From 77231330739962e4a76ae23f42a840558a0c675f Mon Sep 17 00:00:00 2001 From: Vladimir Serbinenko Date: Fri, 19 Feb 2016 22:50:50 +0100 Subject: [PATCH] qemu/vexpress-a9: Discover RAM size. Probe RAM to find its size instead of hardcoding 1024M. Also properly export it to memory map. Change-Id: Ib411f0a068bd247a9e0cd0a59689a3896921483e Signed-off-by: Vladimir Serbinenko Reviewed-on: https://review.coreboot.org/13754 Tested-by: build bot (Jenkins) Reviewed-by: Arthur Heymans --- src/mainboard/emulation/qemu-armv7/Kconfig | 4 -- src/mainboard/emulation/qemu-armv7/cbmem.c | 46 ++++++++++++++++++- .../emulation/qemu-armv7/mainboard.c | 40 ++++++++++++++++ .../emulation/qemu-armv7/mainboard.h | 23 ++++++++++ 4 files changed, 108 insertions(+), 5 deletions(-) create mode 100644 src/mainboard/emulation/qemu-armv7/mainboard.c create mode 100644 src/mainboard/emulation/qemu-armv7/mainboard.h diff --git a/src/mainboard/emulation/qemu-armv7/Kconfig b/src/mainboard/emulation/qemu-armv7/Kconfig index f7c4b2d862..76bdb321ea 100644 --- a/src/mainboard/emulation/qemu-armv7/Kconfig +++ b/src/mainboard/emulation/qemu-armv7/Kconfig @@ -49,8 +49,4 @@ config MAINBOARD_VENDOR string default "ARM Ltd." -config DRAM_SIZE_MB - int - default 1024 - endif # BOARD_EMULATION_QEMU_ARMV7 diff --git a/src/mainboard/emulation/qemu-armv7/cbmem.c b/src/mainboard/emulation/qemu-armv7/cbmem.c index a626ec6adf..f26ca6cd20 100644 --- a/src/mainboard/emulation/qemu-armv7/cbmem.c +++ b/src/mainboard/emulation/qemu-armv7/cbmem.c @@ -14,8 +14,52 @@ #include #include #include +#include +#include "mainboard.h" + +#define PATTERN1 0x55 +#define PATTERN2 0xaa + +/* Returns 1 if mebibyte mb is present and 0 otherwise. */ +static int probe_mb(int mb) +{ + char *ptr = (char *) 0x60000000 + (mb << 20) + 0xfffff; + char old; + if (ptr < (char *) &_eprogram) { + /* Don't probe below _end to avoid accidentally clobering + oneself. */ + return 1; + } + + old = read8(ptr); + write8(ptr, PATTERN1); + if (read8(ptr) != PATTERN1) + return 0; + write8(ptr, PATTERN2); + if (read8(ptr) != PATTERN2) + return 0; + write8(ptr, old); + return 1; +} + +int probe_ramsize(void) +{ + int i; + int discovered = 0; + static int saved_result; + if (saved_result) + return saved_result; + /* Compact binary search. */ + /* 1 GiB is the largest supported RAM by this machine. */ + for (i = 9; i >= 0; i--) + if (probe_mb(discovered | (1 << i))) + discovered |= (1 << i); + discovered++; + saved_result = discovered; + return discovered; +} void *cbmem_top(void) { - return _dram + (CONFIG_DRAM_SIZE_MB << 20); + return _dram + (probe_ramsize() << 20); } diff --git a/src/mainboard/emulation/qemu-armv7/mainboard.c b/src/mainboard/emulation/qemu-armv7/mainboard.c new file mode 100644 index 0000000000..eced9ae3b9 --- /dev/null +++ b/src/mainboard/emulation/qemu-armv7/mainboard.c @@ -0,0 +1,40 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (C) 2016 Vladimir Serbinenko + * + * 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; version 2 or, at your option, any later + * version of the License. + * + * 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. + */ + +#include +#include +#include +#include +#include +#include "mainboard.h" + +static void mainboard_enable(device_t dev) +{ + int discovered; + if (!dev) { + printk(BIOS_EMERG, "No dev0; die\n"); + halt(); + } + + discovered = probe_ramsize(); + printk(BIOS_DEBUG, "%d MiB of RAM discovered\n", discovered); + ram_resource(dev, 0, 0x60000000 >> 10, discovered << 10); + cbmem_recovery(0); +} + +struct chip_operations mainboard_ops = { + .enable_dev = mainboard_enable, +}; diff --git a/src/mainboard/emulation/qemu-armv7/mainboard.h b/src/mainboard/emulation/qemu-armv7/mainboard.h new file mode 100644 index 0000000000..87fa3beee6 --- /dev/null +++ b/src/mainboard/emulation/qemu-armv7/mainboard.h @@ -0,0 +1,23 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (C) 2016 Vladimir Serbinenko + * + * 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; version 2 or, at your option, any later + * version of the License. + * + * 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. + */ + +#ifndef QEMU_ARMV7_MAINBOARD_H +#define QEMU_ARMV7_MAINBOARD_H + +/* Returns RAM size in mebibytes. */ +int probe_ramsize(void); + +#endif