From 4b049a6b275db68c2c028937b89abd732dcdf536 Mon Sep 17 00:00:00 2001 From: Kevin Cernekee Date: Thu, 25 Dec 2014 09:49:14 -0800 Subject: [PATCH] MIPS: BMIPS: Add quirks for several Broadcom platforms A couple of chips require special handling in order to make SMP secondary boot and/or exception vectors work correctly. Take care of these in setup.c. Signed-off-by: Kevin Cernekee Cc: f.fainelli@gmail.com Cc: jaedon.shin@gmail.com Cc: abrestic@chromium.org Cc: tglx@linutronix.de Cc: jason@lakedaemon.net Cc: jogo@openwrt.org Cc: arnd@arndb.de Cc: computersforpeace@gmail.com Cc: linux-mips@linux-mips.org Cc: devicetree@vger.kernel.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/8852/ Signed-off-by: Ralf Baechle --- arch/mips/bmips/setup.c | 101 +++++++++++++++++++++++++++++++++++++++- 1 file changed, 99 insertions(+), 2 deletions(-) diff --git a/arch/mips/bmips/setup.c b/arch/mips/bmips/setup.c index ac402ed8443b..fae800e8b1e1 100644 --- a/arch/mips/bmips/setup.c +++ b/arch/mips/bmips/setup.c @@ -8,9 +8,12 @@ */ #include +#include #include #include #include +#include +#include #include #include #include @@ -18,9 +21,92 @@ #include #include #include +#include +#include #include #include #include +#include + +#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) { @@ -53,7 +139,8 @@ void __init plat_time_init(void) void __init plat_mem_setup(void) { - void *dtb = __dtb_start; + void *dtb; + const struct bmips_quirk *q; set_io_port_base(0); ioport_resource.start = 0; @@ -62,10 +149,20 @@ void __init plat_mem_setup(void) /* 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) -- 2.20.1