alistair23-linux/arch/arm/mach-keystone/keystone.c
Santosh Shilimkar 5eb3da7246 ARM: keystone: Switch over to coherent memory address space
With late code patching updates for LPAE machines has merged now and
memblock conversion from bootmem is on its way, Keystone can switch to
the coherent memory address space which starts beyond 4GB boundary.
The idmap alias needs are managed via virt_to_idmap() for boot purpose.

Tested-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
2014-05-08 15:43:33 -04:00

128 lines
3.4 KiB
C

/*
* Keystone2 based boards and SOC related code.
*
* Copyright 2013 Texas Instruments, Inc.
* Cyril Chemparathy <cyril@ti.com>
* Santosh Shilimkar <santosh.shillimkar@ti.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*/
#include <linux/io.h>
#include <linux/of.h>
#include <linux/init.h>
#include <linux/of_platform.h>
#include <linux/of_address.h>
#include <asm/setup.h>
#include <asm/mach/map.h>
#include <asm/mach/arch.h>
#include <asm/mach/time.h>
#include <asm/smp_plat.h>
#include <asm/memory.h>
#include "memory.h"
#include "keystone.h"
#define PLL_RESET_WRITE_KEY_MASK 0xffff0000
#define PLL_RESET_WRITE_KEY 0x5a69
#define PLL_RESET BIT(16)
static void __iomem *keystone_rstctrl;
static void __init keystone_init(void)
{
struct device_node *node;
node = of_find_compatible_node(NULL, NULL, "ti,keystone-reset");
if (WARN_ON(!node))
pr_warn("ti,keystone-reset node undefined\n");
keystone_rstctrl = of_iomap(node, 0);
if (WARN_ON(!keystone_rstctrl))
pr_warn("ti,keystone-reset iomap error\n");
keystone_pm_runtime_init();
of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
}
static phys_addr_t keystone_virt_to_idmap(unsigned long x)
{
return (phys_addr_t)(x) - CONFIG_PAGE_OFFSET + KEYSTONE_LOW_PHYS_START;
}
static void __init keystone_init_meminfo(void)
{
bool lpae = IS_ENABLED(CONFIG_ARM_LPAE);
bool pvpatch = IS_ENABLED(CONFIG_ARM_PATCH_PHYS_VIRT);
phys_addr_t offset = PHYS_OFFSET - KEYSTONE_LOW_PHYS_START;
phys_addr_t mem_start, mem_end;
BUG_ON(meminfo.nr_banks < 1);
mem_start = meminfo.bank[0].start;
mem_end = mem_start + meminfo.bank[0].size - 1;
/* nothing to do if we are running out of the <32-bit space */
if (mem_start >= KEYSTONE_LOW_PHYS_START &&
mem_end <= KEYSTONE_LOW_PHYS_END)
return;
if (!lpae || !pvpatch) {
pr_crit("Enable %s%s%s to run outside 32-bit space\n",
!lpae ? __stringify(CONFIG_ARM_LPAE) : "",
(!lpae && !pvpatch) ? " and " : "",
!pvpatch ? __stringify(CONFIG_ARM_PATCH_PHYS_VIRT) : "");
}
if (mem_start < KEYSTONE_HIGH_PHYS_START ||
mem_end > KEYSTONE_HIGH_PHYS_END) {
pr_crit("Invalid address space for memory (%08llx-%08llx)\n",
(u64)mem_start, (u64)mem_end);
}
offset += KEYSTONE_HIGH_PHYS_START;
__pv_phys_pfn_offset = PFN_DOWN(offset);
__pv_offset = (offset - PAGE_OFFSET);
/* Populate the arch idmap hook */
arch_virt_to_idmap = keystone_virt_to_idmap;
pr_info("Switching to high address space at 0x%llx\n", (u64)offset);
}
static const char *keystone_match[] __initconst = {
"ti,keystone",
NULL,
};
void keystone_restart(enum reboot_mode mode, const char *cmd)
{
u32 val;
BUG_ON(!keystone_rstctrl);
/* Enable write access to RSTCTRL */
val = readl(keystone_rstctrl);
val &= PLL_RESET_WRITE_KEY_MASK;
val |= PLL_RESET_WRITE_KEY;
writel(val, keystone_rstctrl);
/* Reset the SOC */
val = readl(keystone_rstctrl);
val &= ~PLL_RESET;
writel(val, keystone_rstctrl);
}
DT_MACHINE_START(KEYSTONE, "Keystone")
#if defined(CONFIG_ZONE_DMA) && defined(CONFIG_ARM_LPAE)
.dma_zone_size = SZ_2G,
#endif
.smp = smp_ops(keystone_smp_ops),
.init_machine = keystone_init,
.dt_compat = keystone_match,
.restart = keystone_restart,
.init_meminfo = keystone_init_meminfo,
MACHINE_END