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authorDaniel Palmer <daniel@0x0f.com>2020-12-01 22:43:30 +0900
committerArnd Bergmann <arnd@arndb.de>2020-12-09 17:45:40 +0100
commit5919eec0f09214901b09faeaf6341addebc57a89 (patch)
tree16397de3597a073bea7cf74a586bcc6a66b9ff43 /arch/arm/mach-mstar
parentecaafac1eb73de8209680ec030769a2def4801e5 (diff)
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ARM: mstar: SMP support
This patch adds SMP support for MStar/Sigmastar chips that have a second core like those in the infinity2m family. So far only single and dual core chips have been found so this does the bare minimum to boot the second core. From what I can tell not having the "holding pen" code to handle multiple cores is fine if there is only one core the will get booted. This might need to be reconsidered if chips with more cores turn up. Signed-off-by: Daniel Palmer <daniel@0x0f.com> Link: https://lore.kernel.org/r/20201201134330.3037007-11-daniel@0x0f.com' Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'arch/arm/mach-mstar')
-rw-r--r--arch/arm/mach-mstar/mstarv7.c48
1 files changed, 48 insertions, 0 deletions
diff --git a/arch/arm/mach-mstar/mstarv7.c b/arch/arm/mach-mstar/mstarv7.c
index 1aa748fa006e..274c4f0df270 100644
--- a/arch/arm/mach-mstar/mstarv7.c
+++ b/arch/arm/mach-mstar/mstarv7.c
@@ -31,6 +31,13 @@
#define MSTARV7_L3BRIDGE_FLUSH_TRIGGER BIT(0)
#define MSTARV7_L3BRIDGE_STATUS_DONE BIT(12)
+#ifdef CONFIG_SMP
+#define MSTARV7_CPU1_BOOT_ADDR_HIGH 0x4c
+#define MSTARV7_CPU1_BOOT_ADDR_LOW 0x50
+#define MSTARV7_CPU1_UNLOCK 0x58
+#define MSTARV7_CPU1_UNLOCK_MAGIC 0xbabe
+#endif
+
static void __iomem *l3bridge;
static const char * const mstarv7_board_dt_compat[] __initconst = {
@@ -63,6 +70,46 @@ static void mstarv7_mb(void)
}
}
+#ifdef CONFIG_SMP
+static int mstarv7_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+ struct device_node *np;
+ u32 bootaddr = (u32) __pa_symbol(secondary_startup_arm);
+ void __iomem *smpctrl;
+
+ /*
+ * right now we don't know how to boot anything except
+ * cpu 1.
+ */
+ if (cpu != 1)
+ return -EINVAL;
+
+ np = of_find_compatible_node(NULL, NULL, "mstar,smpctrl");
+ smpctrl = of_iomap(np, 0);
+
+ if (!smpctrl)
+ return -ENODEV;
+
+ /* set the boot address for the second cpu */
+ writew(bootaddr & 0xffff, smpctrl + MSTARV7_CPU1_BOOT_ADDR_LOW);
+ writew((bootaddr >> 16) & 0xffff, smpctrl + MSTARV7_CPU1_BOOT_ADDR_HIGH);
+
+ /* unlock the second cpu */
+ writew(MSTARV7_CPU1_UNLOCK_MAGIC, smpctrl + MSTARV7_CPU1_UNLOCK);
+
+ /* and away we go...*/
+ arch_send_wakeup_ipi_mask(cpumask_of(cpu));
+
+ iounmap(smpctrl);
+
+ return 0;
+}
+
+static const struct smp_operations __initdata mstarv7_smp_ops = {
+ .smp_boot_secondary = mstarv7_boot_secondary,
+};
+#endif
+
static void __init mstarv7_init(void)
{
struct device_node *np;
@@ -78,4 +125,5 @@ static void __init mstarv7_init(void)
DT_MACHINE_START(MSTARV7_DT, "MStar/Sigmastar Armv7 (Device Tree)")
.dt_compat = mstarv7_board_dt_compat,
.init_machine = mstarv7_init,
+ .smp = smp_ops(mstarv7_smp_ops),
MACHINE_END