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author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-08-23 13:44:43 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-08-23 13:44:43 -0700 |
commit | 9e259f9352d52053058a234f7c062c4e4f56dc85 (patch) | |
tree | bfb1c442e27f95ddb9a04bae2a44ca9e3dd69a85 /drivers/soc/renesas/r9a06g032-smp.c | |
parent | 5563ae9b39c5ba492be1b18f2d72fd43ba549915 (diff) | |
parent | f0fc40aff6fee100ffbed8328a0df88f8aa75fce (diff) | |
download | op-kernel-dev-9e259f9352d52053058a234f7c062c4e4f56dc85.zip op-kernel-dev-9e259f9352d52053058a234f7c062c4e4f56dc85.tar.gz |
Merge tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM 32-bit SoC platform updates from Olof Johansson:
"Most of the SoC updates in this cycle are cleanups and moves to more
modern infrastructure:
- Davinci was moved to common clock framework
- OMAP1-based Amstrad E3 "Superphone" saw a bunch of cleanups to the
keyboard interface (bitbanged AT keyboard via GPIO).
- Removal of some stale code for Renesas platforms
- Power management improvements for i.MX6LL"
* tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (112 commits)
ARM: uniphier: select RESET_CONTROLLER
arm64: uniphier: select RESET_CONTROLLER
ARM: uniphier: remove empty Makefile
ARM: exynos: Clear global variable on init error path
ARM: exynos: Remove outdated maintainer information
ARM: shmobile: Always enable ARCH_TIMER on SoCs with A7 and/or A15
ARM: shmobile: r8a7779: hide unused r8a7779_platform_cpu_kill
soc: r9a06g032: don't build SMP files for non-SMP config
ARM: shmobile: Add the R9A06G032 SMP enabler driver
ARM: at91: pm: configure wakeup sources for ULP1 mode
ARM: at91: pm: add PMC fast startup registers defines
ARM: at91: pm: Add ULP1 mode support
ARM: at91: pm: Use ULP0 naming instead of slow clock
ARM: hisi: handle of_iomap and fix missing of_node_put
ARM: hisi: check of_iomap and fix missing of_node_put
ARM: hisi: fix error handling and missing of_node_put
ARM: mx5: Set the DBGEN bit in ARM_GPC register
ARM: imx51: Configure M4IF to avoid visual artifacts
ARM: imx: call imx6sx_cpuidle_init() conditionally for 6sll
ARM: imx: fix i.MX6SLL build
...
Diffstat (limited to 'drivers/soc/renesas/r9a06g032-smp.c')
-rw-r--r-- | drivers/soc/renesas/r9a06g032-smp.c | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/drivers/soc/renesas/r9a06g032-smp.c b/drivers/soc/renesas/r9a06g032-smp.c new file mode 100644 index 0000000..a1926e8 --- /dev/null +++ b/drivers/soc/renesas/r9a06g032-smp.c @@ -0,0 +1,96 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * R9A06G032 Second CA7 enabler. + * + * Copyright (C) 2018 Renesas Electronics Europe Limited + * + * Michel Pollet <michel.pollet@bp.renesas.com>, <buserror@gmail.com> + * Derived from actions,s500-smp + */ + +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/smp.h> + +/* + * The second CPU is parked in ROM at boot time. It requires waking it after + * writing an address into the BOOTADDR register of sysctrl. + * + * So the default value of the "cpu-release-addr" corresponds to BOOTADDR... + * + * *However* the BOOTADDR register is not available when the kernel + * starts in NONSEC mode. + * + * So for NONSEC mode, the bootloader re-parks the second CPU into a pen + * in SRAM, and changes the "cpu-release-addr" of linux's DT to a SRAM address, + * which is not restricted. + */ + +static void __iomem *cpu_bootaddr; + +static DEFINE_SPINLOCK(cpu_lock); + +static int +r9a06g032_smp_boot_secondary(unsigned int cpu, + struct task_struct *idle) +{ + if (!cpu_bootaddr) + return -ENODEV; + + spin_lock(&cpu_lock); + + writel(__pa_symbol(secondary_startup), cpu_bootaddr); + arch_send_wakeup_ipi_mask(cpumask_of(cpu)); + + spin_unlock(&cpu_lock); + + return 0; +} + +static void __init r9a06g032_smp_prepare_cpus(unsigned int max_cpus) +{ + struct device_node *dn; + int ret = -EINVAL, dns; + u32 bootaddr; + + dn = of_get_cpu_node(1, NULL); + if (!dn) { + pr_err("CPU#1: missing device tree node\n"); + return; + } + /* + * Determine the address from which the CPU is polling. + * The bootloader *does* change this property. + * Note: The property can be either 64 or 32 bits, so handle both cases + */ + if (of_find_property(dn, "cpu-release-addr", &dns)) { + if (dns == sizeof(u64)) { + u64 temp; + + ret = of_property_read_u64(dn, + "cpu-release-addr", &temp); + bootaddr = temp; + } else { + ret = of_property_read_u32(dn, + "cpu-release-addr", + &bootaddr); + } + } + of_node_put(dn); + if (ret) { + pr_err("CPU#1: invalid cpu-release-addr property\n"); + return; + } + pr_info("CPU#1: cpu-release-addr %08x\n", bootaddr); + + cpu_bootaddr = ioremap(bootaddr, sizeof(bootaddr)); +} + +static const struct smp_operations r9a06g032_smp_ops __initconst = { + .smp_prepare_cpus = r9a06g032_smp_prepare_cpus, + .smp_boot_secondary = r9a06g032_smp_boot_secondary, +}; + +CPU_METHOD_OF_DECLARE(r9a06g032_smp, + "renesas,r9a06g032-smp", &r9a06g032_smp_ops); |