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Diffstat (limited to 'kernel/arch/mips/bmips/setup.c')
| -rw-r--r-- | kernel/arch/mips/bmips/setup.c | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/kernel/arch/mips/bmips/setup.c b/kernel/arch/mips/bmips/setup.c new file mode 100644 index 000000000..fae800e8b --- /dev/null +++ b/kernel/arch/mips/bmips/setup.c @@ -0,0 +1,194 @@ +/* + * 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. + * + * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr> + * Copyright (C) 2014 Kevin Cernekee <cernekee@gmail.com> + */ + +#include <linux/init.h> +#include <linux/bitops.h> +#include <linux/bootmem.h> +#include <linux/clk-provider.h> +#include <linux/ioport.h> +#include <linux/kernel.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_fdt.h> +#include <linux/of_platform.h> +#include <linux/smp.h> +#include <asm/addrspace.h> +#include <asm/bmips.h> +#include <asm/bootinfo.h> +#include <asm/cpu-type.h> +#include <asm/mipsregs.h> +#include <asm/prom.h> +#include <asm/smp-ops.h> +#include <asm/time.h> +#include <asm/traps.h> + +#define RELO_NORMAL_VEC BIT(18) + +#define REG_BCM6328_OTP ((void __iomem *)CKSEG1ADDR(0x1000062c)) +#define BCM6328_TP1_DISABLED BIT(9) + +static const unsigned long kbase = VMLINUX_LOAD_ADDRESS & 0xfff00000; + +struct bmips_quirk { + const char *compatible; + void (*quirk_fn)(void); +}; + +static void kbase_setup(void) +{ + __raw_writel(kbase | RELO_NORMAL_VEC, + BMIPS_GET_CBR() + BMIPS_RELO_VECTOR_CONTROL_1); + ebase = kbase; +} + +static void bcm3384_viper_quirks(void) +{ + /* + * Some experimental CM boxes are set up to let CM own the Viper TP0 + * and let Linux own TP1. This requires moving the kernel + * load address to a non-conflicting region (e.g. via + * CONFIG_PHYSICAL_START) and supplying an alternate DTB. + * If we detect this condition, we need to move the MIPS exception + * vectors up to an area that we own. + * + * This is distinct from the OTHER special case mentioned in + * smp-bmips.c (boot on TP1, but enable SMP, then TP0 becomes our + * logical CPU#1). For the Viper TP1 case, SMP is off limits. + * + * Also note that many BMIPS435x CPUs do not have a + * BMIPS_RELO_VECTOR_CONTROL_1 register, so it isn't safe to just + * write VMLINUX_LOAD_ADDRESS into that register on every SoC. + */ + board_ebase_setup = &kbase_setup; + bmips_smp_enabled = 0; +} + +static void bcm63xx_fixup_cpu1(void) +{ + /* + * The bootloader has set up the CPU1 reset vector at + * 0xa000_0200. + * This conflicts with the special interrupt vector (IV). + * The bootloader has also set up CPU1 to respond to the wrong + * IPI interrupt. + * Here we will start up CPU1 in the background and ask it to + * reconfigure itself then go back to sleep. + */ + memcpy((void *)0xa0000200, &bmips_smp_movevec, 0x20); + __sync(); + set_c0_cause(C_SW0); + cpumask_set_cpu(1, &bmips_booted_mask); +} + +static void bcm6328_quirks(void) +{ + /* Check CPU1 status in OTP (it is usually disabled) */ + if (__raw_readl(REG_BCM6328_OTP) & BCM6328_TP1_DISABLED) + bmips_smp_enabled = 0; + else + bcm63xx_fixup_cpu1(); +} + +static void bcm6368_quirks(void) +{ + bcm63xx_fixup_cpu1(); +} + +static const struct bmips_quirk bmips_quirk_list[] = { + { "brcm,bcm3384-viper", &bcm3384_viper_quirks }, + { "brcm,bcm33843-viper", &bcm3384_viper_quirks }, + { "brcm,bcm6328", &bcm6328_quirks }, + { "brcm,bcm6368", &bcm6368_quirks }, + { }, +}; + +void __init prom_init(void) +{ + register_bmips_smp_ops(); +} + +void __init prom_free_prom_memory(void) +{ +} + +const char *get_system_type(void) +{ + return "Generic BMIPS kernel"; +} + +void __init plat_time_init(void) +{ + struct device_node *np; + u32 freq; + + np = of_find_node_by_name(NULL, "cpus"); + if (!np) + panic("missing 'cpus' DT node"); + if (of_property_read_u32(np, "mips-hpt-frequency", &freq) < 0) + panic("missing 'mips-hpt-frequency' property"); + of_node_put(np); + + mips_hpt_frequency = freq; +} + +void __init plat_mem_setup(void) +{ + void *dtb; + const struct bmips_quirk *q; + + set_io_port_base(0); + ioport_resource.start = 0; + ioport_resource.end = ~0; + + /* intended to somewhat resemble ARM; see Documentation/arm/Booting */ + if (fw_arg0 == 0 && fw_arg1 == 0xffffffff) + dtb = phys_to_virt(fw_arg2); + else if (__dtb_start != __dtb_end) + dtb = (void *)__dtb_start; + else + panic("no dtb found"); + + __dt_setup_arch(dtb); + strlcpy(arcs_cmdline, boot_command_line, COMMAND_LINE_SIZE); + + for (q = bmips_quirk_list; q->quirk_fn; q++) { + if (of_flat_dt_is_compatible(of_get_flat_dt_root(), + q->compatible)) { + q->quirk_fn(); + } + } +} + +void __init device_tree_init(void) +{ + struct device_node *np; + + unflatten_and_copy_device_tree(); + + /* Disable SMP boot unless both CPUs are listed in DT and !disabled */ + np = of_find_node_by_name(NULL, "cpus"); + if (np && of_get_available_child_count(np) <= 1) + bmips_smp_enabled = 0; + of_node_put(np); +} + +int __init plat_of_setup(void) +{ + return __dt_register_buses("simple-bus", NULL); +} + +arch_initcall(plat_of_setup); + +static int __init plat_dev_init(void) +{ + of_clk_init(NULL); + return 0; +} + +device_initcall(plat_dev_init); |