forked from Minki/linux
ba56a9876d
Initial commit for a new SoC family, UniPhier, developed by Socionext Inc. (formerly, System LSI Business Division of Panasonic Corporation). This commit includes a minimal set of components for booting the kernel, including SMP support. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
91 lines
2.2 KiB
C
91 lines
2.2 KiB
C
/*
|
|
* Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com>
|
|
*
|
|
* 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; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* 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/sizes.h>
|
|
#include <linux/compiler.h>
|
|
#include <linux/init.h>
|
|
#include <linux/io.h>
|
|
#include <linux/regmap.h>
|
|
#include <linux/mfd/syscon.h>
|
|
#include <asm/smp.h>
|
|
#include <asm/smp_scu.h>
|
|
|
|
static struct regmap *sbcm_regmap;
|
|
|
|
static void __init uniphier_smp_prepare_cpus(unsigned int max_cpus)
|
|
{
|
|
static cpumask_t only_cpu_0 = { CPU_BITS_CPU0 };
|
|
unsigned long scu_base_phys = 0;
|
|
void __iomem *scu_base;
|
|
|
|
sbcm_regmap = syscon_regmap_lookup_by_compatible(
|
|
"socionext,uniphier-system-bus-controller-misc");
|
|
if (IS_ERR(sbcm_regmap)) {
|
|
pr_err("failed to regmap system-bus-controller-misc\n");
|
|
goto err;
|
|
}
|
|
|
|
if (scu_a9_has_base())
|
|
scu_base_phys = scu_a9_get_base();
|
|
|
|
if (!scu_base_phys) {
|
|
pr_err("failed to get scu base\n");
|
|
goto err;
|
|
}
|
|
|
|
scu_base = ioremap(scu_base_phys, SZ_128);
|
|
if (!scu_base) {
|
|
pr_err("failed to remap scu base (0x%08lx)\n", scu_base_phys);
|
|
goto err;
|
|
}
|
|
|
|
scu_enable(scu_base);
|
|
iounmap(scu_base);
|
|
|
|
return;
|
|
err:
|
|
pr_warn("disabling SMP\n");
|
|
init_cpu_present(&only_cpu_0);
|
|
sbcm_regmap = NULL;
|
|
}
|
|
|
|
static void __naked uniphier_secondary_startup(void)
|
|
{
|
|
asm("bl v7_invalidate_l1\n"
|
|
"b secondary_startup\n");
|
|
};
|
|
|
|
static int uniphier_boot_secondary(unsigned int cpu,
|
|
struct task_struct *idle)
|
|
{
|
|
int ret;
|
|
|
|
if (!sbcm_regmap)
|
|
return -ENODEV;
|
|
|
|
ret = regmap_write(sbcm_regmap, 0x1208,
|
|
virt_to_phys(uniphier_secondary_startup));
|
|
if (!ret)
|
|
asm("sev"); /* wake up secondary CPU */
|
|
|
|
return ret;
|
|
}
|
|
|
|
struct smp_operations uniphier_smp_ops __initdata = {
|
|
.smp_prepare_cpus = uniphier_smp_prepare_cpus,
|
|
.smp_boot_secondary = uniphier_boot_secondary,
|
|
};
|
|
CPU_METHOD_OF_DECLARE(uniphier_smp, "socionext,uniphier-smp",
|
|
&uniphier_smp_ops);
|