ARM: mvebu: add function to set the resume boot address for Armada 375

In order to boot the secondary CPUs on Armada 375, we need to set the
boot address of these CPUs, through a register part of the System
Controller (this deviates from the Armada XP design, where the boot
address was defined using a register part of the PMSU unit).

Therefore, this commit adds a new helper function in the System
Controller driver to set the secondary CPU boot address.

Moreover, it moves the System Controller initialization as an
early_initcall(), since arch_initcall() is too late for an SMP-related
initialization.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Link: https://lkml.kernel.org/r/1397483648-26611-7-git-send-email-thomas.petazzoni@free-electrons.com
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1397483648-26611-7-git-send-email-thomas.petazzoni@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

arch/arm/mach-mvebu/common.h

@@ -20,6 +20,7 @@
 void mvebu_restart(enum reboot_mode mode, const char *cmd);
 int mvebu_cpu_reset_deassert(int cpu);
 void mvebu_pmsu_set_cpu_boot_addr(int hw_cpu, void *boot_addr);
+void mvebu_system_controller_set_cpu_boot_addr(void *boot_addr);
 
 void armada_xp_cpu_die(unsigned int cpu);
 

arch/arm/mach-mvebu/system-controller.c

@@ -37,6 +37,8 @@ struct mvebu_system_controller {
 
 	u32 rstoutn_mask_reset_out_en;
 	u32 system_soft_reset;
+
+	u32 resume_boot_addr;
 };
 static struct mvebu_system_controller *mvebu_sc;
 
@@ -52,6 +54,7 @@ static const struct mvebu_system_controller armada_375_system_controller = {
 	.system_soft_reset_offset = 0x58,
 	.rstoutn_mask_reset_out_en = 0x1,
 	.system_soft_reset = 0x1,
+	.resume_boot_addr = 0xd4,
 };
 
 static const struct mvebu_system_controller orion_system_controller = {
@@ -98,6 +101,16 @@ void mvebu_restart(enum reboot_mode mode, const char *cmd)
 		;
 }
 
+#ifdef CONFIG_SMP
+void mvebu_system_controller_set_cpu_boot_addr(void *boot_addr)
+{
+	BUG_ON(system_controller_base == NULL);
+	BUG_ON(mvebu_sc->resume_boot_addr == 0);
+	writel(virt_to_phys(boot_addr), system_controller_base +
+	       mvebu_sc->resume_boot_addr);
+}
+#endif
+
 static int __init mvebu_system_controller_init(void)
 {
 	const struct of_device_id *match;
@@ -114,4 +127,4 @@ static int __init mvebu_system_controller_init(void)
 	return 0;
 }
 
-arch_initcall(mvebu_system_controller_init);
+early_initcall(mvebu_system_controller_init);