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         struct clk_omap_reg r;
  35
  36         memcpy(&r, &clk->enable_reg, sizeof(r));
  37         r.offset ^= (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         struct clk_omap_reg r;
  49
  50         memcpy(&r, &clk->enable_reg, sizeof(r));
  51
  52         r.offset ^= (CM_AUTOIDLE ^ CM_ICLKEN);
  53
  54         v = ti_clk_ll_ops->clk_readl(&r);
  55         v &= ~(1 << clk->enable_bit);
  56         ti_clk_ll_ops->clk_writel(v, &r);
  57 }
  58
  59 /**
  60  * omap2430_clk_i2chs_find_idlest - return CM_IDLEST info for 2430 I2CHS
  61  * @clk: struct clk * being enabled
  62  * @idlest_reg: void __iomem ** to store CM_IDLEST reg address into
  63  * @idlest_bit: pointer to a u8 to store the CM_IDLEST bit shift into
  64  * @idlest_val: pointer to a u8 to store the CM_IDLEST indicator
  65  *
  66  * OMAP2430 I2CHS CM_IDLEST bits are in CM_IDLEST1_CORE, but the
  67  * CM_*CLKEN bits are in CM_{I,F}CLKEN2_CORE.  This custom function
  68  * passes back the correct CM_IDLEST register address for I2CHS
  69  * modules.  No return value.
  70  */
  71 static void omap2430_clk_i2chs_find_idlest(struct clk_hw_omap *clk,
  72                                            struct clk_omap_reg *idlest_reg,
  73                                            u8 *idlest_bit,
  74                                            u8 *idlest_val)
  75 {
  76         memcpy(idlest_reg, &clk->enable_reg, sizeof(*idlest_reg));
  77         idlest_reg->offset ^= (OMAP24XX_CM_FCLKEN2 ^ CM_IDLEST);
  78         *idlest_bit = clk->enable_bit;
  79         *idlest_val = OMAP24XX_CM_IDLEST_VAL;
  80 }
  81
  82 /* Public data */
  83
  84 const struct clk_hw_omap_ops clkhwops_iclk = {
  85         .allow_idle     = omap2_clkt_iclk_allow_idle,
  86         .deny_idle      = omap2_clkt_iclk_deny_idle,
  87 };
  88
  89 const struct clk_hw_omap_ops clkhwops_iclk_wait = {
  90         .allow_idle     = omap2_clkt_iclk_allow_idle,
  91         .deny_idle      = omap2_clkt_iclk_deny_idle,
  92         .find_idlest    = omap2_clk_dflt_find_idlest,
  93         .find_companion = omap2_clk_dflt_find_companion,
  94 };
  95
  96 /* 2430 I2CHS has non-standard IDLEST register */
  97 const struct clk_hw_omap_ops clkhwops_omap2430_i2chs_wait = {
  98         .find_idlest    = omap2430_clk_i2chs_find_idlest,
  99         .find_companion = omap2_clk_dflt_find_companion,
 100 };