]> git.kernelconcepts.de Git - karo-tx-linux.git/blobdiff - arch/arm/mach-uniphier/platsmp.c
Merge remote-tracking branch 'mfd/for-mfd-next'
[karo-tx-linux.git] / arch / arm / mach-uniphier / platsmp.c
index 4b784f7211350f6971d21b2031890a4a76057624..f0577664611c9a6456c8d371ff80955e2d19e011 100644 (file)
  * GNU General Public License for more details.
  */
 
-#include <linux/sizes.h>
-#include <linux/compiler.h>
+#define pr_fmt(fmt)            "uniphier: " fmt
+
 #include <linux/init.h>
 #include <linux/io.h>
-#include <linux/regmap.h>
-#include <linux/mfd/syscon.h>
+#include <linux/ioport.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/sizes.h>
+#include <asm/cacheflush.h>
+#include <asm/hardware/cache-uniphier.h>
+#include <asm/pgtable.h>
 #include <asm/smp.h>
 #include <asm/smp_scu.h>
 
-static struct regmap *sbcm_regmap;
+/*
+ * The secondary CPUs check this register from the boot ROM for the jump
+ * destination.  After that, it can be reused as a scratch register.
+ */
+#define UNIPHIER_SBC_ROM_BOOT_RSV2     0x1208
 
-static void __init uniphier_smp_prepare_cpus(unsigned int max_cpus)
+static void __iomem *uniphier_smp_rom_boot_rsv2;
+static unsigned int uniphier_smp_max_cpus;
+
+extern char uniphier_smp_trampoline;
+extern char uniphier_smp_trampoline_jump;
+extern char uniphier_smp_trampoline_poll_addr;
+extern char uniphier_smp_trampoline_end;
+
+/*
+ * Copy trampoline code to the tail of the 1st section of the page table used
+ * in the boot ROM.  This area is directly accessible by the secondary CPUs
+ * for all the UniPhier SoCs.
+ */
+static const phys_addr_t uniphier_smp_trampoline_dest_end = SECTION_SIZE;
+static phys_addr_t uniphier_smp_trampoline_dest;
+
+static int __init uniphier_smp_copy_trampoline(phys_addr_t poll_addr)
 {
-       static cpumask_t only_cpu_0 = { CPU_BITS_CPU0 };
-       unsigned long scu_base_phys = 0;
-       void __iomem *scu_base;
+       size_t trmp_size;
+       static void __iomem *trmp_base;
 
-       sbcm_regmap = syscon_regmap_lookup_by_compatible(
-                       "socionext,uniphier-system-bus-controller-misc");
-       if (IS_ERR(sbcm_regmap)) {
-               pr_err("failed to regmap system-bus-controller-misc\n");
-               goto err;
+       if (!uniphier_cache_l2_is_enabled()) {
+               pr_warn("outer cache is needed for SMP, but not enabled\n");
+               return -ENODEV;
        }
 
+       uniphier_cache_l2_set_locked_ways(1);
+
+       outer_flush_all();
+
+       trmp_size = &uniphier_smp_trampoline_end - &uniphier_smp_trampoline;
+       uniphier_smp_trampoline_dest = uniphier_smp_trampoline_dest_end -
+                                                               trmp_size;
+
+       uniphier_cache_l2_touch_range(uniphier_smp_trampoline_dest,
+                                     uniphier_smp_trampoline_dest_end);
+
+       trmp_base = ioremap_cache(uniphier_smp_trampoline_dest, trmp_size);
+       if (!trmp_base) {
+               pr_err("failed to map trampoline destination area\n");
+               return -ENOMEM;
+       }
+
+       memcpy(trmp_base, &uniphier_smp_trampoline, trmp_size);
+
+       writel(virt_to_phys(secondary_startup),
+              trmp_base + (&uniphier_smp_trampoline_jump -
+                           &uniphier_smp_trampoline));
+
+       writel(poll_addr, trmp_base + (&uniphier_smp_trampoline_poll_addr -
+                                      &uniphier_smp_trampoline));
+
+       flush_cache_all();      /* flush out trampoline code to outer cache */
+
+       iounmap(trmp_base);
+
+       return 0;
+}
+
+static int __init uniphier_smp_prepare_trampoline(unsigned int max_cpus)
+{
+       struct device_node *np;
+       struct resource res;
+       phys_addr_t rom_rsv2_phys;
+       int ret;
+
+       np = of_find_compatible_node(NULL, NULL,
+                               "socionext,uniphier-system-bus-controller");
+       ret = of_address_to_resource(np, 1, &res);
+       if (ret) {
+               pr_err("failed to get resource of system-bus-controller\n");
+               return ret;
+       }
+
+       rom_rsv2_phys = res.start + UNIPHIER_SBC_ROM_BOOT_RSV2;
+
+       ret = uniphier_smp_copy_trampoline(rom_rsv2_phys);
+       if (ret)
+               return ret;
+
+       uniphier_smp_rom_boot_rsv2 = ioremap(rom_rsv2_phys, sizeof(SZ_4));
+       if (!uniphier_smp_rom_boot_rsv2) {
+               pr_err("failed to map ROM_BOOT_RSV2 register\n");
+               return -ENOMEM;
+       }
+
+       writel(uniphier_smp_trampoline_dest, uniphier_smp_rom_boot_rsv2);
+       asm("sev"); /* Bring up all secondary CPUs to the trampoline code */
+
+       uniphier_smp_max_cpus = max_cpus;       /* save for later use */
+
+       return 0;
+}
+
+static void __init uniphier_smp_unprepare_trampoline(void)
+{
+       iounmap(uniphier_smp_rom_boot_rsv2);
+
+       if (uniphier_smp_trampoline_dest)
+               outer_inv_range(uniphier_smp_trampoline_dest,
+                               uniphier_smp_trampoline_dest_end);
+
+       uniphier_cache_l2_set_locked_ways(0);
+}
+
+static int __init uniphier_smp_enable_scu(void)
+{
+       unsigned long scu_base_phys = 0;
+       void __iomem *scu_base;
+
        if (scu_a9_has_base())
                scu_base_phys = scu_a9_get_base();
 
        if (!scu_base_phys) {
                pr_err("failed to get scu base\n");
-               goto err;
+               return -ENODEV;
        }
 
        scu_base = ioremap(scu_base_phys, SZ_128);
        if (!scu_base) {
-               pr_err("failed to remap scu base (0x%08lx)\n", scu_base_phys);
-               goto err;
+               pr_err("failed to map scu base\n");
+               return -ENOMEM;
        }
 
        scu_enable(scu_base);
        iounmap(scu_base);
 
+       return 0;
+}
+
+static void __init uniphier_smp_prepare_cpus(unsigned int max_cpus)
+{
+       static cpumask_t only_cpu_0 = { CPU_BITS_CPU0 };
+       int ret;
+
+       ret = uniphier_smp_prepare_trampoline(max_cpus);
+       if (ret)
+               goto err;
+
+       ret = uniphier_smp_enable_scu();
+       if (ret)
+               goto err;
+
        return;
 err:
        pr_warn("disabling SMP\n");
        init_cpu_present(&only_cpu_0);
-       sbcm_regmap = NULL;
+       uniphier_smp_unprepare_trampoline();
 }
 
-static int uniphier_boot_secondary(unsigned int cpu,
-                                  struct task_struct *idle)
+static int __init uniphier_smp_boot_secondary(unsigned int cpu,
+                                             struct task_struct *idle)
 {
-       int ret;
+       if (WARN_ON_ONCE(!uniphier_smp_rom_boot_rsv2))
+               return -EFAULT;
 
-       if (!sbcm_regmap)
-               return -ENODEV;
+       writel(cpu, uniphier_smp_rom_boot_rsv2);
+       readl(uniphier_smp_rom_boot_rsv2); /* relax */
 
-       ret = regmap_write(sbcm_regmap, 0x1208,
-                          virt_to_phys(secondary_startup));
-       if (!ret)
-               asm("sev"); /* wake up secondary CPU */
+       asm("sev"); /* wake up secondary CPUs sleeping in the trampoline */
+
+       if (cpu == uniphier_smp_max_cpus - 1) {
+               /* clean up resources if this is the last CPU */
+               uniphier_smp_unprepare_trampoline();
+       }
 
-       return ret;
+       return 0;
 }
 
-struct smp_operations uniphier_smp_ops __initdata = {
+static struct smp_operations uniphier_smp_ops __initdata = {
        .smp_prepare_cpus       = uniphier_smp_prepare_cpus,
-       .smp_boot_secondary     = uniphier_boot_secondary,
+       .smp_boot_secondary     = uniphier_smp_boot_secondary,
 };
 CPU_METHOD_OF_DECLARE(uniphier_smp, "socionext,uniphier-smp",
                      &uniphier_smp_ops);