linux-imx

/*

 * Nomadik clock implementation

 * Copyright (C) 2013 ST-Ericsson AB

 * License terms: GNU General Public License (GPL) version 2

 * Author: Linus Walleij <linus.walleij@linaro.org>

 */

​

#define pr_fmt(fmt) "Nomadik SRC clocks: " fmt

​

#include <linux/bitops.h>

#include <linux/slab.h>

#include <linux/err.h>

#include <linux/io.h>

#include <linux/clk-provider.h>

#include <linux/of.h>

#include <linux/of_address.h>

#include <linux/debugfs.h>

#include <linux/seq_file.h>

#include <linux/spinlock.h>

#include <linux/reboot.h>

​

/*

 * The Nomadik clock tree is described in the STN8815A12 DB V4.2

 * reference manual for the chip, page 94 ff.

 * Clock IDs are in the STn8815 Reference Manual table 3, page 27.

 */

​

#define SRC_CR          0x00U

#define SRC_CR_T0_ENSEL     BIT(15)

#define SRC_CR_T1_ENSEL     BIT(17)

#define SRC_CR_T2_ENSEL     BIT(19)

#define SRC_CR_T3_ENSEL     BIT(21)

#define SRC_CR_T4_ENSEL     BIT(23)

#define SRC_CR_T5_ENSEL     BIT(25)

#define SRC_CR_T6_ENSEL     BIT(27)

#define SRC_CR_T7_ENSEL     BIT(29)

#define SRC_XTALCR      0x0CU

#define SRC_XTALCR_XTALTIMEN    BIT(20)

#define SRC_XTALCR_SXTALDIS BIT(19)

#define SRC_XTALCR_MXTALSTAT    BIT(2)

#define SRC_XTALCR_MXTALEN  BIT(1)

#define SRC_XTALCR_MXTALOVER    BIT(0)

#define SRC_PLLCR       0x10U

#define SRC_PLLCR_PLLTIMEN  BIT(29)

#define SRC_PLLCR_PLL2EN    BIT(28)

#define SRC_PLLCR_PLL1STAT  BIT(2)

#define SRC_PLLCR_PLL1EN    BIT(1)

#define SRC_PLLCR_PLL1OVER  BIT(0)

#define SRC_PLLFR       0x14U

#define SRC_PCKEN0      0x24U

#define SRC_PCKDIS0     0x28U

#define SRC_PCKENSR0        0x2CU

#define SRC_PCKSR0      0x30U

#define SRC_PCKEN1      0x34U

#define SRC_PCKDIS1     0x38U

#define SRC_PCKENSR1        0x3CU

#define SRC_PCKSR1      0x40U

​

/* Lock protecting the SRC_CR register */

static DEFINE_SPINLOCK(src_lock);

/* Base address of the SRC */

static void __iomem *src_base;

​

static int nomadik_clk_reboot_handler(struct notifier_block *this,

                unsigned long code,

                void *unused)

{

    u32 val;

​

    /* The main chrystal need to be enabled for reboot to work */

    val = readl(src_base + SRC_XTALCR);

    val &= ~SRC_XTALCR_MXTALOVER;

    val |= SRC_XTALCR_MXTALEN;

    pr_crit("force-enabling MXTALO\n");

    writel(val, src_base + SRC_XTALCR);

    return NOTIFY_OK;

}

​

static struct notifier_block nomadik_clk_reboot_notifier = {

    .notifier_call = nomadik_clk_reboot_handler,

};

​

static const struct of_device_id nomadik_src_match[] __initconst = {

    { .compatible = "stericsson,nomadik-src" },

    { /* sentinel */ }

};

​

static void __init nomadik_src_init(void)

{

    struct device_node *np;

    u32 val;

​