arch/arm/mach-ux500/cpu-db8500.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2008-2009 ST-Ericsson SA
   4  *
   5  * Author: Srinidhi KASAGAR <srinidhi.kasagar@stericsson.com>
   6  */
   7 #include <linux/types.h>
   8 #include <linux/init.h>
   9 #include <linux/device.h>
  10 #include <linux/amba/bus.h>
  11 #include <linux/interrupt.h>
  12 #include <linux/irq.h>
  13 #include <linux/irqchip.h>
  14 #include <linux/irqchip/arm-gic.h>
  15 #include <linux/mfd/dbx500-prcmu.h>
  16 #include <linux/platform_data/arm-ux500-pm.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/io.h>
  19 #include <linux/of.h>
  20 #include <linux/of_address.h>
  21 #include <linux/of_platform.h>
  22 #include <linux/regulator/machine.h>
  23
  24 #include <asm/outercache.h>
  25 #include <asm/hardware/cache-l2x0.h>
  26 #include <asm/mach/map.h>
  27 #include <asm/mach/arch.h>
  28
  29 #include "db8500-regs.h"
  30 #include "pm_domains.h"
  31
  32 static int __init ux500_l2x0_unlock(void)
  33 {
  34         int i;
  35         struct device_node *np;
  36         void __iomem *l2x0_base;
  37
  38         np = of_find_compatible_node(NULL, NULL, "arm,pl310-cache");
  39         l2x0_base = of_iomap(np, 0);
  40         of_node_put(np);
  41         if (!l2x0_base)
  42                 return -ENODEV;
  43
  44         /*
  45          * Unlock Data and Instruction Lock if locked. Ux500 U-Boot versions
  46          * apparently locks both caches before jumping to the kernel. The
  47          * l2x0 core will not touch the unlock registers if the l2x0 is
  48          * already enabled, so we do it right here instead. The PL310 has
  49          * 8 sets of registers, one per possible CPU.
  50          */
  51         for (i = 0; i < 8; i++) {
  52                 writel_relaxed(0x0, l2x0_base + L2X0_LOCKDOWN_WAY_D_BASE +
  53                                i * L2X0_LOCKDOWN_STRIDE);
  54                 writel_relaxed(0x0, l2x0_base + L2X0_LOCKDOWN_WAY_I_BASE +
  55                                i * L2X0_LOCKDOWN_STRIDE);
  56         }
  57         iounmap(l2x0_base);
  58         return 0;
  59 }
  60
  61 static void ux500_l2c310_write_sec(unsigned long val, unsigned reg)
  62 {
  63         /*
  64          * We can't write to secure registers as we are in non-secure
  65          * mode, until we have some SMI service available.
  66          */
  67 }
  68
  69 /*
  70  * FIXME: Should we set up the GPIO domain here?
  71  *
  72  * The problem is that we cannot put the interrupt resources into the platform
  73  * device until the irqdomain has been added. Right now, we set the GIC interrupt
  74  * domain from init_irq(), then load the gpio driver from
  75  * core_initcall(nmk_gpio_init) and add the platform devices from
  76  * arch_initcall(customize_machine).
  77  *
  78  * This feels fragile because it depends on the gpio device getting probed
  79  * _before_ any device uses the gpio interrupts.
  80 */
  81 static void __init ux500_init_irq(void)
  82 {
  83         struct device_node *np;
  84         struct resource r;
  85
  86         irqchip_init();
  87         prcmu_early_init();
  88         np = of_find_compatible_node(NULL, NULL, "stericsson,db8500-prcmu");
  89         of_address_to_resource(np, 0, &r);
  90         of_node_put(np);
  91         if (!r.start) {
  92                 pr_err("could not find PRCMU base resource\n");
  93                 return;
  94         }
  95         ux500_pm_init(r.start, r.end-r.start);
  96
  97         /* Unlock before init */
  98         ux500_l2x0_unlock();
  99         outer_cache.write_sec = ux500_l2c310_write_sec;
 100 }
 101
 102 static void ux500_restart(enum reboot_mode mode, const char *cmd)
 103 {
 104         local_irq_disable();
 105         local_fiq_disable();
 106
 107         prcmu_system_reset(0);
 108 }
 109
 110 static const struct of_device_id u8500_local_bus_nodes[] = {
 111         /* only create devices below soc node */
 112         { .compatible = "stericsson,db8500", },
 113         { .compatible = "simple-bus"},
 114         { },
 115 };
 116
 117 static void __init u8500_init_machine(void)
 118 {
 119         /* Initialize ux500 power domains */
 120         ux500_pm_domains_init();
 121
 122         of_platform_populate(NULL, u8500_local_bus_nodes,
 123                              NULL, NULL);
 124 }
 125
 126 static const char * stericsson_dt_platform_compat[] = {
 127         "st-ericsson,u8500",
 128         "st-ericsson,u9500",
 129         NULL,
 130 };
 131
 132 DT_MACHINE_START(U8500_DT, "ST-Ericsson Ux5x0 platform (Device Tree Support)")
 133         .l2c_aux_val    = 0,
 134         .l2c_aux_mask   = ~0,
 135         .init_irq       = ux500_init_irq,
 136         .init_machine   = u8500_init_machine,
 137         .dt_compat      = stericsson_dt_platform_compat,
 138         .restart        = ux500_restart,
 139 MACHINE_END