Nicolas Le Bayon | 620ce33 | 2021-03-02 11:19:36 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2022, STMicroelectronics - All Rights Reserved |
| 3 | * |
| 4 | * SPDX-License-Identifier: BSD-3-Clause |
| 5 | */ |
| 6 | |
| 7 | #include <drivers/st/stm32mp_ddr_test.h> |
| 8 | #include <lib/mmio.h> |
| 9 | |
| 10 | #include <platform_def.h> |
| 11 | |
| 12 | #define DDR_PATTERN 0xAAAAAAAAU |
| 13 | #define DDR_ANTIPATTERN 0x55555555U |
| 14 | |
| 15 | /******************************************************************************* |
| 16 | * This function tests a simple read/write access to the DDR. |
| 17 | * Note that the previous content is restored after test. |
| 18 | * Returns 0 if success, and address value else. |
| 19 | ******************************************************************************/ |
| 20 | uint32_t stm32mp_ddr_test_rw_access(void) |
| 21 | { |
| 22 | uint32_t saved_value = mmio_read_32(STM32MP_DDR_BASE); |
| 23 | |
| 24 | mmio_write_32(STM32MP_DDR_BASE, DDR_PATTERN); |
| 25 | |
| 26 | if (mmio_read_32(STM32MP_DDR_BASE) != DDR_PATTERN) { |
| 27 | return (uint32_t)STM32MP_DDR_BASE; |
| 28 | } |
| 29 | |
| 30 | mmio_write_32(STM32MP_DDR_BASE, saved_value); |
| 31 | |
| 32 | return 0U; |
| 33 | } |
| 34 | |
| 35 | /******************************************************************************* |
| 36 | * This function tests the DDR data bus wiring. |
| 37 | * This is inspired from the Data Bus Test algorithm written by Michael Barr |
| 38 | * in "Programming Embedded Systems in C and C++" book. |
| 39 | * resources.oreilly.com/examples/9781565923546/blob/master/Chapter6/ |
| 40 | * File: memtest.c - This source code belongs to Public Domain. |
| 41 | * Returns 0 if success, and address value else. |
| 42 | ******************************************************************************/ |
| 43 | uint32_t stm32mp_ddr_test_data_bus(void) |
| 44 | { |
| 45 | uint32_t pattern; |
| 46 | |
| 47 | for (pattern = 1U; pattern != 0U; pattern <<= 1U) { |
| 48 | mmio_write_32(STM32MP_DDR_BASE, pattern); |
| 49 | |
| 50 | if (mmio_read_32(STM32MP_DDR_BASE) != pattern) { |
| 51 | return (uint32_t)STM32MP_DDR_BASE; |
| 52 | } |
| 53 | } |
| 54 | |
| 55 | return 0; |
| 56 | } |
| 57 | |
| 58 | /******************************************************************************* |
| 59 | * This function tests the DDR address bus wiring. |
| 60 | * This is inspired from the Data Bus Test algorithm written by Michael Barr |
| 61 | * in "Programming Embedded Systems in C and C++" book. |
| 62 | * resources.oreilly.com/examples/9781565923546/blob/master/Chapter6/ |
| 63 | * File: memtest.c - This source code belongs to Public Domain. |
| 64 | * size: size in bytes of the DDR memory device. |
| 65 | * Returns 0 if success, and address value else. |
| 66 | ******************************************************************************/ |
| 67 | uint32_t stm32mp_ddr_test_addr_bus(uint64_t size) |
| 68 | { |
| 69 | uint64_t addressmask = size - 1U; |
| 70 | uint64_t offset; |
| 71 | uint64_t testoffset = 0U; |
| 72 | |
| 73 | /* Write the default pattern at each of the power-of-two offsets. */ |
| 74 | for (offset = sizeof(uint32_t); (offset & addressmask) != 0U; |
| 75 | offset <<= 1U) { |
| 76 | mmio_write_32(STM32MP_DDR_BASE + (uint32_t)offset, |
| 77 | DDR_PATTERN); |
| 78 | } |
| 79 | |
| 80 | /* Check for address bits stuck high. */ |
| 81 | mmio_write_32(STM32MP_DDR_BASE + (uint32_t)testoffset, |
| 82 | DDR_ANTIPATTERN); |
| 83 | |
| 84 | for (offset = sizeof(uint32_t); (offset & addressmask) != 0U; |
| 85 | offset <<= 1U) { |
| 86 | if (mmio_read_32(STM32MP_DDR_BASE + (uint32_t)offset) != |
| 87 | DDR_PATTERN) { |
| 88 | return (uint32_t)(STM32MP_DDR_BASE + offset); |
| 89 | } |
| 90 | } |
| 91 | |
| 92 | mmio_write_32(STM32MP_DDR_BASE + (uint32_t)testoffset, DDR_PATTERN); |
| 93 | |
| 94 | /* Check for address bits stuck low or shorted. */ |
| 95 | for (testoffset = sizeof(uint32_t); (testoffset & addressmask) != 0U; |
| 96 | testoffset <<= 1U) { |
| 97 | mmio_write_32(STM32MP_DDR_BASE + (uint32_t)testoffset, |
| 98 | DDR_ANTIPATTERN); |
| 99 | |
| 100 | if (mmio_read_32(STM32MP_DDR_BASE) != DDR_PATTERN) { |
| 101 | return STM32MP_DDR_BASE; |
| 102 | } |
| 103 | |
| 104 | for (offset = sizeof(uint32_t); (offset & addressmask) != 0U; |
| 105 | offset <<= 1) { |
| 106 | if ((mmio_read_32(STM32MP_DDR_BASE + |
| 107 | (uint32_t)offset) != DDR_PATTERN) && |
| 108 | (offset != testoffset)) { |
| 109 | return (uint32_t)(STM32MP_DDR_BASE + offset); |
| 110 | } |
| 111 | } |
| 112 | |
| 113 | mmio_write_32(STM32MP_DDR_BASE + (uint32_t)testoffset, |
| 114 | DDR_PATTERN); |
| 115 | } |
| 116 | |
| 117 | return 0U; |
| 118 | } |
| 119 | |
| 120 | /******************************************************************************* |
| 121 | * This function checks the DDR size. It has to be run with Data Cache off. |
| 122 | * This test is run before data have been put in DDR, and is only done for |
| 123 | * cold boot. The DDR data can then be overwritten, and it is not useful to |
| 124 | * restore its content. |
| 125 | * Returns DDR computed size. |
| 126 | ******************************************************************************/ |
| 127 | uint32_t stm32mp_ddr_check_size(void) |
| 128 | { |
| 129 | uint32_t offset = sizeof(uint32_t); |
| 130 | |
| 131 | mmio_write_32(STM32MP_DDR_BASE, DDR_PATTERN); |
| 132 | |
| 133 | while (offset < STM32MP_DDR_MAX_SIZE) { |
| 134 | mmio_write_32(STM32MP_DDR_BASE + offset, DDR_ANTIPATTERN); |
| 135 | dsb(); |
| 136 | |
| 137 | if (mmio_read_32(STM32MP_DDR_BASE) != DDR_PATTERN) { |
| 138 | break; |
| 139 | } |
| 140 | |
| 141 | offset <<= 1U; |
| 142 | } |
| 143 | |
| 144 | INFO("Memory size = 0x%x (%u MB)\n", offset, offset / (1024U * 1024U)); |
| 145 | |
| 146 | return offset; |
| 147 | } |