arch/arm/mach-mvebu/pmsu.c

   1 /*
   2  * Power Management Service Unit(PMSU) support for Armada 370/XP platforms.
   3  *
   4  * Copyright (C) 2012 Marvell
   5  *
   6  * Yehuda Yitschak <yehuday@marvell.com>
   7  * Gregory Clement <gregory.clement@free-electrons.com>
   8  * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
   9  *
  10  * This file is licensed under the terms of the GNU General Public
  11  * License version 2.  This program is licensed "as is" without any
  12  * warranty of any kind, whether express or implied.
  13  *
  14  * The Armada 370 and Armada XP SOCs have a power management service
  15  * unit which is responsible for powering down and waking up CPUs and
  16  * other SOC units
  17  */
  18
  19 #define pr_fmt(fmt) "mvebu-pmsu: " fmt
  20
  21 #include <linux/kernel.h>
  22 #include <linux/init.h>
  23 #include <linux/of_address.h>
  24 #include <linux/io.h>
  25 #include <linux/smp.h>
  26 #include <linux/resource.h>
  27 #include <asm/smp_plat.h>
  28 #include "common.h"
  29 #include "pmsu.h"
  30
  31 static void __iomem *pmsu_mp_base;
  32
  33 #define PMSU_BASE_OFFSET    0x100
  34 #define PMSU_REG_SIZE       0x1000
  35
  36 /* PMSU MP registers */
  37 #define PMSU_BOOT_ADDR_REDIRECT_OFFSET(cpu) ((cpu * 0x100) + 0x124)
  38
  39 /* PMSU fabric registers */
  40 #define L2C_NFABRIC_PM_CTL                  0x4
  41 #define L2C_NFABRIC_PM_CTL_PWR_DOWN             BIT(20)
  42
  43 static struct of_device_id of_pmsu_table[] = {
  44         { .compatible = "marvell,armada-370-pmsu", },
  45         { .compatible = "marvell,armada-370-xp-pmsu", },
  46         { .compatible = "marvell,armada-380-pmsu", },
  47         { /* end of list */ },
  48 };
  49
  50 void mvebu_pmsu_set_cpu_boot_addr(int hw_cpu, void *boot_addr)
  51 {
  52         writel(virt_to_phys(boot_addr), pmsu_mp_base +
  53                 PMSU_BOOT_ADDR_REDIRECT_OFFSET(hw_cpu));
  54 }
  55
  56 static int __init armada_370_xp_pmsu_init(void)
  57 {
  58         struct device_node *np;
  59         struct resource res;
  60         int ret = 0;
  61
  62         np = of_find_matching_node(NULL, of_pmsu_table);
  63         if (!np)
  64                 return 0;
  65
  66         pr_info("Initializing Power Management Service Unit\n");
  67
  68         if (of_address_to_resource(np, 0, &res)) {
  69                 pr_err("unable to get resource\n");
  70                 ret = -ENOENT;
  71                 goto out;
  72         }
  73
  74         if (of_device_is_compatible(np, "marvell,armada-370-xp-pmsu")) {
  75                 pr_warn(FW_WARN "deprecated pmsu binding\n");
  76                 res.start = res.start - PMSU_BASE_OFFSET;
  77                 res.end = res.start + PMSU_REG_SIZE - 1;
  78         }
  79
  80         if (!request_mem_region(res.start, resource_size(&res),
  81                                 np->full_name)) {
  82                 pr_err("unable to request region\n");
  83                 ret = -EBUSY;
  84                 goto out;
  85         }
  86
  87         pmsu_mp_base = ioremap(res.start, resource_size(&res));
  88         if (!pmsu_mp_base) {
  89                 pr_err("unable to map registers\n");
  90                 release_mem_region(res.start, resource_size(&res));
  91                 ret = -ENOMEM;
  92                 goto out;
  93         }
  94
  95  out:
  96         of_node_put(np);
  97         return ret;
  98 }
  99
 100 static void armada_370_xp_pmsu_enable_l2_powerdown_onidle(void)
 101 {
 102         u32 reg;
 103
 104         if (pmsu_mp_base == NULL)
 105                 return;
 106
 107         /* Enable L2 & Fabric powerdown in Deep-Idle mode - Fabric */
 108         reg = readl(pmsu_mp_base + L2C_NFABRIC_PM_CTL);
 109         reg |= L2C_NFABRIC_PM_CTL_PWR_DOWN;
 110         writel(reg, pmsu_mp_base + L2C_NFABRIC_PM_CTL);
 111 }
 112
 113 early_initcall(armada_370_xp_pmsu_init);