On Wed, Mar 18, 2015 at 6:29 PM, Maxime Ripard <maxime.rip...@free-electrons.com> wrote: > On Wed, Mar 18, 2015 at 11:24:01AM +0800, Chen-Yu Tsai wrote: >> The A23 is a dual Cortex-A7. Add the logic to use the IPs used to >> control the CPU configuration and the CPU power so that we can >> bring up secondary CPUs at boot. >> >> Signed-off-by: Chen-Yu Tsai <w...@csie.org> >> --- >> >> We can't use of_io_request_and_map() here, as it will conflict >> with PRCM, and leave us without a serial console. >> >> I think a proper way to solve this would be a syscon device or >> something like the mfd-simple device posted by Arnd. >> >> --- >> Documentation/devicetree/bindings/arm/cpus.txt | 1 + >> arch/arm/mach-sunxi/platsmp.c | 69 >> ++++++++++++++++++++++++++ >> 2 files changed, 70 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/arm/cpus.txt >> b/Documentation/devicetree/bindings/arm/cpus.txt >> index 8b9e0a95de31..40202d85b132 100644 >> --- a/Documentation/devicetree/bindings/arm/cpus.txt >> +++ b/Documentation/devicetree/bindings/arm/cpus.txt >> @@ -188,6 +188,7 @@ nodes to be present and contain the properties described >> below. >> # On ARM 32-bit systems this property is optional and >> can be one of: >> "allwinner,sun6i-a31" >> + "allwinner,sun8i-a23" >> "arm,psci" >> "brcm,brahma-b15" >> "marvell,armada-375-smp" >> diff --git a/arch/arm/mach-sunxi/platsmp.c b/arch/arm/mach-sunxi/platsmp.c >> index 587b0468efcc..e8483ec79d67 100644 >> --- a/arch/arm/mach-sunxi/platsmp.c >> +++ b/arch/arm/mach-sunxi/platsmp.c >> @@ -121,3 +121,72 @@ static struct smp_operations sun6i_smp_ops __initdata = >> { >> .smp_boot_secondary = sun6i_smp_boot_secondary, >> }; >> CPU_METHOD_OF_DECLARE(sun6i_a31_smp, "allwinner,sun6i-a31", &sun6i_smp_ops); >> + >> +static void __init sun8i_smp_prepare_cpus(unsigned int max_cpus) >> +{ >> + struct device_node *node; >> + >> + node = of_find_compatible_node(NULL, NULL, "allwinner,sun8i-a23-prcm"); >> + if (!node) { >> + pr_err("Missing A23 PRCM node in the device tree\n"); >> + return; >> + } >> + >> + prcm_membase = of_iomap(node, 0); >> + if (!prcm_membase) { >> + pr_err("Couldn't map A23 PRCM registers\n"); >> + return; >> + } >> + >> + node = of_find_compatible_node(NULL, NULL, >> + "allwinner,sun8i-a23-cpuconfig"); >> + if (!node) { >> + pr_err("Missing A23 CPU config node in the device tree\n"); >> + return; >> + } >> + >> + cpucfg_membase = of_iomap(node, 0); >> + if (!cpucfg_membase) >> + pr_err("Couldn't map A23 CPU config registers\n"); >> + >> +} >> + >> +static int sun8i_smp_boot_secondary(unsigned int cpu, >> + struct task_struct *idle) >> +{ >> + u32 reg; >> + >> + if (!(prcm_membase && cpucfg_membase)) >> + return -EFAULT; >> + >> + spin_lock(&cpu_lock); >> + >> + /* Set CPU boot address */ >> + writel(virt_to_phys(secondary_startup), >> + cpucfg_membase + CPUCFG_PRIVATE0_REG); > > One question I couldn't find any answer to is that does the SMP bit is > set in secondary_startup? > > I couldn't find where it was set, but it still looks like the right > thing to do, so I would expect the code to do that.
I don't see it either. The sun8i code is just the sun6i code with the power clamps removed. And sun6i secondary_startup was removed some time ago in commit 1146b600044d ("ARM: sunxi: fix build for THUMB2_KERNEL"). ChenYu -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to linux-sunxi+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.