diff options
Diffstat (limited to 'arch/arm/mach-imx/platsmp.c')
-rw-r--r-- | arch/arm/mach-imx/platsmp.c | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/arch/arm/mach-imx/platsmp.c b/arch/arm/mach-imx/platsmp.c new file mode 100644 index 000000000..cf4e93358 --- /dev/null +++ b/arch/arm/mach-imx/platsmp.c @@ -0,0 +1,124 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright 2011 Freescale Semiconductor, Inc. + * Copyright 2011 Linaro Ltd. + */ + +#include <linux/init.h> +#include <linux/of_address.h> +#include <linux/of.h> +#include <linux/smp.h> + +#include <asm/cacheflush.h> +#include <asm/page.h> +#include <asm/smp_scu.h> +#include <asm/mach/map.h> + +#include "common.h" +#include "hardware.h" + +u32 g_diag_reg; +static void __iomem *scu_base; + +static struct map_desc scu_io_desc __initdata = { + /* .virtual and .pfn are run-time assigned */ + .length = SZ_4K, + .type = MT_DEVICE, +}; + +void __init imx_scu_map_io(void) +{ + unsigned long base; + + /* Get SCU base */ + asm("mrc p15, 4, %0, c15, c0, 0" : "=r" (base)); + + scu_io_desc.virtual = IMX_IO_P2V(base); + scu_io_desc.pfn = __phys_to_pfn(base); + iotable_init(&scu_io_desc, 1); + + scu_base = IMX_IO_ADDRESS(base); +} + +static int imx_boot_secondary(unsigned int cpu, struct task_struct *idle) +{ + imx_set_cpu_jump(cpu, v7_secondary_startup); + imx_enable_cpu(cpu, true); + return 0; +} + +/* + * Initialise the CPU possible map early - this describes the CPUs + * which may be present or become present in the system. + */ +static void __init imx_smp_init_cpus(void) +{ + int i, ncores; + + ncores = scu_get_core_count(scu_base); + + for (i = ncores; i < NR_CPUS; i++) + set_cpu_possible(i, false); +} + +void imx_smp_prepare(void) +{ + scu_enable(scu_base); +} + +static void __init imx_smp_prepare_cpus(unsigned int max_cpus) +{ + imx_smp_prepare(); + + /* + * The diagnostic register holds the errata bits. Mostly bootloader + * does not bring up secondary cores, so that when errata bits are set + * in bootloader, they are set only for boot cpu. But on a SMP + * configuration, it should be equally done on every single core. + * Read the register from boot cpu here, and will replicate it into + * secondary cores when booting them. + */ + asm("mrc p15, 0, %0, c15, c0, 1" : "=r" (g_diag_reg) : : "cc"); + sync_cache_w(&g_diag_reg); +} + +const struct smp_operations imx_smp_ops __initconst = { + .smp_init_cpus = imx_smp_init_cpus, + .smp_prepare_cpus = imx_smp_prepare_cpus, + .smp_boot_secondary = imx_boot_secondary, +#ifdef CONFIG_HOTPLUG_CPU + .cpu_die = imx_cpu_die, + .cpu_kill = imx_cpu_kill, +#endif +}; + +#define DCFG_CCSR_SCRATCHRW1 0x200 + +static int ls1021a_boot_secondary(unsigned int cpu, struct task_struct *idle) +{ + arch_send_wakeup_ipi_mask(cpumask_of(cpu)); + + return 0; +} + +static void __init ls1021a_smp_prepare_cpus(unsigned int max_cpus) +{ + struct device_node *np; + void __iomem *dcfg_base; + unsigned long paddr; + + np = of_find_compatible_node(NULL, NULL, "fsl,ls1021a-dcfg"); + dcfg_base = of_iomap(np, 0); + of_node_put(np); + BUG_ON(!dcfg_base); + + paddr = __pa_symbol(secondary_startup); + writel_relaxed(cpu_to_be32(paddr), dcfg_base + DCFG_CCSR_SCRATCHRW1); + + iounmap(dcfg_base); +} + +const struct smp_operations ls1021a_smp_ops __initconst = { + .smp_prepare_cpus = ls1021a_smp_prepare_cpus, + .smp_boot_secondary = ls1021a_boot_secondary, +}; |