drivers/clk/at91/clk-utmi.c

   1 /*
   2  * Copyright (C) 2016 Atmel Corporation
   3  *               Wenyou.Yang <wenyou.yang@atmel.com>
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #include <common.h>
   9 #include <clk-uclass.h>
  10 #include <dm/device.h>
  11 #include <linux/io.h>
  12 #include <mach/at91_pmc.h>
  13 #include "pmc.h"
  14
  15 DECLARE_GLOBAL_DATA_PTR;
  16
  17 #define UTMI_FIXED_MUL          40
  18
  19 static int utmi_clk_enable(struct clk *clk)
  20 {
  21         struct pmc_platdata *plat = dev_get_platdata(clk->dev);
  22         struct at91_pmc *pmc = plat->reg_base;
  23         u32 tmp;
  24
  25         if (readl(&pmc->sr) & AT91_PMC_LOCKU)
  26                 return 0;
  27
  28         tmp = readl(&pmc->uckr);
  29         tmp |= AT91_PMC_UPLLEN |
  30                AT91_PMC_UPLLCOUNT |
  31                AT91_PMC_BIASEN;
  32         writel(tmp, &pmc->uckr);
  33
  34         while (!(readl(&pmc->sr) & AT91_PMC_LOCKU))
  35                 ;
  36
  37         return 0;
  38 }
  39
  40 static ulong utmi_clk_get_rate(struct clk *clk)
  41 {
  42         return gd->arch.main_clk_rate_hz * UTMI_FIXED_MUL;
  43 }
  44
  45 static struct clk_ops utmi_clk_ops = {
  46         .enable = utmi_clk_enable,
  47         .get_rate = utmi_clk_get_rate,
  48 };
  49
  50 static int utmi_clk_probe(struct udevice *dev)
  51 {
  52         return at91_pmc_core_probe(dev);
  53 }
  54
  55 static const struct udevice_id utmi_clk_match[] = {
  56         { .compatible = "atmel,at91sam9x5-clk-utmi" },
  57         {}
  58 };
  59
  60 U_BOOT_DRIVER(at91sam9x5_utmi_clk) = {
  61         .name = "at91sam9x5-utmi-clk",
  62         .id = UCLASS_CLK,
  63         .of_match = utmi_clk_match,
  64         .probe = utmi_clk_probe,
  65         .platdata_auto_alloc_size = sizeof(struct pmc_platdata),
  66         .ops = &utmi_clk_ops,
  67 };