From 102b0d2daa97dae68d3eed54d8fe37a9cc38a892 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 28 Apr 2024 11:13:47 +0200 Subject: Adding upstream version 2.8.0+dfsg. Signed-off-by: Daniel Baumann --- drivers/st/ddr/stm32mp_ddr_test.c | 148 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 148 insertions(+) create mode 100644 drivers/st/ddr/stm32mp_ddr_test.c (limited to 'drivers/st/ddr/stm32mp_ddr_test.c') diff --git a/drivers/st/ddr/stm32mp_ddr_test.c b/drivers/st/ddr/stm32mp_ddr_test.c new file mode 100644 index 0000000..6733cc6 --- /dev/null +++ b/drivers/st/ddr/stm32mp_ddr_test.c @@ -0,0 +1,148 @@ +/* + * Copyright (C) 2022, STMicroelectronics - All Rights Reserved + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include +#include +#include + +#include + +#define DDR_PATTERN 0xAAAAAAAAU +#define DDR_ANTIPATTERN 0x55555555U + +/******************************************************************************* + * This function tests a simple read/write access to the DDR. + * Note that the previous content is restored after test. + * Returns 0 if success, and address value else. + ******************************************************************************/ +uint32_t stm32mp_ddr_test_rw_access(void) +{ + uint32_t saved_value = mmio_read_32(STM32MP_DDR_BASE); + + mmio_write_32(STM32MP_DDR_BASE, DDR_PATTERN); + + if (mmio_read_32(STM32MP_DDR_BASE) != DDR_PATTERN) { + return (uint32_t)STM32MP_DDR_BASE; + } + + mmio_write_32(STM32MP_DDR_BASE, saved_value); + + return 0U; +} + +/******************************************************************************* + * This function tests the DDR data bus wiring. + * This is inspired from the Data Bus Test algorithm written by Michael Barr + * in "Programming Embedded Systems in C and C++" book. + * resources.oreilly.com/examples/9781565923546/blob/master/Chapter6/ + * File: memtest.c - This source code belongs to Public Domain. + * Returns 0 if success, and address value else. + ******************************************************************************/ +uint32_t stm32mp_ddr_test_data_bus(void) +{ + uint32_t pattern; + + for (pattern = 1U; pattern != 0U; pattern <<= 1U) { + mmio_write_32(STM32MP_DDR_BASE, pattern); + + if (mmio_read_32(STM32MP_DDR_BASE) != pattern) { + return (uint32_t)STM32MP_DDR_BASE; + } + } + + return 0; +} + +/******************************************************************************* + * This function tests the DDR address bus wiring. + * This is inspired from the Data Bus Test algorithm written by Michael Barr + * in "Programming Embedded Systems in C and C++" book. + * resources.oreilly.com/examples/9781565923546/blob/master/Chapter6/ + * File: memtest.c - This source code belongs to Public Domain. + * size: size in bytes of the DDR memory device. + * Returns 0 if success, and address value else. + ******************************************************************************/ +uint32_t stm32mp_ddr_test_addr_bus(uint64_t size) +{ + uint64_t addressmask = size - 1U; + uint64_t offset; + uint64_t testoffset = 0U; + + /* Write the default pattern at each of the power-of-two offsets. */ + for (offset = sizeof(uint32_t); (offset & addressmask) != 0U; + offset <<= 1U) { + mmio_write_32(STM32MP_DDR_BASE + (uint32_t)offset, + DDR_PATTERN); + } + + /* Check for address bits stuck high. */ + mmio_write_32(STM32MP_DDR_BASE + (uint32_t)testoffset, + DDR_ANTIPATTERN); + + for (offset = sizeof(uint32_t); (offset & addressmask) != 0U; + offset <<= 1U) { + if (mmio_read_32(STM32MP_DDR_BASE + (uint32_t)offset) != + DDR_PATTERN) { + return (uint32_t)(STM32MP_DDR_BASE + offset); + } + } + + mmio_write_32(STM32MP_DDR_BASE + (uint32_t)testoffset, DDR_PATTERN); + + /* Check for address bits stuck low or shorted. */ + for (testoffset = sizeof(uint32_t); (testoffset & addressmask) != 0U; + testoffset <<= 1U) { + mmio_write_32(STM32MP_DDR_BASE + (uint32_t)testoffset, + DDR_ANTIPATTERN); + + if (mmio_read_32(STM32MP_DDR_BASE) != DDR_PATTERN) { + return STM32MP_DDR_BASE; + } + + for (offset = sizeof(uint32_t); (offset & addressmask) != 0U; + offset <<= 1) { + if ((mmio_read_32(STM32MP_DDR_BASE + + (uint32_t)offset) != DDR_PATTERN) && + (offset != testoffset)) { + return (uint32_t)(STM32MP_DDR_BASE + offset); + } + } + + mmio_write_32(STM32MP_DDR_BASE + (uint32_t)testoffset, + DDR_PATTERN); + } + + return 0U; +} + +/******************************************************************************* + * This function checks the DDR size. It has to be run with Data Cache off. + * This test is run before data have been put in DDR, and is only done for + * cold boot. The DDR data can then be overwritten, and it is not useful to + * restore its content. + * Returns DDR computed size. + ******************************************************************************/ +uint32_t stm32mp_ddr_check_size(void) +{ + uint32_t offset = sizeof(uint32_t); + + mmio_write_32(STM32MP_DDR_BASE, DDR_PATTERN); + + while (offset < STM32MP_DDR_MAX_SIZE) { + mmio_write_32(STM32MP_DDR_BASE + offset, DDR_ANTIPATTERN); + dsb(); + + if (mmio_read_32(STM32MP_DDR_BASE) != DDR_PATTERN) { + break; + } + + offset <<= 1U; + } + + INFO("Memory size = 0x%x (%u MB)\n", offset, offset / (1024U * 1024U)); + + return offset; +} -- cgit v1.2.3