ARM: imx: Add Freescale LS1021A SMP support

Freescale LS1021A SoCs deploy two cortex-A7 processors,
this adds bring-up support for the secondary core.
Signed-off-by: Jingchang Lu <b35083@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

arch/arm/mach-imx/Makefile

@@ -89,7 +89,7 @@ obj-$(CONFIG_HAVE_IMX_ANATOP) += anatop.o
 obj-$(CONFIG_HAVE_IMX_GPC) += gpc.o
 obj-$(CONFIG_HAVE_IMX_MMDC) += mmdc.o
 obj-$(CONFIG_HAVE_IMX_SRC) += src.o
-ifdef CONFIG_SOC_IMX6
+ifneq ($(CONFIG_SOC_IMX6)$(CONFIG_SOC_LS1021A),)
 AFLAGS_headsmp.o :=-Wa,-march=armv7-a
 obj-$(CONFIG_SMP) += headsmp.o platsmp.o
 obj-$(CONFIG_HOTPLUG_CPU) += hotplug.o

arch/arm/mach-imx/common.h

@@ -158,5 +158,6 @@ static inline void imx_init_l2cache(void) {}
 #endif
 
 extern struct smp_operations imx_smp_ops;
+extern struct smp_operations ls1021a_smp_ops;
 
 #endif

arch/arm/mach-imx/mach-ls1021a.c

@@ -17,5 +17,6 @@ static const char * const ls1021a_dt_compat[] __initconst = {
 };
 
 DT_MACHINE_START(LS1021A, "Freescale LS1021A")
+	.smp		= smp_ops(ls1021a_smp_ops),
 	.dt_compat	= ls1021a_dt_compat,
 MACHINE_END

arch/arm/mach-imx/platsmp.c

@@ -11,7 +11,10 @@
  */
 
 #include <linux/init.h>
+#include <linux/of_address.h>
+#include <linux/of.h>
 #include <linux/smp.h>
+
 #include <asm/cacheflush.h>
 #include <asm/page.h>
 #include <asm/smp_scu.h>
@@ -94,3 +97,33 @@ struct smp_operations  imx_smp_ops __initdata = {
 	.cpu_kill		= imx_cpu_kill,
 #endif
 };
+
+#define DCFG_CCSR_SCRATCHRW1	0x200
+
+static int ls1021a_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+	arch_send_wakeup_ipi_mask(cpumask_of(cpu));
+
+	return 0;
+}
+
+static void __init ls1021a_smp_prepare_cpus(unsigned int max_cpus)
+{
+	struct device_node *np;
+	void __iomem *dcfg_base;
+	unsigned long paddr;
+
+	np = of_find_compatible_node(NULL, NULL, "fsl,ls1021a-dcfg");
+	dcfg_base = of_iomap(np, 0);
+	BUG_ON(!dcfg_base);
+
+	paddr = virt_to_phys(secondary_startup);
+	writel_relaxed(cpu_to_be32(paddr), dcfg_base + DCFG_CCSR_SCRATCHRW1);
+
+	iounmap(dcfg_base);
+}
+
+struct smp_operations  ls1021a_smp_ops __initdata = {
+	.smp_prepare_cpus	= ls1021a_smp_prepare_cpus,
+	.smp_boot_secondary	= ls1021a_boot_secondary,
+};