diff options
Diffstat (limited to 'arch/arm/mach-rockchip/platsmp.c')
| -rw-r--r-- | arch/arm/mach-rockchip/platsmp.c | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/arch/arm/mach-rockchip/platsmp.c b/arch/arm/mach-rockchip/platsmp.c new file mode 100644 index 000000000000..dbfa5a26cfff --- /dev/null +++ b/arch/arm/mach-rockchip/platsmp.c @@ -0,0 +1,184 @@ +/* + * Copyright (c) 2013 MundoReader S.L. + * Author: Heiko Stuebner <heiko@sntech.de> + * + * 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/delay.h> +#include <linux/init.h> +#include <linux/smp.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> + +#include <asm/cacheflush.h> +#include <asm/smp_scu.h> +#include <asm/smp_plat.h> +#include <asm/mach/map.h> + +#include "core.h" + +static void __iomem *scu_base_addr; +static void __iomem *sram_base_addr; +static int ncores; + +#define PMU_PWRDN_CON 0x08 +#define PMU_PWRDN_ST 0x0c + +#define PMU_PWRDN_SCU 4 + +static void __iomem *pmu_base_addr; + +static inline bool pmu_power_domain_is_on(int pd) +{ + return !(readl_relaxed(pmu_base_addr + PMU_PWRDN_ST) & BIT(pd)); +} + +static void pmu_set_power_domain(int pd, bool on) +{ + u32 val = readl_relaxed(pmu_base_addr + PMU_PWRDN_CON); + if (on) + val &= ~BIT(pd); + else + val |= BIT(pd); + writel(val, pmu_base_addr + PMU_PWRDN_CON); + + while (pmu_power_domain_is_on(pd) != on) { } +} + +/* + * Handling of CPU cores + */ + +static int __cpuinit rockchip_boot_secondary(unsigned int cpu, + struct task_struct *idle) +{ + if (!sram_base_addr || !pmu_base_addr) { + pr_err("%s: sram or pmu missing for cpu boot\n", __func__); + return -ENXIO; + } + + if (cpu >= ncores) { + pr_err("%s: cpu %d outside maximum number of cpus %d\n", + __func__, cpu, ncores); + return -ENXIO; + } + + /* start the core */ + pmu_set_power_domain(0 + cpu, true); + + return 0; +} + +/** + * rockchip_smp_prepare_sram - populate necessary sram block + * Starting cores execute the code residing at the start of the on-chip sram + * after power-on. Therefore make sure, this sram region is reserved and + * big enough. After this check, copy the trampoline code that directs the + * core to the real startup code in ram into the sram-region. + * @node: mmio-sram device node + */ +static int __init rockchip_smp_prepare_sram(struct device_node *node) +{ + unsigned int trampoline_sz = &rockchip_secondary_trampoline_end - + &rockchip_secondary_trampoline; + struct resource res; + unsigned int rsize; + int ret; + + ret = of_address_to_resource(node, 0, &res); + if (ret < 0) { + pr_err("%s: could not get address for node %s\n", + __func__, node->full_name); + return ret; + } + + rsize = resource_size(&res); + if (rsize < trampoline_sz) { + pr_err("%s: reserved block with size 0x%x is to small for trampoline size 0x%x\n", + __func__, rsize, trampoline_sz); + return -EINVAL; + } + + sram_base_addr = of_iomap(node, 0); + + /* set the boot function for the sram code */ + rockchip_boot_fn = virt_to_phys(rockchip_secondary_startup); + + /* copy the trampoline to sram, that runs during startup of the core */ + memcpy(sram_base_addr, &rockchip_secondary_trampoline, trampoline_sz); + flush_cache_all(); + outer_clean_range(0, trampoline_sz); + + dsb_sev(); + + return 0; +} + +static void __init rockchip_smp_prepare_cpus(unsigned int max_cpus) +{ + struct device_node *node; + unsigned int i; + + node = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-scu"); + if (!node) { + pr_err("%s: missing scu\n", __func__); + return; + } + + scu_base_addr = of_iomap(node, 0); + if (!scu_base_addr) { + pr_err("%s: could not map scu registers\n", __func__); + return; + } + + node = of_find_compatible_node(NULL, NULL, "rockchip,rk3066-smp-sram"); + if (!node) { + pr_err("%s: could not find sram dt node\n", __func__); + return; + } + + if (rockchip_smp_prepare_sram(node)) + return; + + node = of_find_compatible_node(NULL, NULL, "rockchip,rk3066-pmu"); + if (!node) { + pr_err("%s: could not find sram dt node\n", __func__); + return; + } + + pmu_base_addr = of_iomap(node, 0); + if (!pmu_base_addr) { + pr_err("%s: could not map pmu registers\n", __func__); + return; + } + + /* enable the SCU power domain */ + pmu_set_power_domain(PMU_PWRDN_SCU, true); + + /* + * While the number of cpus is gathered from dt, also get the number + * of cores from the scu to verify this value when booting the cores. + */ + ncores = scu_get_core_count(scu_base_addr); + + scu_enable(scu_base_addr); + + /* Make sure that all cores except the first are really off */ + for (i = 1; i < ncores; i++) + pmu_set_power_domain(0 + i, false); +} + +struct smp_operations rockchip_smp_ops __initdata = { + .smp_prepare_cpus = rockchip_smp_prepare_cpus, + .smp_boot_secondary = rockchip_boot_secondary, +}; |