance.
 
+config BFIN_ISRAM_SELF_TEST
+        bool "isram boot self tests"
+        default n
+        help
+          Run some self tests of the isram driver code at boot.
+
 endmenu
diff --git a/arch/blackfin/mm/isram-driver.c b/arch/blackfin/mm/isram-driver.c
index c080e70f98b0..02eaaa641d49 100644
--- a/arch/blackfin/mm/isram-driver.c
+++ b/arch/blackfin/mm/isram-driver.c
@@ -16,6 +16,8 @@
  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  */
 
+#define pr_fmt(fmt) "isram: " fmt
+
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/types.h>
@@ -23,6 +25,7 @@
 #include <linux/sched.h>
 
 #include <asm/blackfin.h>
+#include <asm/dma.h>
 
 /*
  * IMPORTANT WARNING ABOUT THESE FUNCTIONS
@@ -127,8 +130,7 @@ static bool isram_check_addr(const void *addr, size_t n)
             (addr < (void *)(L1_CODE_START + L1_CODE_LENGTH))) {
                 if ((addr + n) > (void *)(L1_CODE_START + L1_CODE_LENGTH)) {
                         show_stack(NULL, NULL);
-                        printk(KERN_ERR "isram_memcpy: copy involving %p length "
-                                        "(%zu) too long\n", addr, n);
+                        pr_err("copy involving %p length (%zu) too long\n", addr, n);
                 }
                 return true;
         }
@@ -199,3 +201,209 @@ void *isram_memcpy(void *dest, const void *src, size_t n)
 }
 EXPORT_SYMBOL(isram_memcpy);
 
+#ifdef CONFIG_BFIN_ISRAM_SELF_TEST
+
+#define TEST_LEN 0x100
+
+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;
+        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 (memcmp(&data1, &data2, sizeof(uint64_t))) {
+                        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;
+
+        /* 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 (memcmp(&data1, &data2, sizeof(uint64_t))) {
+                        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");
+
+        for (i = 0; i < TEST_LEN; ++i)
+                sdram[i] = i;
+        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;
+
+        sdram = kmalloc(TEST_LEN * 2, GFP_KERNEL);
+        if (!sdram) {
+                pr_warning("SKIP: could not allocate sdram\n");
+                return 0;
+        }
+
+        l1inst = l1_inst_sram_alloc(TEST_LEN);
+        if (!l1inst) {
+                kfree(sdram);
+                pr_warning("SKIP: could not allocate L1 inst\n");
+                return 0;
+        }
+
+        /* sanity check initial L1 inst state */
+        ret = 1;
+        pr_info("INFO: running initial dma_memcpy checks\n");
+        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