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ARM: sun8i: Add SMP support for the Allwinner A23 

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 <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
This commit is contained in:
Chen-Yu Tsai 2015-03-18 11:24:01 +08:00 committed by Maxime Ripard
parent b787f68c36
commit 7917d14129
2 changed files with 70 additions and 0 deletions
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1
Documentation/devicetree/bindings/arm/cpus.txt
View File

@ -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"

69
arch/arm/mach-sunxi/platsmp.c
View File

@ -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);
/* Assert the CPU core in reset */
writel(0, cpucfg_membase + CPUCFG_CPU_RST_CTRL_REG(cpu));
/* Assert the L1 cache in reset */
reg = readl(cpucfg_membase + CPUCFG_GEN_CTRL_REG);
writel(reg & ~BIT(cpu), cpucfg_membase + CPUCFG_GEN_CTRL_REG);
/* Clear CPU power-off gating */
reg = readl(prcm_membase + PRCM_CPU_PWROFF_REG);
writel(reg & ~BIT(cpu), prcm_membase + PRCM_CPU_PWROFF_REG);
mdelay(1);
/* Deassert the CPU core reset */
writel(3, cpucfg_membase + CPUCFG_CPU_RST_CTRL_REG(cpu));
spin_unlock(&cpu_lock);
return 0;
}
struct smp_operations sun8i_smp_ops __initdata = {
.smp_prepare_cpus = sun8i_smp_prepare_cpus,
.smp_boot_secondary = sun8i_smp_boot_secondary,
};
CPU_METHOD_OF_DECLARE(sun8i_a23_smp, "allwinner,sun8i-a23", &sun8i_smp_ops);