| Antoine Ténart | 7b7dfdd | 2014-06-04 18:03:42 +0200 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2014 Marvell Technology Group Ltd. |
| 3 | * |
| 4 | * Antoine Ténart <antoine.tenart@free-electrons.com> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 as |
| 8 | * published by the Free Software Foundation. |
| 9 | */ |
| 10 | |
| 11 | #include <linux/io.h> |
| 12 | #include <linux/delay.h> |
| 13 | #include <linux/of.h> |
| 14 | #include <linux/of_address.h> |
| 15 | |
| 16 | #include <asm/cacheflush.h> |
| 17 | #include <asm/smp_plat.h> |
| 18 | #include <asm/smp_scu.h> |
| 19 | |
| 20 | #define CPU_RESET 0x00 |
| 21 | |
| 22 | #define RESET_VECT 0x00 |
| 23 | #define SW_RESET_ADDR 0x94 |
| 24 | |
| 25 | extern void berlin_secondary_startup(void); |
| 26 | extern u32 boot_inst; |
| 27 | |
| 28 | static void __iomem *cpu_ctrl; |
| 29 | |
| 30 | static inline void berlin_perform_reset_cpu(unsigned int cpu) |
| 31 | { |
| 32 | u32 val; |
| 33 | |
| 34 | val = readl(cpu_ctrl + CPU_RESET); |
| 35 | val |= BIT(cpu_logical_map(cpu)); |
| 36 | writel(val, cpu_ctrl + CPU_RESET); |
| 37 | } |
| 38 | |
| 39 | static int berlin_boot_secondary(unsigned int cpu, struct task_struct *idle) |
| 40 | { |
| 41 | if (!cpu_ctrl) |
| 42 | return -EFAULT; |
| 43 | |
| 44 | /* |
| 45 | * Reset the CPU, making it to execute the instruction in the reset |
| 46 | * exception vector. |
| 47 | */ |
| 48 | berlin_perform_reset_cpu(cpu); |
| 49 | |
| 50 | return 0; |
| 51 | } |
| 52 | |
| 53 | static void __init berlin_smp_prepare_cpus(unsigned int max_cpus) |
| 54 | { |
| 55 | struct device_node *np; |
| 56 | void __iomem *scu_base; |
| 57 | void __iomem *vectors_base; |
| 58 | |
| 59 | np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-scu"); |
| 60 | scu_base = of_iomap(np, 0); |
| 61 | of_node_put(np); |
| 62 | if (!scu_base) |
| 63 | return; |
| 64 | |
| 65 | np = of_find_compatible_node(NULL, NULL, "marvell,berlin-cpu-ctrl"); |
| 66 | cpu_ctrl = of_iomap(np, 0); |
| 67 | of_node_put(np); |
| 68 | if (!cpu_ctrl) |
| 69 | goto unmap_scu; |
| 70 | |
| 71 | vectors_base = ioremap(CONFIG_VECTORS_BASE, SZ_32K); |
| 72 | if (!vectors_base) |
| 73 | goto unmap_scu; |
| 74 | |
| 75 | scu_enable(scu_base); |
| 76 | flush_cache_all(); |
| 77 | |
| 78 | /* |
| 79 | * Write the first instruction the CPU will execute after being reset |
| 80 | * in the reset exception vector. |
| 81 | */ |
| 82 | writel(boot_inst, vectors_base + RESET_VECT); |
| 83 | |
| 84 | /* |
| 85 | * Write the secondary startup address into the SW reset address |
| 86 | * vector. This is used by boot_inst. |
| 87 | */ |
| 88 | writel(virt_to_phys(berlin_secondary_startup), vectors_base + SW_RESET_ADDR); |
| 89 | |
| 90 | iounmap(vectors_base); |
| 91 | unmap_scu: |
| 92 | iounmap(scu_base); |
| 93 | } |
| 94 | |
| 95 | static struct smp_operations berlin_smp_ops __initdata = { |
| 96 | .smp_prepare_cpus = berlin_smp_prepare_cpus, |
| 97 | .smp_boot_secondary = berlin_boot_secondary, |
| 98 | }; |
| 99 | CPU_METHOD_OF_DECLARE(berlin_smp, "marvell,berlin-smp", &berlin_smp_ops); |