linux/arch/arm/mach-shmobile/setup-rcar-gen2.c

202 lines
4.9 KiB
C

/*
* R-Car Generation 2 support
*
* Copyright (C) 2013 Renesas Solutions Corp.
* Copyright (C) 2013 Magnus Damm
* Copyright (C) 2014 Ulrich Hecht
*
* 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 <linux/clk/shmobile.h>
#include <linux/clocksource.h>
#include <linux/device.h>
#include <linux/dma-contiguous.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/memblock.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <asm/mach/arch.h>
#include "common.h"
#include "rcar-gen2.h"
#define MODEMR 0xe6160060
u32 rcar_gen2_read_mode_pins(void)
{
static u32 mode;
static bool mode_valid;
if (!mode_valid) {
void __iomem *modemr = ioremap_nocache(MODEMR, 4);
BUG_ON(!modemr);
mode = ioread32(modemr);
iounmap(modemr);
mode_valid = true;
}
return mode;
}
#define CNTCR 0
#define CNTFID0 0x20
void __init rcar_gen2_timer_init(void)
{
u32 mode = rcar_gen2_read_mode_pins();
#ifdef CONFIG_ARM_ARCH_TIMER
void __iomem *base;
int extal_mhz = 0;
u32 freq;
if (of_machine_is_compatible("renesas,r8a7794")) {
freq = 260000000 / 8; /* ZS / 8 */
/* CNTVOFF has to be initialized either from non-secure
* Hypervisor mode or secure Monitor mode with SCR.NS==1.
* If TrustZone is enabled then it should be handled by the
* secure code.
*/
asm volatile(
" cps 0x16\n"
" mrc p15, 0, r1, c1, c1, 0\n"
" orr r0, r1, #1\n"
" mcr p15, 0, r0, c1, c1, 0\n"
" isb\n"
" mov r0, #0\n"
" mcrr p15, 4, r0, r0, c14\n"
" isb\n"
" mcr p15, 0, r1, c1, c1, 0\n"
" isb\n"
" cps 0x13\n"
: : : "r0", "r1");
} else {
/* At Linux boot time the r8a7790 arch timer comes up
* with the counter disabled. Moreover, it may also report
* a potentially incorrect fixed 13 MHz frequency. To be
* correct these registers need to be updated to use the
* frequency EXTAL / 2 which can be determined by the MD pins.
*/
switch (mode & (MD(14) | MD(13))) {
case 0:
extal_mhz = 15;
break;
case MD(13):
extal_mhz = 20;
break;
case MD(14):
extal_mhz = 26;
break;
case MD(13) | MD(14):
extal_mhz = 30;
break;
}
/* The arch timer frequency equals EXTAL / 2 */
freq = extal_mhz * (1000000 / 2);
}
/* Remap "armgcnt address map" space */
base = ioremap(0xe6080000, PAGE_SIZE);
/*
* Update the timer if it is either not running, or is not at the
* right frequency. The timer is only configurable in secure mode
* so this avoids an abort if the loader started the timer and
* entered the kernel in non-secure mode.
*/
if ((ioread32(base + CNTCR) & 1) == 0 ||
ioread32(base + CNTFID0) != freq) {
/* Update registers with correct frequency */
iowrite32(freq, base + CNTFID0);
asm volatile("mcr p15, 0, %0, c14, c0, 0" : : "r" (freq));
/* make sure arch timer is started by setting bit 0 of CNTCR */
iowrite32(1, base + CNTCR);
}
iounmap(base);
#endif /* CONFIG_ARM_ARCH_TIMER */
rcar_gen2_clocks_init(mode);
clocksource_of_init();
}
struct memory_reserve_config {
u64 reserved;
u64 base, size;
};
static int __init rcar_gen2_scan_mem(unsigned long node, const char *uname,
int depth, void *data)
{
const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
const __be32 *reg, *endp;
int l;
struct memory_reserve_config *mrc = data;
u64 lpae_start = 1ULL << 32;
/* We are scanning "memory" nodes only */
if (type == NULL || strcmp(type, "memory"))
return 0;
reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
if (reg == NULL)
reg = of_get_flat_dt_prop(node, "reg", &l);
if (reg == NULL)
return 0;
endp = reg + (l / sizeof(__be32));
while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
u64 base, size;
base = dt_mem_next_cell(dt_root_addr_cells, &reg);
size = dt_mem_next_cell(dt_root_size_cells, &reg);
if (base >= lpae_start)
continue;
if ((base + size) >= lpae_start)
size = lpae_start - base;
if (size < mrc->reserved)
continue;
if (base < mrc->base)
continue;
/* keep the area at top near the 32-bit legacy limit */
mrc->base = base + size - mrc->reserved;
mrc->size = mrc->reserved;
}
return 0;
}
struct cma *rcar_gen2_dma_contiguous;
void __init rcar_gen2_reserve(void)
{
struct memory_reserve_config mrc;
/* reserve 256 MiB at the top of the physical legacy 32-bit space */
memset(&mrc, 0, sizeof(mrc));
mrc.reserved = SZ_256M;
of_scan_flat_dt(rcar_gen2_scan_mem, &mrc);
#ifdef CONFIG_DMA_CMA
if (mrc.size && memblock_is_region_memory(mrc.base, mrc.size))
dma_contiguous_reserve_area(mrc.size, mrc.base, 0,
&rcar_gen2_dma_contiguous, true);
#endif
}