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-rw-r--r--arch/arm/mach-rockchip/platsmp.c342
1 files changed, 342 insertions, 0 deletions
diff --git a/arch/arm/mach-rockchip/platsmp.c b/arch/arm/mach-rockchip/platsmp.c
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index 000000000..5b4ca3c3c
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+++ b/arch/arm/mach-rockchip/platsmp.c
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+/*
+ * 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 <linux/regmap.h>
+#include <linux/mfd/syscon.h>
+
+#include <linux/reset.h>
+#include <linux/cpu.h>
+#include <asm/cacheflush.h>
+#include <asm/cp15.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 struct regmap *pmu;
+
+static int pmu_power_domain_is_on(int pd)
+{
+ u32 val;
+ int ret;
+
+ ret = regmap_read(pmu, PMU_PWRDN_ST, &val);
+ if (ret < 0)
+ return ret;
+
+ return !(val & BIT(pd));
+}
+
+static struct reset_control *rockchip_get_core_reset(int cpu)
+{
+ struct device *dev = get_cpu_device(cpu);
+ struct device_node *np;
+
+ /* The cpu device is only available after the initial core bringup */
+ if (dev)
+ np = dev->of_node;
+ else
+ np = of_get_cpu_node(cpu, 0);
+
+ return of_reset_control_get(np, NULL);
+}
+
+static int pmu_set_power_domain(int pd, bool on)
+{
+ u32 val = (on) ? 0 : BIT(pd);
+ int ret;
+
+ /*
+ * We need to soft reset the cpu when we turn off the cpu power domain,
+ * or else the active processors might be stalled when the individual
+ * processor is powered down.
+ */
+ if (read_cpuid_part() != ARM_CPU_PART_CORTEX_A9) {
+ struct reset_control *rstc = rockchip_get_core_reset(pd);
+
+ if (IS_ERR(rstc)) {
+ pr_err("%s: could not get reset control for core %d\n",
+ __func__, pd);
+ return PTR_ERR(rstc);
+ }
+
+ if (on)
+ reset_control_deassert(rstc);
+ else
+ reset_control_assert(rstc);
+
+ reset_control_put(rstc);
+ }
+
+ ret = regmap_update_bits(pmu, PMU_PWRDN_CON, BIT(pd), val);
+ if (ret < 0) {
+ pr_err("%s: could not update power domain\n", __func__);
+ return ret;
+ }
+
+ ret = -1;
+ while (ret != on) {
+ ret = pmu_power_domain_is_on(pd);
+ if (ret < 0) {
+ pr_err("%s: could not read power domain state\n",
+ __func__);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * Handling of CPU cores
+ */
+
+static int __cpuinit rockchip_boot_secondary(unsigned int cpu,
+ struct task_struct *idle)
+{
+ int ret;
+
+ if (!sram_base_addr || !pmu) {
+ 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 */
+ ret = pmu_set_power_domain(0 + cpu, true);
+ if (ret < 0)
+ return ret;
+
+ if (read_cpuid_part() != ARM_CPU_PART_CORTEX_A9) {
+ /* We communicate with the bootrom to active the cpus other
+ * than cpu0, after a blob of initialize code, they will
+ * stay at wfe state, once they are actived, they will check
+ * the mailbox:
+ * sram_base_addr + 4: 0xdeadbeaf
+ * sram_base_addr + 8: start address for pc
+ * */
+ udelay(10);
+ writel(virt_to_phys(rockchip_secondary_startup),
+ sram_base_addr + 8);
+ writel(0xDEADBEAF, sram_base_addr + 4);
+ dsb_sev();
+ }
+
+ 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;
+ }
+
+ /* 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 const struct regmap_config rockchip_pmu_regmap_config = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+};
+
+static int __init rockchip_smp_prepare_pmu(void)
+{
+ struct device_node *node;
+ void __iomem *pmu_base;
+
+ /*
+ * This function is only called via smp_ops->smp_prepare_cpu().
+ * That only happens if a "/cpus" device tree node exists
+ * and has an "enable-method" property that selects the SMP
+ * operations defined herein.
+ */
+ node = of_find_node_by_path("/cpus");
+
+ pmu = syscon_regmap_lookup_by_phandle(node, "rockchip,pmu");
+ of_node_put(node);
+ if (!IS_ERR(pmu))
+ return 0;
+
+ pmu = syscon_regmap_lookup_by_compatible("rockchip,rk3066-pmu");
+ if (!IS_ERR(pmu))
+ return 0;
+
+ /* fallback, create our own regmap for the pmu area */
+ pmu = NULL;
+ node = of_find_compatible_node(NULL, NULL, "rockchip,rk3066-pmu");
+ if (!node) {
+ pr_err("%s: could not find pmu dt node\n", __func__);
+ return -ENODEV;
+ }
+
+ pmu_base = of_iomap(node, 0);
+ if (!pmu_base) {
+ pr_err("%s: could not map pmu registers\n", __func__);
+ return -ENOMEM;
+ }
+
+ pmu = regmap_init_mmio(NULL, pmu_base, &rockchip_pmu_regmap_config);
+ if (IS_ERR(pmu)) {
+ int ret = PTR_ERR(pmu);
+
+ iounmap(pmu_base);
+ pmu = NULL;
+ pr_err("%s: regmap init failed\n", __func__);
+ return ret;
+ }
+
+ 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, "rockchip,rk3066-smp-sram");
+ if (!node) {
+ pr_err("%s: could not find sram dt node\n", __func__);
+ return;
+ }
+
+ sram_base_addr = of_iomap(node, 0);
+ if (!sram_base_addr) {
+ pr_err("%s: could not map sram registers\n", __func__);
+ return;
+ }
+
+ if (rockchip_smp_prepare_pmu())
+ return;
+
+ if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9) {
+ if (rockchip_smp_prepare_sram(node))
+ return;
+
+ /* enable the SCU power domain */
+ pmu_set_power_domain(PMU_PWRDN_SCU, true);
+
+ 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;
+ }
+
+ /*
+ * 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);
+ pr_err("%s: ncores %d\n", __func__, ncores);
+
+ scu_enable(scu_base_addr);
+ } else {
+ unsigned int l2ctlr;
+
+ asm ("mrc p15, 1, %0, c9, c0, 2\n" : "=r" (l2ctlr));
+ ncores = ((l2ctlr >> 24) & 0x3) + 1;
+ }
+
+ /* Make sure that all cores except the first are really off */
+ for (i = 1; i < ncores; i++)
+ pmu_set_power_domain(0 + i, false);
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+static int rockchip_cpu_kill(unsigned int cpu)
+{
+ pmu_set_power_domain(0 + cpu, false);
+ return 1;
+}
+
+static void rockchip_cpu_die(unsigned int cpu)
+{
+ v7_exit_coherency_flush(louis);
+ while(1)
+ cpu_do_idle();
+}
+#endif
+
+static struct smp_operations rockchip_smp_ops __initdata = {
+ .smp_prepare_cpus = rockchip_smp_prepare_cpus,
+ .smp_boot_secondary = rockchip_boot_secondary,
+#ifdef CONFIG_HOTPLUG_CPU
+ .cpu_kill = rockchip_cpu_kill,
+ .cpu_die = rockchip_cpu_die,
+#endif
+};
+CPU_METHOD_OF_DECLARE(rk3066_smp, "rockchip,rk3066-smp", &rockchip_smp_ops);