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Diffstat (limited to 'board/trab/memory.c')
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diff --git a/board/trab/memory.c b/board/trab/memory.c new file mode 100755 index 0000000..9104413 --- /dev/null +++ b/board/trab/memory.c @@ -0,0 +1,485 @@ +/* + * (C) Copyright 2002-2003 + * Wolfgang Denk, DENX Software Engineering, wd@denx.de. + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <common.h> + +/* Memory test + * + * General observations: + * o The recommended test sequence is to test the data lines: if they are + * broken, nothing else will work properly. Then test the address + * lines. Finally, test the cells in the memory now that the test + * program knows that the address and data lines work properly. + * This sequence also helps isolate and identify what is faulty. + * + * o For the address line test, it is a good idea to use the base + * address of the lowest memory location, which causes a '1' bit to + * walk through a field of zeros on the address lines and the highest + * memory location, which causes a '0' bit to walk through a field of + * '1's on the address line. + * + * o Floating buses can fool memory tests if the test routine writes + * a value and then reads it back immediately. The problem is, the + * write will charge the residual capacitance on the data bus so the + * bus retains its state briefely. When the test program reads the + * value back immediately, the capacitance of the bus can allow it + * to read back what was written, even though the memory circuitry + * is broken. To avoid this, the test program should write a test + * pattern to the target location, write a different pattern elsewhere + * to charge the residual capacitance in a differnt manner, then read + * the target location back. + * + * o Always read the target location EXACTLY ONCE and save it in a local + * variable. The problem with reading the target location more than + * once is that the second and subsequent reads may work properly, + * resulting in a failed test that tells the poor technician that + * "Memory error at 00000000, wrote aaaaaaaa, read aaaaaaaa" which + * doesn't help him one bit and causes puzzled phone calls. Been there, + * done that. + * + * Data line test: + * --------------- + * This tests data lines for shorts and opens by forcing adjacent data + * to opposite states. Because the data lines could be routed in an + * arbitrary manner the must ensure test patterns ensure that every case + * is tested. By using the following series of binary patterns every + * combination of adjacent bits is test regardless of routing. + * + * ...101010101010101010101010 + * ...110011001100110011001100 + * ...111100001111000011110000 + * ...111111110000000011111111 + * + * Carrying this out, gives us six hex patterns as follows: + * + * 0xaaaaaaaaaaaaaaaa + * 0xcccccccccccccccc + * 0xf0f0f0f0f0f0f0f0 + * 0xff00ff00ff00ff00 + * 0xffff0000ffff0000 + * 0xffffffff00000000 + * + * To test for short and opens to other signals on our boards, we + * simply test with the 1's complemnt of the paterns as well, resulting + * in twelve patterns total. + * + * After writing a test pattern. a special pattern 0x0123456789ABCDEF is + * written to a different address in case the data lines are floating. + * Thus, if a byte lane fails, you will see part of the special + * pattern in that byte lane when the test runs. For example, if the + * xx__xxxxxxxxxxxx byte line fails, you will see aa23aaaaaaaaaaaa + * (for the 'a' test pattern). + * + * Address line test: + * ------------------ + * This function performs a test to verify that all the address lines + * hooked up to the RAM work properly. If there is an address line + * fault, it usually shows up as two different locations in the address + * map (related by the faulty address line) mapping to one physical + * memory storage location. The artifact that shows up is writing to + * the first location "changes" the second location. + * + * To test all address lines, we start with the given base address and + * xor the address with a '1' bit to flip one address line. For each + * test, we shift the '1' bit left to test the next address line. + * + * In the actual code, we start with address sizeof(ulong) since our + * test pattern we use is a ulong and thus, if we tried to test lower + * order address bits, it wouldn't work because our pattern would + * overwrite itself. + * + * Example for a 4 bit address space with the base at 0000: + * 0000 <- base + * 0001 <- test 1 + * 0010 <- test 2 + * 0100 <- test 3 + * 1000 <- test 4 + * Example for a 4 bit address space with the base at 0010: + * 0010 <- base + * 0011 <- test 1 + * 0000 <- (below the base address, skipped) + * 0110 <- test 2 + * 1010 <- test 3 + * + * The test locations are successively tested to make sure that they are + * not "mirrored" onto the base address due to a faulty address line. + * Note that the base and each test location are related by one address + * line flipped. Note that the base address need not be all zeros. + * + * Memory tests 1-4: + * ----------------- + * These tests verify RAM using sequential writes and reads + * to/from RAM. There are several test cases that use different patterns to + * verify RAM. Each test case fills a region of RAM with one pattern and + * then reads the region back and compares its contents with the pattern. + * The following patterns are used: + * + * 1a) zero pattern (0x00000000) + * 1b) negative pattern (0xffffffff) + * 1c) checkerboard pattern (0x55555555) + * 1d) checkerboard pattern (0xaaaaaaaa) + * 2) bit-flip pattern ((1 << (offset % 32)) + * 3) address pattern (offset) + * 4) address pattern (~offset) + * + * Being run in normal mode, the test verifies only small 4Kb + * regions of RAM around each 1Mb boundary. For example, for 64Mb + * RAM the following areas are verified: 0x00000000-0x00000800, + * 0x000ff800-0x00100800, 0x001ff800-0x00200800, ..., 0x03fff800- + * 0x04000000. If the test is run in slow-test mode, it verifies + * the whole RAM. + */ + +/* #ifdef CONFIG_POST */ + +#include <post.h> +#include <watchdog.h> + +/* #if CONFIG_POST & CFG_POST_MEMORY */ + +/* + * Define INJECT_*_ERRORS for testing error detection in the presence of + * _good_ hardware. + */ +#undef INJECT_DATA_ERRORS +#undef INJECT_ADDRESS_ERRORS + +#ifdef INJECT_DATA_ERRORS +#warning "Injecting data line errors for testing purposes" +#endif + +#ifdef INJECT_ADDRESS_ERRORS +#warning "Injecting address line errors for testing purposes" +#endif + + +/* + * This function performs a double word move from the data at + * the source pointer to the location at the destination pointer. + * This is helpful for testing memory on processors which have a 64 bit + * wide data bus. + * + * On those PowerPC with FPU, use assembly and a floating point move: + * this does a 64 bit move. + * + * For other processors, let the compiler generate the best code it can. + */ +static void move64(unsigned long long *src, unsigned long long *dest) +{ +#if defined(CONFIG_MPC8260) || defined(CONFIG_MPC824X) + asm ("lfd 0, 0(3)\n\t" /* fpr0 = *scr */ + "stfd 0, 0(4)" /* *dest = fpr0 */ + : : : "fr0" ); /* Clobbers fr0 */ + return; +#else + *dest = *src; +#endif +} + +/* + * This is 64 bit wide test patterns. Note that they reside in ROM + * (which presumably works) and the tests write them to RAM which may + * not work. + * + * The "otherpattern" is written to drive the data bus to values other + * than the test pattern. This is for detecting floating bus lines. + * + */ +const static unsigned long long pattern[] = { + 0xaaaaaaaaaaaaaaaaULL, + 0xccccccccccccccccULL, + 0xf0f0f0f0f0f0f0f0ULL, + 0xff00ff00ff00ff00ULL, + 0xffff0000ffff0000ULL, + 0xffffffff00000000ULL, + 0x00000000ffffffffULL, + 0x0000ffff0000ffffULL, + 0x00ff00ff00ff00ffULL, + 0x0f0f0f0f0f0f0f0fULL, + 0x3333333333333333ULL, + 0x5555555555555555ULL, +}; +const unsigned long long otherpattern = 0x0123456789abcdefULL; + + +static int memory_post_dataline(unsigned long long * pmem) +{ + unsigned long long temp64; + int num_patterns = sizeof(pattern)/ sizeof(pattern[0]); + int i; + unsigned int hi, lo, pathi, patlo; + int ret = 0; + + for ( i = 0; i < num_patterns; i++) { + move64((unsigned long long *)&(pattern[i]), pmem++); + /* + * Put a different pattern on the data lines: otherwise they + * may float long enough to read back what we wrote. + */ + move64((unsigned long long *)&otherpattern, pmem--); + move64(pmem, &temp64); + +#ifdef INJECT_DATA_ERRORS + temp64 ^= 0x00008000; +#endif + + if (temp64 != pattern[i]){ + pathi = (pattern[i]>>32) & 0xffffffff; + patlo = pattern[i] & 0xffffffff; + + hi = (temp64>>32) & 0xffffffff; + lo = temp64 & 0xffffffff; + + printf ("Memory (date line) error at %08lx, " + "wrote %08x%08x, read %08x%08x !\n", + (ulong)pmem, pathi, patlo, hi, lo); + ret = -1; + } + } + return ret; +} + +static int memory_post_addrline(ulong *testaddr, ulong *base, ulong size) +{ + ulong *target; + ulong *end; + ulong readback; + ulong xor; + int ret = 0; + + end = (ulong *)((ulong)base + size); /* pointer arith! */ + xor = 0; + for(xor = sizeof(ulong); xor > 0; xor <<= 1) { + target = (ulong *)((ulong)testaddr ^ xor); + if((target >= base) && (target < end)) { + *testaddr = ~*target; + readback = *target; + +#ifdef INJECT_ADDRESS_ERRORS + if(xor == 0x00008000) { + readback = *testaddr; + } +#endif + if(readback == *testaddr) { + printf ("Memory (address line) error at %08lx<->%08lx, " + "XOR value %08lx !\n", + (ulong)testaddr, (ulong)target, + xor); + ret = -1; + } + } + } + return ret; +} + +static int memory_post_test1 (unsigned long start, + unsigned long size, + unsigned long val) +{ + unsigned long i; + ulong *mem = (ulong *) start; + ulong readback; + int ret = 0; + + for (i = 0; i < size / sizeof (ulong); i++) { + mem[i] = val; + if (i % 1024 == 0) + WATCHDOG_RESET (); + } + + for (i = 0; i < size / sizeof (ulong) && ret == 0; i++) { + readback = mem[i]; + if (readback != val) { + printf ("Memory error at %08lx, " + "wrote %08lx, read %08lx !\n", + (ulong)(mem + i), val, readback); + + ret = -1; + break; + } + if (i % 1024 == 0) + WATCHDOG_RESET (); + } + + return ret; +} + +static int memory_post_test2 (unsigned long start, unsigned long size) +{ + unsigned long i; + ulong *mem = (ulong *) start; + ulong readback; + int ret = 0; + + for (i = 0; i < size / sizeof (ulong); i++) { + mem[i] = 1 << (i % 32); + if (i % 1024 == 0) + WATCHDOG_RESET (); + } + + for (i = 0; i < size / sizeof (ulong) && ret == 0; i++) { + readback = mem[i]; + if (readback != (1 << (i % 32))) { + printf ("Memory error at %08lx, " + "wrote %08x, read %08lx !\n", + (ulong)(mem + i), 1 << (i % 32), readback); + + ret = -1; + break; + } + if (i % 1024 == 0) + WATCHDOG_RESET (); + } + + return ret; +} + +static int memory_post_test3 (unsigned long start, unsigned long size) +{ + unsigned long i; + ulong *mem = (ulong *) start; + ulong readback; + int ret = 0; + + for (i = 0; i < size / sizeof (ulong); i++) { + mem[i] = i; + if (i % 1024 == 0) + WATCHDOG_RESET (); + } + + for (i = 0; i < size / sizeof (ulong) && ret == 0; i++) { + readback = mem[i]; + if (readback != i) { + printf ("Memory error at %08lx, " + "wrote %08lx, read %08lx !\n", + (ulong)(mem + i), i, readback); + + ret = -1; + break; + } + if (i % 1024 == 0) + WATCHDOG_RESET (); + } + + return ret; +} + +static int memory_post_test4 (unsigned long start, unsigned long size) +{ + unsigned long i; + ulong *mem = (ulong *) start; + ulong readback; + int ret = 0; + + for (i = 0; i < size / sizeof (ulong); i++) { + mem[i] = ~i; + if (i % 1024 == 0) + WATCHDOG_RESET (); + } + + for (i = 0; i < size / sizeof (ulong) && ret == 0; i++) { + readback = mem[i]; + if (readback != ~i) { + printf ("Memory error at %08lx, " + "wrote %08lx, read %08lx !\n", + (ulong)(mem + i), ~i, readback); + + ret = -1; + break; + } + if (i % 1024 == 0) + WATCHDOG_RESET (); + } + + return ret; +} + +int memory_post_tests (unsigned long start, unsigned long size) +{ + int ret = 0; + + if (ret == 0) + ret = memory_post_dataline ((long long *)start); + WATCHDOG_RESET (); + if (ret == 0) + ret = memory_post_addrline ((long *)start, (long *)start, size); + WATCHDOG_RESET (); + if (ret == 0) + ret = memory_post_addrline ((long *)(start + size - 8), + (long *)start, size); + WATCHDOG_RESET (); + if (ret == 0) + ret = memory_post_test1 (start, size, 0x00000000); + WATCHDOG_RESET (); + if (ret == 0) + ret = memory_post_test1 (start, size, 0xffffffff); + WATCHDOG_RESET (); + if (ret == 0) + ret = memory_post_test1 (start, size, 0x55555555); + WATCHDOG_RESET (); + if (ret == 0) + ret = memory_post_test1 (start, size, 0xaaaaaaaa); + WATCHDOG_RESET (); + if (ret == 0) + ret = memory_post_test2 (start, size); + WATCHDOG_RESET (); + if (ret == 0) + ret = memory_post_test3 (start, size); + WATCHDOG_RESET (); + if (ret == 0) + ret = memory_post_test4 (start, size); + WATCHDOG_RESET (); + + return ret; +} + +#if 0 +int memory_post_test (int flags) +{ + int ret = 0; + DECLARE_GLOBAL_DATA_PTR; + bd_t *bd = gd->bd; + unsigned long memsize = (bd->bi_memsize >= 256 << 20 ? + 256 << 20 : bd->bi_memsize) - (1 << 20); + + + if (flags & POST_SLOWTEST) { + ret = memory_post_tests (CFG_SDRAM_BASE, memsize); + } else { /* POST_NORMAL */ + + unsigned long i; + + for (i = 0; i < (memsize >> 20) && ret == 0; i++) { + if (ret == 0) + ret = memory_post_tests (i << 20, 0x800); + if (ret == 0) + ret = memory_post_tests ((i << 20) + 0xff800, 0x800); + } + } + + return ret; +} +#endif /* 0 */ + +/* #endif */ /* CONFIG_POST & CFG_POST_MEMORY */ +/* #endif */ /* CONFIG_POST */ |