diff options
| -rw-r--r-- | Documentation/devicetree/booting-without-of.txt | 13 | ||||
| -rw-r--r-- | arch/sh/boards/Kconfig | 15 | ||||
| -rw-r--r-- | arch/sh/boards/Makefile | 2 | ||||
| -rw-r--r-- | arch/sh/boards/of-generic.c | 113 | ||||
| -rw-r--r-- | arch/sh/kernel/head_32.S | 13 | ||||
| -rw-r--r-- | arch/sh/kernel/setup.c | 27 |
6 files changed, 183 insertions, 0 deletions
diff --git a/Documentation/devicetree/booting-without-of.txt b/Documentation/devicetree/booting-without-of.txt index 04d34f6a58f3..3f1437fbca6b 100644 --- a/Documentation/devicetree/booting-without-of.txt +++ b/Documentation/devicetree/booting-without-of.txt @@ -16,6 +16,7 @@ Table of Contents 2) Entry point for arch/powerpc 3) Entry point for arch/x86 4) Entry point for arch/mips/bmips + 5) Entry point for arch/sh II - The DT block format 1) Header @@ -316,6 +317,18 @@ it with special cases. This convention is defined for 32-bit systems only, as there are not currently any 64-bit BMIPS implementations. +5) Entry point for arch/sh +-------------------------- + + Device-tree-compatible SH bootloaders are expected to provide the physical + address of the device tree blob in r4. Since legacy bootloaders did not + guarantee any particular initial register state, kernels built to + inter-operate with old bootloaders must either use a builtin DTB or + select a legacy board option (something other than CONFIG_SH_DEVICE_TREE) + that does not use device tree. Support for the latter is being phased out + in favor of device tree. + + II - The DT block format ======================== diff --git a/arch/sh/boards/Kconfig b/arch/sh/boards/Kconfig index 89963d13f930..5e52d5362292 100644 --- a/arch/sh/boards/Kconfig +++ b/arch/sh/boards/Kconfig @@ -6,6 +6,21 @@ config SOLUTION_ENGINE config SH_ALPHA_BOARD bool +config SH_DEVICE_TREE + bool "Board Described by Device Tree" + select OF + select OF_EARLY_FLATTREE + select CLKSRC_OF + select GENERIC_CALIBRATE_DELAY + help + Select Board Described by Device Tree to build a kernel that + does not hard-code any board-specific knowledge but instead uses + a device tree blob provided by the boot-loader. You must enable + drivers for any hardware you want to use separately. At this + time, only boards based on the open-hardware J-Core processors + have sufficient driver coverage to use this option; do not + select it if you are using original SuperH hardware. + config SH_SOLUTION_ENGINE bool "SolutionEngine" select SOLUTION_ENGINE diff --git a/arch/sh/boards/Makefile b/arch/sh/boards/Makefile index 975a0f64ff20..cea300362035 100644 --- a/arch/sh/boards/Makefile +++ b/arch/sh/boards/Makefile @@ -15,3 +15,5 @@ obj-$(CONFIG_SH_TITAN) += board-titan.o obj-$(CONFIG_SH_SH7757LCR) += board-sh7757lcr.o obj-$(CONFIG_SH_APSH4A3A) += board-apsh4a3a.o obj-$(CONFIG_SH_APSH4AD0A) += board-apsh4ad0a.o + +obj-$(CONFIG_SH_DEVICE_TREE) += of-generic.o diff --git a/arch/sh/boards/of-generic.c b/arch/sh/boards/of-generic.c new file mode 100644 index 000000000000..71d890932151 --- /dev/null +++ b/arch/sh/boards/of-generic.c @@ -0,0 +1,113 @@ +/* + * SH generic board support, using device tree + * + * Copyright (C) 2015-2016 Smart Energy Instruments, Inc. + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ + +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/of_fdt.h> +#include <linux/of_iommu.h> +#include <linux/clocksource.h> +#include <linux/irqchip.h> +#include <linux/clk-provider.h> +#include <asm/machvec.h> +#include <asm/rtc.h> + +static void noop(void) +{ +} + +static int noopi(void) +{ + return 0; +} + +static void __init sh_of_mem_reserve(void) +{ + early_init_fdt_reserve_self(); + early_init_fdt_scan_reserved_mem(); +} + +static void __init sh_of_time_init(void) +{ + pr_info("SH generic board support: scanning for clocksource devices\n"); + clocksource_probe(); +} + +static void __init sh_of_setup(char **cmdline_p) +{ + unflatten_device_tree(); + + board_time_init = sh_of_time_init; + + sh_mv.mv_name = of_flat_dt_get_machine_name(); + if (!sh_mv.mv_name) + sh_mv.mv_name = "Unknown SH model"; + + /* FIXME: register smp ops to use dt to find cpus, use + * cpu enable-method, and use irq controller's ipi + * functions. */ +} + +static int sh_of_irq_demux(int irq) +{ + /* FIXME: eventually this should not be used at all; + * the interrupt controller should set_handle_irq(). */ + return irq; +} + +static void __init sh_of_init_irq(void) +{ + pr_info("SH generic board support: scanning for interrupt controllers\n"); + irqchip_init(); +} + +static int __init sh_of_clk_init(void) +{ +#ifdef CONFIG_COMMON_CLK + /* Disabled pending move to COMMON_CLK framework. */ + pr_info("SH generic board support: scanning for clk providers\n"); + of_clk_init(NULL); +#endif + return 0; +} + +static struct sh_machine_vector __initmv sh_of_generic_mv = { + .mv_setup = sh_of_setup, + .mv_name = "devicetree", /* replaced by DT root's model */ + .mv_irq_demux = sh_of_irq_demux, + .mv_init_irq = sh_of_init_irq, + .mv_clk_init = sh_of_clk_init, + .mv_mode_pins = noopi, + .mv_mem_init = noop, + .mv_mem_reserve = sh_of_mem_reserve, +}; + +struct sh_clk_ops; + +void __init arch_init_clk_ops(struct sh_clk_ops **ops, int idx) +{ +} + +void __init plat_irq_setup(void) +{ +} + +static int __init sh_of_device_init(void) +{ + pr_info("SH generic board support: populating platform devices\n"); + if (of_have_populated_dt()) { + of_iommu_init(); + of_platform_populate(NULL, of_default_bus_match_table, + NULL, NULL); + } else { + pr_crit("Device tree not populated\n"); + } + return 0; +} +arch_initcall_sync(sh_of_device_init); diff --git a/arch/sh/kernel/head_32.S b/arch/sh/kernel/head_32.S index 7db248936b60..974bc152cc84 100644 --- a/arch/sh/kernel/head_32.S +++ b/arch/sh/kernel/head_32.S @@ -66,6 +66,10 @@ ENTRY(_stext) mov #0, r0 ldc r0, r6_bank #endif + +#ifdef CONFIG_OF + mov r4, r12 ! Store device tree blob pointer in r12 +#endif /* * Prefetch if possible to reduce cache miss penalty. @@ -314,6 +318,12 @@ ENTRY(_stext) 10: #endif +#ifdef CONFIG_OF + mov.l 8f, r0 ! Make flat device tree available early. + jsr @r0 + mov r12, r4 +#endif + ! Additional CPU initialization mov.l 6f, r0 jsr @r0 @@ -339,6 +349,9 @@ ENTRY(stack_start) 5: .long start_kernel 6: .long cpu_init 7: .long init_thread_union +#if defined(CONFIG_OF) +8: .long sh_fdt_init +#endif #ifdef CONFIG_PMB .LPMB_ADDR: .long PMB_ADDR diff --git a/arch/sh/kernel/setup.c b/arch/sh/kernel/setup.c index de19cfa768f2..efb60ce720a7 100644 --- a/arch/sh/kernel/setup.c +++ b/arch/sh/kernel/setup.c @@ -29,6 +29,8 @@ #include <linux/delay.h> #include <linux/platform_device.h> #include <linux/memblock.h> +#include <linux/of.h> +#include <linux/of_fdt.h> #include <asm/uaccess.h> #include <asm/io.h> #include <asm/page.h> @@ -172,6 +174,7 @@ disable: #endif } +#ifndef CONFIG_GENERIC_CALIBRATE_DELAY void calibrate_delay(void) { struct clk *clk = clk_get(NULL, "cpu_clk"); @@ -187,6 +190,7 @@ void calibrate_delay(void) (loops_per_jiffy/(5000/HZ)) % 100, loops_per_jiffy); } +#endif void __init __add_active_range(unsigned int nid, unsigned long start_pfn, unsigned long end_pfn) @@ -238,6 +242,29 @@ void __init __weak plat_early_device_setup(void) { } +#ifdef CONFIG_OF +void __ref sh_fdt_init(phys_addr_t dt_phys) +{ + static int done = 0; + void *dt_virt; + + /* Avoid calling an __init function on secondary cpus. */ + if (done) return; + + dt_virt = phys_to_virt(dt_phys); + + if (!dt_virt || !early_init_dt_scan(dt_virt)) { + pr_crit("Error: invalid device tree blob" + " at physical address %p\n", (void *)dt_phys); + + while (true) + cpu_relax(); + } + + done = 1; +} +#endif + void __init setup_arch(char **cmdline_p) { enable_mmu(); |