drivers/clk/ti/clkt_iclk.c

   1 /*
   2  * OMAP2/3 interface clock control
   3  *
   4  * Copyright (C) 2011 Nokia Corporation
   5  * Paul Walmsley
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11 #undef DEBUG
  12
  13 #include <linux/kernel.h>
  14 #include <linux/clk-provider.h>
  15 #include <linux/io.h>
  16 #include <linux/clk/ti.h>
  17
  18 #include "clock.h"
  19
  20 /* Register offsets */
  21 #define OMAP24XX_CM_FCLKEN2             0x04
  22 #define CM_AUTOIDLE                     0x30
  23 #define CM_ICLKEN                       0x10
  24 #define CM_IDLEST                       0x20
  25
  26 #define OMAP24XX_CM_IDLEST_VAL          0
  27
  28 /* Private functions */
  29
  30 /* XXX */
  31 void omap2_clkt_iclk_allow_idle(struct clk_hw_omap *clk)
  32 {
  33         u32 v;
  34         void __iomem *r;
  35
  36         r = (__force void __iomem *)
  37                 ((__force u32)clk->enable_reg ^ (CM_AUTOIDLE ^ CM_ICLKEN));
  38
  39         v = ti_clk_ll_ops->clk_readl(r);
  40         v |= (1 << clk->enable_bit);
  41         ti_clk_ll_ops->clk_writel(v, r);
  42 }
  43
  44 /* XXX */
  45 void omap2_clkt_iclk_deny_idle(struct clk_hw_omap *clk)
  46 {
  47         u32 v;
  48         void __iomem *r;
  49
  50         r = (__force void __iomem *)
  51                 ((__force u32)clk->enable_reg ^ (CM_AUTOIDLE ^ CM_ICLKEN));
  52
  53         v = ti_clk_ll_ops->clk_readl(r);
  54         v &= ~(1 << clk->enable_bit);
  55         ti_clk_ll_ops->clk_writel(v, r);
  56 }
  57
  58 /**
  59  * omap2430_clk_i2chs_find_idlest - return CM_IDLEST info for 2430 I2CHS
  60  * @clk: struct clk * being enabled
  61  * @idlest_reg: void __iomem ** to store CM_IDLEST reg address into
  62  * @idlest_bit: pointer to a u8 to store the CM_IDLEST bit shift into
  63  * @idlest_val: pointer to a u8 to store the CM_IDLEST indicator
  64  *
  65  * OMAP2430 I2CHS CM_IDLEST bits are in CM_IDLEST1_CORE, but the
  66  * CM_*CLKEN bits are in CM_{I,F}CLKEN2_CORE.  This custom function
  67  * passes back the correct CM_IDLEST register address for I2CHS
  68  * modules.  No return value.
  69  */
  70 static void omap2430_clk_i2chs_find_idlest(struct clk_hw_omap *clk,
  71                                            void __iomem **idlest_reg,
  72                                            u8 *idlest_bit,
  73                                            u8 *idlest_val)
  74 {
  75         u32 r;
  76
  77         r = ((__force u32)clk->enable_reg ^ (OMAP24XX_CM_FCLKEN2 ^ CM_IDLEST));
  78         *idlest_reg = (__force void __iomem *)r;
  79         *idlest_bit = clk->enable_bit;
  80         *idlest_val = OMAP24XX_CM_IDLEST_VAL;
  81 }
  82
  83 /* Public data */
  84
  85 const struct clk_hw_omap_ops clkhwops_iclk = {
  86         .allow_idle     = omap2_clkt_iclk_allow_idle,
  87         .deny_idle      = omap2_clkt_iclk_deny_idle,
  88 };
  89
  90 const struct clk_hw_omap_ops clkhwops_iclk_wait = {
  91         .allow_idle     = omap2_clkt_iclk_allow_idle,
  92         .deny_idle      = omap2_clkt_iclk_deny_idle,
  93         .find_idlest    = omap2_clk_dflt_find_idlest,
  94         .find_companion = omap2_clk_dflt_find_companion,
  95 };
  96
  97 /* 2430 I2CHS has non-standard IDLEST register */
  98 const struct clk_hw_omap_ops clkhwops_omap2430_i2chs_wait = {
  99         .find_idlest    = omap2430_clk_i2chs_find_idlest,
 100         .find_companion = omap2_clk_dflt_find_companion,
 101 };