From 7416d4411361c79e10667c571b15eed18e811f44 Mon Sep 17 00:00:00 2001 From: Michel Pollet Date: Thu, 28 Jun 2018 09:17:13 +0100 Subject: ARM: shmobile: Add the R9A06G032 SMP enabler driver The Renesas R9A06G032 second CA7 is parked in a ROM pen at boot time, it equires a special enable method to get it started. Signed-off-by: Michel Pollet Reviewed-by: Geert Uytterhoeven Signed-off-by: Simon Horman --- drivers/soc/renesas/Makefile | 1 + drivers/soc/renesas/r9a06g032-smp.c | 96 +++++++++++++++++++++++++++++++++++++ 2 files changed, 97 insertions(+) create mode 100644 drivers/soc/renesas/r9a06g032-smp.c (limited to 'drivers/soc/renesas') diff --git a/drivers/soc/renesas/Makefile b/drivers/soc/renesas/Makefile index 7dc0f20d7907..44a0d6b10192 100644 --- a/drivers/soc/renesas/Makefile +++ b/drivers/soc/renesas/Makefile @@ -18,6 +18,7 @@ obj-$(CONFIG_SYSC_R8A77970) += r8a77970-sysc.o obj-$(CONFIG_SYSC_R8A77980) += r8a77980-sysc.o obj-$(CONFIG_SYSC_R8A77990) += r8a77990-sysc.o obj-$(CONFIG_SYSC_R8A77995) += r8a77995-sysc.o +obj-$(CONFIG_ARCH_R9A06G032) += r9a06g032-smp.o # Family obj-$(CONFIG_RST_RCAR) += rcar-rst.o diff --git a/drivers/soc/renesas/r9a06g032-smp.c b/drivers/soc/renesas/r9a06g032-smp.c new file mode 100644 index 000000000000..a1926e8d73f2 --- /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 , + * Derived from actions,s500-smp + */ + +#include +#include +#include +#include + +/* + * 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); -- cgit v1.2.3 From c83e9c4873d34aa8d9bbb90345fee0757b6233ef Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Fri, 6 Jul 2018 17:16:01 +0200 Subject: soc: r9a06g032: don't build SMP files for non-SMP config Without CONFIG_SMP, we get a build failure: In file included from include/linux/byteorder/little_endian.h:5, from arch/arm/include/uapi/asm/byteorder.h:22, from include/asm-generic/bitops/le.h:6, from arch/arm/include/asm/bitops.h:342, from include/linux/bitops.h:18, from include/linux/kernel.h:11, from include/asm-generic/bug.h:18, from arch/arm/include/asm/bug.h:60, from include/linux/bug.h:5, from include/linux/io.h:23, from drivers/soc/renesas/r9a06g032-smp.c:11: drivers/soc/renesas/r9a06g032-smp.c: In function 'r9a06g032_smp_boot_secondary': drivers/soc/renesas/r9a06g032-smp.c:43:21: error: 'secondary_startup' undeclared (first use in this function) writel(__pa_symbol(secondary_startup), cpu_bootaddr); ^~~~~~~~~~~~~~~~~ This makes the compilation of that file conditional on SMP support. It would probably be better for consistency to leave that file in arch/arm/mach-shmobile/, matching what we do for all other smp operations. Fixes: cde4f86f9249 ("arm: shmobile: Add the R9A06G032 SMP enabler driver") Signed-off-by: Arnd Bergmann Reviewed-by: Geert Uytterhoeven Signed-off-by: Simon Horman --- drivers/soc/renesas/Makefile | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/soc/renesas') diff --git a/drivers/soc/renesas/Makefile b/drivers/soc/renesas/Makefile index 44a0d6b10192..c37b0803c1b6 100644 --- a/drivers/soc/renesas/Makefile +++ b/drivers/soc/renesas/Makefile @@ -18,7 +18,9 @@ obj-$(CONFIG_SYSC_R8A77970) += r8a77970-sysc.o obj-$(CONFIG_SYSC_R8A77980) += r8a77980-sysc.o obj-$(CONFIG_SYSC_R8A77990) += r8a77990-sysc.o obj-$(CONFIG_SYSC_R8A77995) += r8a77995-sysc.o +ifdef CONFIG_SMP obj-$(CONFIG_ARCH_R9A06G032) += r9a06g032-smp.o +endif # Family obj-$(CONFIG_RST_RCAR) += rcar-rst.o -- cgit v1.2.3