From 3f20fb1153b374737acd40d42cb3cab2ae5dae35 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Mon, 14 Apr 2014 15:50:28 +0200 Subject: [PATCH 1/5] ARM: mvebu: introduce CPU reset code The Armada 370 and Armada XP have registers that allow to reset the CPUs, which is particularly useful to take the secondary CPUs out of reset in the context of the SMP support. Unfortunately, an implementation mistake was originally made and the support for these registers was integrated into the PMSU driver, which is in fact completely unrelated. And it turns out that the Armada 375 has the same CPU reset registers, but does not have the PMSU registers. Therefore, this commit creates a small CPU reset driver. All it does is provide a simple mvebu_cpu_reset_deassert() function that the SMP support code can call to take secondary CPUs out of reset. As of this commit, the driver isn't being used, it will be used through changes in the following commits. Note that we initially planned to use the 'reset controller' framework, but it requires the addition of "resets" properties in the Device Tree, which are causing too many problems if we want to keep the Device Tree backward compatibility. Moreover, the 'reset controller' framework is mainly useful when a device driver needs to request a reset of its device from a separate reset controller. In our case, the CPU reset handling and the SMP core code are both located in arch/arm/mach-mvebu/ and are tightly linked together, so there's no real benefit in going through a separate framework. Signed-off-by: Thomas Petazzoni Link: https://lkml.kernel.org/r/1397483433-25836-2-git-send-email-thomas.petazzoni@free-electrons.com Signed-off-by: Jason Cooper --- .../bindings/arm/armada-cpu-reset.txt | 14 ++++ arch/arm/mach-mvebu/Makefile | 2 +- arch/arm/mach-mvebu/common.h | 1 + arch/arm/mach-mvebu/cpu-reset.c | 82 +++++++++++++++++++ 4 files changed, 98 insertions(+), 1 deletion(-) create mode 100644 Documentation/devicetree/bindings/arm/armada-cpu-reset.txt create mode 100644 arch/arm/mach-mvebu/cpu-reset.c diff --git a/Documentation/devicetree/bindings/arm/armada-cpu-reset.txt b/Documentation/devicetree/bindings/arm/armada-cpu-reset.txt new file mode 100644 index 000000000000..b63a7b6ab998 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/armada-cpu-reset.txt @@ -0,0 +1,14 @@ +Marvell Armada CPU reset controller +=================================== + +Required properties: + +- compatible: Should be "marvell,armada-370-cpu-reset". + +- reg: should be register base and length as documented in the + datasheet for the CPU reset registers + +cpurst: cpurst@20800 { + compatible = "marvell,armada-370-cpu-reset"; + reg = <0x20800 0x20>; +}; diff --git a/arch/arm/mach-mvebu/Makefile b/arch/arm/mach-mvebu/Makefile index a63e43b6b451..f9cfab05c5f9 100644 --- a/arch/arm/mach-mvebu/Makefile +++ b/arch/arm/mach-mvebu/Makefile @@ -3,7 +3,7 @@ ccflags-$(CONFIG_ARCH_MULTIPLATFORM) := -I$(srctree)/$(src)/include \ AFLAGS_coherency_ll.o := -Wa,-march=armv7-a -obj-y += system-controller.o mvebu-soc-id.o +obj-y += system-controller.o mvebu-soc-id.o cpu-reset.o obj-$(CONFIG_MACH_MVEBU_V7) += board-v7.o obj-$(CONFIG_MACH_DOVE) += dove.o obj-$(CONFIG_ARCH_MVEBU) += coherency.o coherency_ll.o pmsu.o diff --git a/arch/arm/mach-mvebu/common.h b/arch/arm/mach-mvebu/common.h index 55449c487c9e..cfb129b144c0 100644 --- a/arch/arm/mach-mvebu/common.h +++ b/arch/arm/mach-mvebu/common.h @@ -18,6 +18,7 @@ #include void mvebu_restart(enum reboot_mode mode, const char *cmd); +int mvebu_cpu_reset_deassert(int cpu); void armada_xp_cpu_die(unsigned int cpu); diff --git a/arch/arm/mach-mvebu/cpu-reset.c b/arch/arm/mach-mvebu/cpu-reset.c new file mode 100644 index 000000000000..4ff4ce77f8b6 --- /dev/null +++ b/arch/arm/mach-mvebu/cpu-reset.c @@ -0,0 +1,82 @@ +/* + * Copyright (C) 2014 Marvell + * + * Thomas Petazzoni + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#define pr_fmt(fmt) "mvebu-cpureset: " fmt + +#include +#include +#include +#include +#include +#include "armada-370-xp.h" + +static void __iomem *cpu_reset_base; +static size_t cpu_reset_size; + +#define CPU_RESET_OFFSET(cpu) (cpu * 0x8) +#define CPU_RESET_ASSERT BIT(0) + +int mvebu_cpu_reset_deassert(int cpu) +{ + u32 reg; + + if (!cpu_reset_base) + return -ENODEV; + + if (CPU_RESET_OFFSET(cpu) >= cpu_reset_size) + return -EINVAL; + + reg = readl(cpu_reset_base + CPU_RESET_OFFSET(cpu)); + reg &= ~CPU_RESET_ASSERT; + writel(reg, cpu_reset_base + CPU_RESET_OFFSET(cpu)); + + return 0; +} + +static int __init mvebu_cpu_reset_init(void) +{ + struct device_node *np; + struct resource res; + int ret = 0; + + np = of_find_compatible_node(NULL, NULL, + "marvell,armada-370-cpu-reset"); + if (!np) + return 0; + + if (of_address_to_resource(np, 0, &res)) { + pr_err("unable to get resource\n"); + ret = -ENOENT; + goto out; + } + + if (!request_mem_region(res.start, resource_size(&res), + np->full_name)) { + pr_err("unable to request region\n"); + ret = -EBUSY; + goto out; + } + + cpu_reset_base = ioremap(res.start, resource_size(&res)); + if (!cpu_reset_base) { + pr_err("unable to map registers\n"); + release_mem_region(res.start, resource_size(&res)); + ret = -ENOMEM; + goto out; + } + + cpu_reset_size = resource_size(&res); + +out: + of_node_put(np); + return ret; +} + +early_initcall(mvebu_cpu_reset_init); From 49754ffef5dca1d212e5fea5957a2a164585e92c Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Mon, 14 Apr 2014 15:50:29 +0200 Subject: [PATCH 2/5] ARM: mvebu: start using the CPU reset driver This commit changes the PMSU driver to no longer map itself the CPU reset registers, and instead call into the CPU reset driver to deassert the secondary CPUs for SMP booting. In order to provide Device Tree backward compatibility, the CPU reset driver is extended to not only support its official compatible string "marvell,armada-370-cpu-reset", but to also look at the PMSU compatible string "marvell,armada-370-xp-pmsu" to find the CPU reset registers address. This allows old Device Tree to work correctly with newer kernel versions. Therefore, the CPU reset driver implements the following logic: * If one of the normal compatible strings "marvell,armada-370-cpu-reset" is found, then we map its first memory resource as the CPU reset registers. * Otherwise, if none of the normal compatible strings have been found, we look for the "marvell,armada-370-xp-pmsu" compatible string, and we map the second memory as the CPU reset registers. Signed-off-by: Thomas Petazzoni Link: https://lkml.kernel.org/r/1397483433-25836-3-git-send-email-thomas.petazzoni@free-electrons.com Acked-by: Gregory CLEMENT Signed-off-by: Jason Cooper --- arch/arm/mach-mvebu/cpu-reset.c | 53 +++++++++++++++++++++++---------- arch/arm/mach-mvebu/pmsu.c | 20 ++++++------- 2 files changed, 47 insertions(+), 26 deletions(-) diff --git a/arch/arm/mach-mvebu/cpu-reset.c b/arch/arm/mach-mvebu/cpu-reset.c index 4ff4ce77f8b6..4a8f9eebebea 100644 --- a/arch/arm/mach-mvebu/cpu-reset.c +++ b/arch/arm/mach-mvebu/cpu-reset.c @@ -40,42 +40,63 @@ int mvebu_cpu_reset_deassert(int cpu) return 0; } -static int __init mvebu_cpu_reset_init(void) +static int mvebu_cpu_reset_map(struct device_node *np, int res_idx) { - struct device_node *np; struct resource res; - int ret = 0; - np = of_find_compatible_node(NULL, NULL, - "marvell,armada-370-cpu-reset"); - if (!np) - return 0; - - if (of_address_to_resource(np, 0, &res)) { + if (of_address_to_resource(np, res_idx, &res)) { pr_err("unable to get resource\n"); - ret = -ENOENT; - goto out; + return -ENOENT; } if (!request_mem_region(res.start, resource_size(&res), np->full_name)) { pr_err("unable to request region\n"); - ret = -EBUSY; - goto out; + return -EBUSY; } cpu_reset_base = ioremap(res.start, resource_size(&res)); if (!cpu_reset_base) { pr_err("unable to map registers\n"); release_mem_region(res.start, resource_size(&res)); - ret = -ENOMEM; - goto out; + return -ENOMEM; } cpu_reset_size = resource_size(&res); -out: + return 0; +} + +int __init mvebu_cpu_reset_init(void) +{ + struct device_node *np; + int res_idx; + int ret; + + np = of_find_compatible_node(NULL, NULL, + "marvell,armada-370-cpu-reset"); + if (np) { + res_idx = 0; + } else { + /* + * This code is kept for backward compatibility with + * old Device Trees. + */ + np = of_find_compatible_node(NULL, NULL, + "marvell,armada-370-xp-pmsu"); + if (np) { + pr_warn(FW_WARN "deprecated pmsu binding\n"); + res_idx = 1; + } + } + + /* No reset node found */ + if (!np) + return -ENODEV; + + ret = mvebu_cpu_reset_map(np, res_idx); of_node_put(np); + return ret; } diff --git a/arch/arm/mach-mvebu/pmsu.c b/arch/arm/mach-mvebu/pmsu.c index d71ef53107c4..1807639173b1 100644 --- a/arch/arm/mach-mvebu/pmsu.c +++ b/arch/arm/mach-mvebu/pmsu.c @@ -21,14 +21,14 @@ #include #include #include +#include #include +#include "common.h" #include "pmsu.h" static void __iomem *pmsu_mp_base; -static void __iomem *pmsu_reset_base; #define PMSU_BOOT_ADDR_REDIRECT_OFFSET(cpu) ((cpu * 0x100) + 0x24) -#define PMSU_RESET_CTL_OFFSET(cpu) (cpu * 0x8) static struct of_device_id of_pmsu_table[] = { {.compatible = "marvell,armada-370-xp-pmsu"}, @@ -38,11 +38,11 @@ static struct of_device_id of_pmsu_table[] = { #ifdef CONFIG_SMP int armada_xp_boot_cpu(unsigned int cpu_id, void *boot_addr) { - int reg, hw_cpu; + int hw_cpu, ret; - if (!pmsu_mp_base || !pmsu_reset_base) { + if (!pmsu_mp_base) { pr_warn("Can't boot CPU. PMSU is uninitialized\n"); - return 1; + return -ENODEV; } hw_cpu = cpu_logical_map(cpu_id); @@ -50,10 +50,11 @@ int armada_xp_boot_cpu(unsigned int cpu_id, void *boot_addr) writel(virt_to_phys(boot_addr), pmsu_mp_base + PMSU_BOOT_ADDR_REDIRECT_OFFSET(hw_cpu)); - /* Release CPU from reset by clearing reset bit*/ - reg = readl(pmsu_reset_base + PMSU_RESET_CTL_OFFSET(hw_cpu)); - reg &= (~0x1); - writel(reg, pmsu_reset_base + PMSU_RESET_CTL_OFFSET(hw_cpu)); + ret = mvebu_cpu_reset_deassert(hw_cpu); + if (ret) { + pr_warn("unable to boot CPU: %d\n", ret); + return ret; + } return 0; } @@ -67,7 +68,6 @@ static int __init armada_370_xp_pmsu_init(void) if (np) { pr_info("Initializing Power Management Service Unit\n"); pmsu_mp_base = of_iomap(np, 0); - pmsu_reset_base = of_iomap(np, 1); of_node_put(np); } From bd045a1ebb48e5901508574188404d9bd3bdd72f Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Mon, 14 Apr 2014 15:50:30 +0200 Subject: [PATCH 3/5] ARM: mvebu: improve PMSU driver to request its resource Until now, the PMSU driver was using of_iomap() to map its registers, but of_iomap() doesn't call request_mem_region(). This commit fixes the memory mapping code of the PMSU to do so, which will also be useful for a later commit since we will need to adjust the resource base address and size for Device Tree backward compatibility. Signed-off-by: Thomas Petazzoni Link: https://lkml.kernel.org/r/1397483433-25836-4-git-send-email-thomas.petazzoni@free-electrons.com Acked-by: Gregory CLEMENT Signed-off-by: Jason Cooper --- arch/arm/mach-mvebu/pmsu.c | 36 +++++++++++++++++++++++++++++++----- 1 file changed, 31 insertions(+), 5 deletions(-) diff --git a/arch/arm/mach-mvebu/pmsu.c b/arch/arm/mach-mvebu/pmsu.c index 1807639173b1..b337fe56bae5 100644 --- a/arch/arm/mach-mvebu/pmsu.c +++ b/arch/arm/mach-mvebu/pmsu.c @@ -16,6 +16,8 @@ * other SOC units */ +#define pr_fmt(fmt) "mvebu-pmsu: " fmt + #include #include #include @@ -63,15 +65,39 @@ int armada_xp_boot_cpu(unsigned int cpu_id, void *boot_addr) static int __init armada_370_xp_pmsu_init(void) { struct device_node *np; + struct resource res; + int ret = 0; np = of_find_matching_node(NULL, of_pmsu_table); - if (np) { - pr_info("Initializing Power Management Service Unit\n"); - pmsu_mp_base = of_iomap(np, 0); - of_node_put(np); + if (!np) + return 0; + + pr_info("Initializing Power Management Service Unit\n"); + + if (of_address_to_resource(np, 0, &res)) { + pr_err("unable to get resource\n"); + ret = -ENOENT; + goto out; } - return 0; + if (!request_mem_region(res.start, resource_size(&res), + np->full_name)) { + pr_err("unable to request region\n"); + ret = -EBUSY; + goto out; + } + + pmsu_mp_base = ioremap(res.start, resource_size(&res)); + if (!pmsu_mp_base) { + pr_err("unable to map registers\n"); + release_mem_region(res.start, resource_size(&res)); + ret = -ENOMEM; + goto out; + } + + out: + of_node_put(np); + return ret; } early_initcall(armada_370_xp_pmsu_init); From 0c3acc746d2cd84c3654b6cc07eda2411584f4af Mon Sep 17 00:00:00 2001 From: Gregory CLEMENT Date: Mon, 14 Apr 2014 15:50:31 +0200 Subject: [PATCH 4/5] ARM: mvebu: extend the PMSU registers The initial binding for PMSU was wrong, as it didn't take into account all the registers from the PMSU and moreover it referred to the CPU reset registers which are not part of PMSU. The Power Management Unit Service block also controls the Coherency Fabric subsystem. These registers are needed for the CPU idle implementation for the Armada 370/XP, it allows to enter a deep CPU idle state where the Coherency Fabric and the L2 cache are powered down. This commit adds support for a new compatible for the PMSU node which includes the registers related to the coherency fabric. It also keeps compatibility with the old compatible string. Signed-off-by: Gregory CLEMENT Link: https://lkml.kernel.org/r/1397483433-25836-5-git-send-email-thomas.petazzoni@free-electrons.com Signed-off-by: Thomas Petazzoni Link: https://lkml.kernel.org/r/1397483433-25836-5-git-send-email-thomas.petazzoni@free-electrons.com Signed-off-by: Jason Cooper --- .../devicetree/bindings/arm/armada-370-xp-pmsu.txt | 14 ++++++-------- arch/arm/mach-mvebu/pmsu.c | 14 ++++++++++++-- 2 files changed, 18 insertions(+), 10 deletions(-) diff --git a/Documentation/devicetree/bindings/arm/armada-370-xp-pmsu.txt b/Documentation/devicetree/bindings/arm/armada-370-xp-pmsu.txt index 926b4d6aae7e..976188770079 100644 --- a/Documentation/devicetree/bindings/arm/armada-370-xp-pmsu.txt +++ b/Documentation/devicetree/bindings/arm/armada-370-xp-pmsu.txt @@ -4,17 +4,15 @@ Available on Marvell SOCs: Armada 370 and Armada XP Required properties: -- compatible: "marvell,armada-370-xp-pmsu" +- compatible: should be "marvell,armada-370-pmsu", whereas + "marvell,armada-370-xp-pmsu" is deprecated and will be removed -- reg: Should contain PMSU registers location and length. First pair - for the per-CPU SW Reset Control registers, second pair for the - Power Management Service Unit. +- reg: Should contain PMSU registers location and length. Example: -armada-370-xp-pmsu@d0022000 { - compatible = "marvell,armada-370-xp-pmsu"; - reg = <0xd0022100 0x430>, - <0xd0020800 0x20>; +armada-370-xp-pmsu@22000 { + compatible = "marvell,armada-370-pmsu"; + reg = <0x22000 0x1000>; }; diff --git a/arch/arm/mach-mvebu/pmsu.c b/arch/arm/mach-mvebu/pmsu.c index b337fe56bae5..4ae3ea1af7c3 100644 --- a/arch/arm/mach-mvebu/pmsu.c +++ b/arch/arm/mach-mvebu/pmsu.c @@ -30,10 +30,14 @@ static void __iomem *pmsu_mp_base; -#define PMSU_BOOT_ADDR_REDIRECT_OFFSET(cpu) ((cpu * 0x100) + 0x24) +#define PMSU_BASE_OFFSET 0x100 +#define PMSU_REG_SIZE 0x1000 + +#define PMSU_BOOT_ADDR_REDIRECT_OFFSET(cpu) ((cpu * 0x100) + 0x124) static struct of_device_id of_pmsu_table[] = { - {.compatible = "marvell,armada-370-xp-pmsu"}, + { .compatible = "marvell,armada-370-pmsu", }, + { .compatible = "marvell,armada-370-xp-pmsu", }, { /* end of list */ }, }; @@ -80,6 +84,12 @@ static int __init armada_370_xp_pmsu_init(void) goto out; } + if (of_device_is_compatible(np, "marvell,armada-370-xp-pmsu")) { + pr_warn(FW_WARN "deprecated pmsu binding\n"); + res.start = res.start - PMSU_BASE_OFFSET; + res.end = res.start + PMSU_REG_SIZE - 1; + } + if (!request_mem_region(res.start, resource_size(&res), np->full_name)) { pr_err("unable to request region\n"); From 02e7b06795fc129e45ed39983673efbb05d69506 Mon Sep 17 00:00:00 2001 From: Gregory CLEMENT Date: Mon, 14 Apr 2014 15:50:33 +0200 Subject: [PATCH 5/5] ARM: mvebu: use a separate function to set the boot address of CPUs Setting the start (or boot) address of a CPU is no more used only during SMP bring up on Armada 370/XP, but it will also be used by the CPU idle function of Armada XP, and by the Armada 38x SMP support. Therefore this commit creates a separate PMSU function to set the boot address of a CPU with the PMSU. Signed-off-by: Gregory CLEMENT Link: https://lkml.kernel.org/r/1397483433-25836-7-git-send-email-thomas.petazzoni@free-electrons.com Signed-off-by: Thomas Petazzoni Link: https://lkml.kernel.org/r/1397483433-25836-7-git-send-email-thomas.petazzoni@free-electrons.com Signed-off-by: Jason Cooper --- arch/arm/mach-mvebu/pmsu.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/arch/arm/mach-mvebu/pmsu.c b/arch/arm/mach-mvebu/pmsu.c index 4ae3ea1af7c3..8361281f9180 100644 --- a/arch/arm/mach-mvebu/pmsu.c +++ b/arch/arm/mach-mvebu/pmsu.c @@ -41,6 +41,12 @@ static struct of_device_id of_pmsu_table[] = { { /* end of list */ }, }; +static void mvebu_pmsu_set_cpu_boot_addr(int hw_cpu, void *boot_addr) +{ + writel(virt_to_phys(boot_addr), pmsu_mp_base + + PMSU_BOOT_ADDR_REDIRECT_OFFSET(hw_cpu)); +} + #ifdef CONFIG_SMP int armada_xp_boot_cpu(unsigned int cpu_id, void *boot_addr) { @@ -53,8 +59,7 @@ int armada_xp_boot_cpu(unsigned int cpu_id, void *boot_addr) hw_cpu = cpu_logical_map(cpu_id); - writel(virt_to_phys(boot_addr), pmsu_mp_base + - PMSU_BOOT_ADDR_REDIRECT_OFFSET(hw_cpu)); + mvebu_pmsu_set_cpu_boot_addr(hw_cpu, boot_addr); ret = mvebu_cpu_reset_deassert(hw_cpu); if (ret) {