coreboot-kgpe-d16/src/soc/imgtec/pistachio/bootblock.c
Ionela Voinescu 56e64598a2 imgtec/pistachio: identity map SOC registers region
This region must be mapped uncached. This is necesary for an
U-boot payload which will obtain all register base addresses
as physical addresses from the device tree and will use them
as such.

Change-Id: Ib5041df7d90c6ef61b7448a18dd732afbd9489ca
Signed-off-by: Ionela Voinescu <ionela.voinescu@imgtec.com>
Reviewed-on: https://review.coreboot.org/12770
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2015-12-31 17:34:28 +01:00

62 lines
1.7 KiB
C

/*
* This file is part of the coreboot project.
*
* Copyright (C) 2014 Imagination Technologies
*
* 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 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 <arch/cpu.h>
#include <arch/mmu.h>
#include <assert.h>
#include <stdint.h>
#include <symbols.h>
static void bootblock_cpu_init(void)
{
uint32_t cause;
/*
* Make sure the count register is counting by clearing the "Disable
* Counter" bit, in case it is set.
*/
cause = read_c0_cause();
if (cause & C0_CAUSE_DC)
write_c0_cause(cause & ~(C0_CAUSE_DC));
/* And make sure that it starts from zero. */
write_c0_count(0);
}
static void bootblock_mmu_init(void)
{
uint32_t null_guard_size = 1 * MiB;
uint32_t dram_base, dram_size;
write_c0_wired(0);
dram_base = (uint32_t)_dram;
dram_size = CONFIG_DRAM_SIZE_MB * MiB;
/*
* To be able to catch NULL pointer dereference attempts, lets not map
* memory close to zero.
*/
if (dram_base < null_guard_size) {
dram_base += null_guard_size;
dram_size -= null_guard_size;
}
assert(!identity_map((uint32_t)_sram, _sram_size,
C0_ENTRYLO_COHERENCY_WB));
assert(!identity_map(dram_base, dram_size, C0_ENTRYLO_COHERENCY_WB));
assert(!identity_map((uint32_t)_soc_registers, _soc_registers_size,
C0_ENTRYLO_COHERENCY_UC));
}