From mboxrd@z Thu Jan 1 00:00:00 1970 From: chris.packham@alliedtelesis.co.nz (Chris Packham) Date: Fri, 12 Dec 2014 17:53:55 +1300 Subject: [RFC/PATCH 1/4 PATCH] ARM: mvebu: use dt_fixup to provide fallback for enable-method In-Reply-To: <5488A2C0.5040804@alliedtelesis.co.nz> References: <5488A2C0.5040804@alliedtelesis.co.nz> Message-ID: <1418360035-27975-1-git-send-email-chris.packham@alliedtelesis.co.nz> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Arnd, > On 12/10/2014 10:44 PM, Arnd Bergmann wrote: >> On Wednesday 10 December 2014 15:39:44 Chris Packham wrote: >>> >>> +static void __init armada_370_xp_dt_fixup(void) >>> +{ >>> + smp_set_ops(smp_ops(armada_xp_smp_ops)); >>> +} >>> + >>> >> >> The dt_fixup callback pointer is meant to fix up a legacy dtb file in >> memory. I think this would be fairly easy in this case, just add in the >> missing enable-method property here to make the normal boot path >> work for old dtbs. >> >> Arnd >> > > I briefly explored that approach here[1]. The tricky part would be > handling the fact that the enable method can be attached to either the > /cpus node or and individual /cpu entry (or is that something I can > ignore?). > > In the end I thought that the unconditional setting of smp_ops was > easier to implement and would achieve the same result. Actually as it turns out it's not that hard to implement something that checks both /cpus and /cpus/cpu at n. I'll include this with the next round after I've waited for anymore feedback. ---8<--- Subject: [PATCH] ARM: mvebu: use dt_fixup to provide fallback for enable-method When the device tree doesn't define an enable-method insert a property into the flattened device tree. arm_dt_init_cpu_maps() will then parse this an set smp_ops appropriately. Now that we have this fallback it is no longer necessary to set .smp in the DT_MACHINE definition. Signed-off-by: Chris Packham --- arch/arm/mach-mvebu/Makefile | 2 ++ arch/arm/mach-mvebu/board-v7.c | 37 ++++++++++++++++++++++++++++++++++++- 2 files changed, 38 insertions(+), 1 deletion(-) diff --git a/arch/arm/mach-mvebu/Makefile b/arch/arm/mach-mvebu/Makefile index e24136b..68310f8 100644 --- a/arch/arm/mach-mvebu/Makefile +++ b/arch/arm/mach-mvebu/Makefile @@ -14,3 +14,5 @@ endif obj-$(CONFIG_MACH_DOVE) += dove.o obj-$(CONFIG_MACH_KIRKWOOD) += kirkwood.o kirkwood-pm.o obj-$(CONFIG_MACH_NETXBIG) += netxbig.o + +CFLAGS_board-v7.o = -I$(src)/../../../scripts/dtc/libfdt \ No newline at end of file diff --git a/arch/arm/mach-mvebu/board-v7.c b/arch/arm/mach-mvebu/board-v7.c index d0d39f1..0592c76 100644 --- a/arch/arm/mach-mvebu/board-v7.c +++ b/arch/arm/mach-mvebu/board-v7.c @@ -17,6 +17,8 @@ #include #include #include +#include +#include #include #include #include @@ -198,6 +200,39 @@ static void __init mvebu_dt_init(void) of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL); } +static void __init armada_370_xp_dt_fixup(void) +{ + int offset, node; + int i, len; + void *prop; + char buffer[20]; + + offset = fdt_path_offset(initial_boot_params, "/cpus"); + if (offset < 0) + return; + + prop = fdt_getprop(initial_boot_params, offset, "enable-method", &len); + if (prop) + return; + + for (i = 0; i < NR_CPUS; i++) { + snprintf(buffer, sizeof(buffer), "cpu@%d", i); + node = fdt_subnode_offset(initial_boot_params, offset, buffer); + if (node < 0) + break; + prop = fdt_getprop(initial_boot_params, node, + "enable-method", &len); + if (prop) + return; + } + + pr_info("No enable-method defined. " + "Falling back to \"marvell,armada-xp-smp\"\n"); + + fdt_setprop(initial_boot_params, offset, "enable-method", + "marvell,armada-xp-smp", sizeof("marvell,armada-xp-smp")); +} + static const char * const armada_370_xp_dt_compat[] = { "marvell,armada-370-xp", NULL, @@ -206,11 +241,11 @@ static const char * const armada_370_xp_dt_compat[] = { DT_MACHINE_START(ARMADA_370_XP_DT, "Marvell Armada 370/XP (Device Tree)") .l2c_aux_val = 0, .l2c_aux_mask = ~0, - .smp = smp_ops(armada_xp_smp_ops), .init_machine = mvebu_dt_init, .init_irq = mvebu_init_irq, .restart = mvebu_restart, .dt_compat = armada_370_xp_dt_compat, + .dt_fixup = armada_370_xp_dt_fixup, MACHINE_END static const char * const armada_375_dt_compat[] = { -- 2.2.0.rc0