summaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-rockchip/platsmp.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/mach-rockchip/platsmp.c')
-rw-r--r--arch/arm/mach-rockchip/platsmp.c184
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,
+};