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Diffstat (limited to 'arch/arm/mach-actions/platsmp.c')
-rw-r--r-- | arch/arm/mach-actions/platsmp.c | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/arch/arm/mach-actions/platsmp.c b/arch/arm/mach-actions/platsmp.c new file mode 100644 index 000000000..f26618b43 --- /dev/null +++ b/arch/arm/mach-actions/platsmp.c @@ -0,0 +1,152 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Actions Semi Leopard + * + * This file is based on arm realview smp platform. + * + * Copyright 2012 Actions Semi Inc. + * Author: Actions Semi, Inc. + * + * Copyright (c) 2017 Andreas Färber + */ + +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/smp.h> +#include <linux/soc/actions/owl-sps.h> +#include <asm/cacheflush.h> +#include <asm/smp_plat.h> +#include <asm/smp_scu.h> + +#define OWL_CPU1_ADDR 0x50 +#define OWL_CPU1_FLAG 0x5c + +#define OWL_CPUx_FLAG_BOOT 0x55aa + +#define OWL_SPS_PG_CTL_PWR_CPU2 BIT(5) +#define OWL_SPS_PG_CTL_PWR_CPU3 BIT(6) +#define OWL_SPS_PG_CTL_ACK_CPU2 BIT(21) +#define OWL_SPS_PG_CTL_ACK_CPU3 BIT(22) + +static void __iomem *scu_base_addr; +static void __iomem *sps_base_addr; +static void __iomem *timer_base_addr; +static int ncores; + +static int s500_wakeup_secondary(unsigned int cpu) +{ + int ret; + + if (cpu > 3) + return -EINVAL; + + /* The generic PM domain driver is not available this early. */ + switch (cpu) { + case 2: + ret = owl_sps_set_pg(sps_base_addr, + OWL_SPS_PG_CTL_PWR_CPU2, + OWL_SPS_PG_CTL_ACK_CPU2, true); + if (ret) + return ret; + break; + case 3: + ret = owl_sps_set_pg(sps_base_addr, + OWL_SPS_PG_CTL_PWR_CPU3, + OWL_SPS_PG_CTL_ACK_CPU3, true); + if (ret) + return ret; + break; + } + + /* wait for CPUx to run to WFE instruction */ + udelay(200); + + writel(__pa_symbol(secondary_startup), + timer_base_addr + OWL_CPU1_ADDR + (cpu - 1) * 4); + writel(OWL_CPUx_FLAG_BOOT, + timer_base_addr + OWL_CPU1_FLAG + (cpu - 1) * 4); + + dsb_sev(); + mb(); + + return 0; +} + +static int s500_smp_boot_secondary(unsigned int cpu, struct task_struct *idle) +{ + int ret; + + ret = s500_wakeup_secondary(cpu); + if (ret) + return ret; + + udelay(10); + + smp_send_reschedule(cpu); + + writel(0, timer_base_addr + OWL_CPU1_ADDR + (cpu - 1) * 4); + writel(0, timer_base_addr + OWL_CPU1_FLAG + (cpu - 1) * 4); + + return 0; +} + +static void __init s500_smp_prepare_cpus(unsigned int max_cpus) +{ + struct device_node *node; + + node = of_find_compatible_node(NULL, NULL, "actions,s500-timer"); + if (!node) { + pr_err("%s: missing timer\n", __func__); + return; + } + + timer_base_addr = of_iomap(node, 0); + if (!timer_base_addr) { + pr_err("%s: could not map timer registers\n", __func__); + return; + } + + node = of_find_compatible_node(NULL, NULL, "actions,s500-sps"); + if (!node) { + pr_err("%s: missing sps\n", __func__); + return; + } + + sps_base_addr = of_iomap(node, 0); + if (!sps_base_addr) { + pr_err("%s: could not map sps registers\n", __func__); + return; + } + + if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9) { + 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_debug("%s: ncores %d\n", __func__, ncores); + + scu_enable(scu_base_addr); + } +} + +static const struct smp_operations s500_smp_ops __initconst = { + .smp_prepare_cpus = s500_smp_prepare_cpus, + .smp_boot_secondary = s500_smp_boot_secondary, +}; +CPU_METHOD_OF_DECLARE(s500_smp, "actions,s500-smp", &s500_smp_ops); |