git.sur5r.net Git - u-boot/blob - drivers/clk/at91/clk-h32mx.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2016 Atmel Corporation
   4  *               Wenyou.Yang <wenyou.yang@atmel.com>
   5  */
   6
   7 #include <common.h>
   8 #include <clk-uclass.h>
   9 #include <dm.h>
  10 #include <dm/util.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 H32MX_MAX_FREQ  90000000
  18
  19 static ulong sama5d4_h32mx_clk_get_rate(struct clk *clk)
  20 {
  21         struct pmc_platdata *plat = dev_get_platdata(clk->dev);
  22         struct at91_pmc *pmc = plat->reg_base;
  23         ulong rate = gd->arch.mck_rate_hz;
  24
  25         if (readl(&pmc->mckr) & AT91_PMC_MCKR_H32MXDIV)
  26                 rate /= 2;
  27
  28         if (rate > H32MX_MAX_FREQ)
  29                 dm_warn("H32MX clock is too fast\n");
  30
  31         return rate;
  32 }
  33
  34 static struct clk_ops sama5d4_h32mx_clk_ops = {
  35         .get_rate = sama5d4_h32mx_clk_get_rate,
  36 };
  37
  38 static int sama5d4_h32mx_clk_probe(struct udevice *dev)
  39 {
  40         return at91_pmc_core_probe(dev);
  41 }
  42
  43 static const struct udevice_id sama5d4_h32mx_clk_match[] = {
  44         { .compatible = "atmel,sama5d4-clk-h32mx" },
  45         {}
  46 };
  47
  48 U_BOOT_DRIVER(sama5d4_h32mx_clk) = {
  49         .name = "sama5d4-h32mx-clk",
  50         .id = UCLASS_CLK,
  51         .of_match = sama5d4_h32mx_clk_match,
  52         .probe = sama5d4_h32mx_clk_probe,
  53         .platdata_auto_alloc_size = sizeof(struct pmc_platdata),
  54         .ops = &sama5d4_h32mx_clk_ops,
  55 };