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author | Martin Blumenstingl <martin.blumenstingl@googlemail.com> | 2017-09-17 18:45:21 +0200 |
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committer | Kevin Hilman <khilman@baylibre.com> | 2017-10-29 08:29:41 -0700 |
commit | d850f3e5d2966e5c9eb55f66181cee960737e04c (patch) | |
tree | dbdba02a9a4302d4a6b2b059ccd82ecd47c2a814 /arch/arm/mach-meson | |
parent | 936a4174435b376557ee2610eae03592baeb9016 (diff) | |
download | op-kernel-dev-d850f3e5d2966e5c9eb55f66181cee960737e04c.zip op-kernel-dev-d850f3e5d2966e5c9eb55f66181cee960737e04c.tar.gz |
ARM: meson: Add SMP bringup code for Meson8 and Meson8b
This adds the necessary SMP-operations and startup code to use the
additional cores on the Amlogic Meson8/Meson8m2 (both are using the same
sequence) and Meson8b (using a slightly difference sequence) SoCs.
Signed-off-by: Carlo Caione <carlo@endlessm.com>
[add Meson8/Meson8m2 support and allow taking CPU cores offline as well]
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Diffstat (limited to 'arch/arm/mach-meson')
-rw-r--r-- | arch/arm/mach-meson/Kconfig | 1 | ||||
-rw-r--r-- | arch/arm/mach-meson/Makefile | 1 | ||||
-rw-r--r-- | arch/arm/mach-meson/platsmp.c | 440 |
3 files changed, 442 insertions, 0 deletions
diff --git a/arch/arm/mach-meson/Kconfig b/arch/arm/mach-meson/Kconfig index ee30511..a0c6476 100644 --- a/arch/arm/mach-meson/Kconfig +++ b/arch/arm/mach-meson/Kconfig @@ -9,6 +9,7 @@ menuconfig ARCH_MESON select PINCTRL_MESON select COMMON_CLK select COMMON_CLK_AMLOGIC + select HAVE_ARM_SCU if SMP if ARCH_MESON diff --git a/arch/arm/mach-meson/Makefile b/arch/arm/mach-meson/Makefile index 9d7380e..bc26c85 100644 --- a/arch/arm/mach-meson/Makefile +++ b/arch/arm/mach-meson/Makefile @@ -1 +1,2 @@ obj-$(CONFIG_ARCH_MESON) += meson.o +obj-$(CONFIG_SMP) += platsmp.o diff --git a/arch/arm/mach-meson/platsmp.c b/arch/arm/mach-meson/platsmp.c new file mode 100644 index 0000000..2555f90 --- /dev/null +++ b/arch/arm/mach-meson/platsmp.c @@ -0,0 +1,440 @@ +/* + * Copyright (C) 2015 Carlo Caione <carlo@endlessm.com> + * Copyright (C) 2017 Martin Blumenstingl <martin.blumenstingl@googlemail.com> + * + * 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/io.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/regmap.h> +#include <linux/reset.h> +#include <linux/smp.h> +#include <linux/mfd/syscon.h> + +#include <asm/cacheflush.h> +#include <asm/cp15.h> +#include <asm/smp_scu.h> +#include <asm/smp_plat.h> + +#define MESON_SMP_SRAM_CPU_CTRL_REG (0x00) +#define MESON_SMP_SRAM_CPU_CTRL_ADDR_REG(c) (0x04 + ((c - 1) << 2)) + +#define MESON_CPU_AO_RTI_PWR_A9_CNTL0 (0x00) +#define MESON_CPU_AO_RTI_PWR_A9_CNTL1 (0x04) +#define MESON_CPU_AO_RTI_PWR_A9_MEM_PD0 (0x14) + +#define MESON_CPU_PWR_A9_CNTL0_M(c) (0x03 << ((c * 2) + 16)) +#define MESON_CPU_PWR_A9_CNTL1_M(c) (0x03 << ((c + 1) << 1)) +#define MESON_CPU_PWR_A9_MEM_PD0_M(c) (0x0f << (32 - (c * 4))) +#define MESON_CPU_PWR_A9_CNTL1_ST(c) (0x01 << (c + 16)) + +static void __iomem *sram_base; +static void __iomem *scu_base; +static struct regmap *pmu; + +static struct reset_control *meson_smp_get_core_reset(int cpu) +{ + struct device_node *np = of_get_cpu_node(cpu, 0); + + return of_reset_control_get_exclusive(np, NULL); +} + +static void meson_smp_set_cpu_ctrl(int cpu, bool on_off) +{ + u32 val = readl(sram_base + MESON_SMP_SRAM_CPU_CTRL_REG); + + if (on_off) + val |= BIT(cpu); + else + val &= ~BIT(cpu); + + /* keep bit 0 always enabled */ + val |= BIT(0); + + writel(val, sram_base + MESON_SMP_SRAM_CPU_CTRL_REG); +} + +static void __init meson_smp_prepare_cpus(const char *scu_compatible, + const char *pmu_compatible, + const char *sram_compatible) +{ + static struct device_node *node; + + /* SMP SRAM */ + node = of_find_compatible_node(NULL, NULL, sram_compatible); + if (!node) { + pr_err("Missing SRAM node\n"); + return; + } + + sram_base = of_iomap(node, 0); + if (!sram_base) { + pr_err("Couldn't map SRAM registers\n"); + return; + } + + /* PMU */ + pmu = syscon_regmap_lookup_by_compatible(pmu_compatible); + if (IS_ERR(pmu)) { + pr_err("Couldn't map PMU registers\n"); + return; + } + + /* SCU */ + node = of_find_compatible_node(NULL, NULL, scu_compatible); + if (!node) { + pr_err("Missing SCU node\n"); + return; + } + + scu_base = of_iomap(node, 0); + if (!scu_base) { + pr_err("Couln't map SCU registers\n"); + return; + } + + scu_enable(scu_base); +} + +static void __init meson8b_smp_prepare_cpus(unsigned int max_cpus) +{ + meson_smp_prepare_cpus("arm,cortex-a5-scu", "amlogic,meson8b-pmu", + "amlogic,meson8b-smp-sram"); +} + +static void __init meson8_smp_prepare_cpus(unsigned int max_cpus) +{ + meson_smp_prepare_cpus("arm,cortex-a9-scu", "amlogic,meson8-pmu", + "amlogic,meson8-smp-sram"); +} + +static void meson_smp_begin_secondary_boot(unsigned int cpu) +{ + /* + * Set the entry point before powering on the CPU through the SCU. This + * is needed if the CPU is in "warm" state (= after rebooting the + * system without power-cycling, or when taking the CPU offline and + * then taking it online again. + */ + writel(__pa_symbol(secondary_startup), + sram_base + MESON_SMP_SRAM_CPU_CTRL_ADDR_REG(cpu)); + + /* + * SCU Power on CPU (needs to be done before starting the CPU, + * otherwise the secondary CPU will not start). + */ + scu_cpu_power_enable(scu_base, cpu); +} + +static int meson_smp_finalize_secondary_boot(unsigned int cpu) +{ + unsigned long timeout; + + timeout = jiffies + (10 * HZ); + while (readl(sram_base + MESON_SMP_SRAM_CPU_CTRL_ADDR_REG(cpu))) { + if (!time_before(jiffies, timeout)) { + pr_err("Timeout while waiting for CPU%d status\n", + cpu); + return -ETIMEDOUT; + } + } + + writel(__pa_symbol(secondary_startup), + sram_base + MESON_SMP_SRAM_CPU_CTRL_ADDR_REG(cpu)); + + meson_smp_set_cpu_ctrl(cpu, true); + + return 0; +} + +static int meson8_smp_boot_secondary(unsigned int cpu, + struct task_struct *idle) +{ + struct reset_control *rstc; + int ret; + + rstc = meson_smp_get_core_reset(cpu); + if (IS_ERR(rstc)) { + pr_err("Couldn't get the reset controller for CPU%d\n", cpu); + return PTR_ERR(rstc); + } + + meson_smp_begin_secondary_boot(cpu); + + /* Reset enable */ + ret = reset_control_assert(rstc); + if (ret) { + pr_err("Failed to assert CPU%d reset\n", cpu); + goto out; + } + + /* CPU power ON */ + ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL1, + MESON_CPU_PWR_A9_CNTL1_M(cpu), 0); + if (ret < 0) { + pr_err("Couldn't wake up CPU%d\n", cpu); + goto out; + } + + udelay(10); + + /* Isolation disable */ + ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL0, BIT(cpu), + 0); + if (ret < 0) { + pr_err("Error when disabling isolation of CPU%d\n", cpu); + goto out; + } + + /* Reset disable */ + ret = reset_control_deassert(rstc); + if (ret) { + pr_err("Failed to de-assert CPU%d reset\n", cpu); + goto out; + } + + ret = meson_smp_finalize_secondary_boot(cpu); + if (ret) + goto out; + +out: + reset_control_put(rstc); + + return 0; +} + +static int meson8b_smp_boot_secondary(unsigned int cpu, + struct task_struct *idle) +{ + struct reset_control *rstc; + int ret; + u32 val; + + rstc = meson_smp_get_core_reset(cpu); + if (IS_ERR(rstc)) { + pr_err("Couldn't get the reset controller for CPU%d\n", cpu); + return PTR_ERR(rstc); + } + + meson_smp_begin_secondary_boot(cpu); + + /* CPU power UP */ + ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL0, + MESON_CPU_PWR_A9_CNTL0_M(cpu), 0); + if (ret < 0) { + pr_err("Couldn't power up CPU%d\n", cpu); + goto out; + } + + udelay(5); + + /* Reset enable */ + ret = reset_control_assert(rstc); + if (ret) { + pr_err("Failed to assert CPU%d reset\n", cpu); + goto out; + } + + /* Memory power UP */ + ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_MEM_PD0, + MESON_CPU_PWR_A9_MEM_PD0_M(cpu), 0); + if (ret < 0) { + pr_err("Couldn't power up the memory for CPU%d\n", cpu); + goto out; + } + + /* Wake up CPU */ + ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL1, + MESON_CPU_PWR_A9_CNTL1_M(cpu), 0); + if (ret < 0) { + pr_err("Couldn't wake up CPU%d\n", cpu); + goto out; + } + + udelay(10); + + ret = regmap_read_poll_timeout(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL1, val, + val & MESON_CPU_PWR_A9_CNTL1_ST(cpu), + 10, 10000); + if (ret) { + pr_err("Timeout while polling PMU for CPU%d status\n", cpu); + goto out; + } + + /* Isolation disable */ + ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL0, BIT(cpu), + 0); + if (ret < 0) { + pr_err("Error when disabling isolation of CPU%d\n", cpu); + goto out; + } + + /* Reset disable */ + ret = reset_control_deassert(rstc); + if (ret) { + pr_err("Failed to de-assert CPU%d reset\n", cpu); + goto out; + } + + ret = meson_smp_finalize_secondary_boot(cpu); + if (ret) + goto out; + +out: + reset_control_put(rstc); + + return 0; +} + +#ifdef CONFIG_HOTPLUG_CPU +static void meson8_smp_cpu_die(unsigned int cpu) +{ + meson_smp_set_cpu_ctrl(cpu, false); + + v7_exit_coherency_flush(louis); + + scu_power_mode(scu_base, SCU_PM_POWEROFF); + + dsb(); + wfi(); + + /* we should never get here */ + WARN_ON(1); +} + +static int meson8_smp_cpu_kill(unsigned int cpu) +{ + int ret, power_mode; + unsigned long timeout; + + timeout = jiffies + (50 * HZ); + do { + power_mode = scu_get_cpu_power_mode(scu_base, cpu); + + if (power_mode == SCU_PM_POWEROFF) + break; + + usleep_range(10000, 15000); + } while (time_before(jiffies, timeout)); + + if (power_mode != SCU_PM_POWEROFF) { + pr_err("Error while waiting for SCU power-off on CPU%d\n", + cpu); + return -ETIMEDOUT; + } + + msleep(30); + + /* Isolation enable */ + ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL0, BIT(cpu), + 0x3); + if (ret < 0) { + pr_err("Error when enabling isolation for CPU%d\n", cpu); + return ret; + } + + udelay(10); + + /* CPU power OFF */ + ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL1, + MESON_CPU_PWR_A9_CNTL1_M(cpu), 0x3); + if (ret < 0) { + pr_err("Couldn't change sleep status of CPU%d\n", cpu); + return ret; + } + + return 1; +} + +static int meson8b_smp_cpu_kill(unsigned int cpu) +{ + int ret, power_mode, count = 5000; + + do { + power_mode = scu_get_cpu_power_mode(scu_base, cpu); + + if (power_mode == SCU_PM_POWEROFF) + break; + + udelay(10); + } while (++count); + + if (power_mode != SCU_PM_POWEROFF) { + pr_err("Error while waiting for SCU power-off on CPU%d\n", + cpu); + return -ETIMEDOUT; + } + + udelay(10); + + /* CPU power DOWN */ + ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL0, + MESON_CPU_PWR_A9_CNTL0_M(cpu), 0x3); + if (ret < 0) { + pr_err("Couldn't power down CPU%d\n", cpu); + return ret; + } + + /* Isolation enable */ + ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL0, BIT(cpu), + 0x3); + if (ret < 0) { + pr_err("Error when enabling isolation for CPU%d\n", cpu); + return ret; + } + + udelay(10); + + /* Sleep status */ + ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL1, + MESON_CPU_PWR_A9_CNTL1_M(cpu), 0x3); + if (ret < 0) { + pr_err("Couldn't change sleep status of CPU%d\n", cpu); + return ret; + } + + /* Memory power DOWN */ + ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_MEM_PD0, + MESON_CPU_PWR_A9_MEM_PD0_M(cpu), 0xf); + if (ret < 0) { + pr_err("Couldn't power down the memory of CPU%d\n", cpu); + return ret; + } + + return 1; +} +#endif + +static struct smp_operations meson8_smp_ops __initdata = { + .smp_prepare_cpus = meson8_smp_prepare_cpus, + .smp_boot_secondary = meson8_smp_boot_secondary, +#ifdef CONFIG_HOTPLUG_CPU + .cpu_die = meson8_smp_cpu_die, + .cpu_kill = meson8_smp_cpu_kill, +#endif +}; + +static struct smp_operations meson8b_smp_ops __initdata = { + .smp_prepare_cpus = meson8b_smp_prepare_cpus, + .smp_boot_secondary = meson8b_smp_boot_secondary, +#ifdef CONFIG_HOTPLUG_CPU + .cpu_die = meson8_smp_cpu_die, + .cpu_kill = meson8b_smp_cpu_kill, +#endif +}; + +CPU_METHOD_OF_DECLARE(meson8_smp, "amlogic,meson8-smp", &meson8_smp_ops); +CPU_METHOD_OF_DECLARE(meson8b_smp, "amlogic,meson8b-smp", &meson8b_smp_ops); |