arch/arm/mach-aspeed/ast2500/clk_ast2500.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2016 Google, Inc
   4  */
   5
   6 #include <common.h>
   7 #include <dm.h>
   8 #include <asm/io.h>
   9 #include <asm/arch/scu_ast2500.h>
  10
  11 int ast_get_clk(struct udevice **devp)
  12 {
  13         return uclass_get_device_by_driver(UCLASS_CLK,
  14                         DM_GET_DRIVER(aspeed_ast2500_scu), devp);
  15 }
  16
  17 void *ast_get_scu(void)
  18 {
  19         struct ast2500_clk_priv *priv;
  20         struct udevice *dev;
  21         int ret;
  22
  23         ret = ast_get_clk(&dev);
  24         if (ret)
  25                 return ERR_PTR(ret);
  26
  27         priv = dev_get_priv(dev);
  28
  29         return priv->scu;
  30 }
  31
  32 void ast_scu_unlock(struct ast2500_scu *scu)
  33 {
  34         writel(SCU_UNLOCK_VALUE, &scu->protection_key);
  35         while (!readl(&scu->protection_key))
  36                 ;
  37 }
  38
  39 void ast_scu_lock(struct ast2500_scu *scu)
  40 {
  41         writel(~SCU_UNLOCK_VALUE, &scu->protection_key);
  42         while (readl(&scu->protection_key))
  43                 ;
  44 }