drivers/clk/rockchip/clk-ddr.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (c) 2016 Rockchip Electronics Co. Ltd.
   4  * Author: Lin Huang <hl@rock-chips.com>
   5  */
   6
   7 #include <linux/arm-smccc.h>
   8 #include <linux/clk.h>
   9 #include <linux/clk-provider.h>
  10 #include <linux/io.h>
  11 #include <linux/slab.h>
  12 #include <soc/rockchip/rockchip_sip.h>
  13 #include "clk.h"
  14
  15 struct rockchip_ddrclk {
  16         struct clk_hw   hw;
  17         void __iomem    *reg_base;
  18         int             mux_offset;
  19         int             mux_shift;
  20         int             mux_width;
  21         int             div_shift;
  22         int             div_width;
  23         int             ddr_flag;
  24         spinlock_t      *lock;
  25 };
  26
  27 #define to_rockchip_ddrclk_hw(hw) container_of(hw, struct rockchip_ddrclk, hw)
  28
  29 static int rockchip_ddrclk_sip_set_rate(struct clk_hw *hw, unsigned long drate,
  30                                         unsigned long prate)
  31 {
  32         struct rockchip_ddrclk *ddrclk = to_rockchip_ddrclk_hw(hw);
  33         unsigned long flags;
  34         struct arm_smccc_res res;
  35
  36         spin_lock_irqsave(ddrclk->lock, flags);
  37         arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, drate, 0,
  38                       ROCKCHIP_SIP_CONFIG_DRAM_SET_RATE,
  39                       0, 0, 0, 0, &res);
  40         spin_unlock_irqrestore(ddrclk->lock, flags);
  41
  42         return res.a0;
  43 }
  44
  45 static unsigned long
  46 rockchip_ddrclk_sip_recalc_rate(struct clk_hw *hw,
  47                                 unsigned long parent_rate)
  48 {
  49         struct arm_smccc_res res;
  50
  51         arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, 0, 0,
  52                       ROCKCHIP_SIP_CONFIG_DRAM_GET_RATE,
  53                       0, 0, 0, 0, &res);
  54
  55         return res.a0;
  56 }
  57
  58 static long rockchip_ddrclk_sip_round_rate(struct clk_hw *hw,
  59                                            unsigned long rate,
  60                                            unsigned long *prate)
  61 {
  62         struct arm_smccc_res res;
  63
  64         arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, rate, 0,
  65                       ROCKCHIP_SIP_CONFIG_DRAM_ROUND_RATE,
  66                       0, 0, 0, 0, &res);
  67
  68         return res.a0;
  69 }
  70
  71 static u8 rockchip_ddrclk_get_parent(struct clk_hw *hw)
  72 {
  73         struct rockchip_ddrclk *ddrclk = to_rockchip_ddrclk_hw(hw);
  74         u32 val;
  75
  76         val = readl(ddrclk->reg_base +
  77                         ddrclk->mux_offset) >> ddrclk->mux_shift;
  78         val &= GENMASK(ddrclk->mux_width - 1, 0);
  79
  80         return val;
  81 }
  82
  83 static const struct clk_ops rockchip_ddrclk_sip_ops = {
  84         .recalc_rate = rockchip_ddrclk_sip_recalc_rate,
  85         .set_rate = rockchip_ddrclk_sip_set_rate,
  86         .round_rate = rockchip_ddrclk_sip_round_rate,
  87         .get_parent = rockchip_ddrclk_get_parent,
  88 };
  89
  90 struct clk *rockchip_clk_register_ddrclk(const char *name, int flags,
  91                                          const char *const *parent_names,
  92                                          u8 num_parents, int mux_offset,
  93                                          int mux_shift, int mux_width,
  94                                          int div_shift, int div_width,
  95                                          int ddr_flag, void __iomem *reg_base,
  96                                          spinlock_t *lock)
  97 {
  98         struct rockchip_ddrclk *ddrclk;
  99         struct clk_init_data init;
 100         struct clk *clk;
 101
 102         ddrclk = kzalloc(sizeof(*ddrclk), GFP_KERNEL);
 103         if (!ddrclk)
 104                 return ERR_PTR(-ENOMEM);
 105
 106         init.name = name;
 107         init.parent_names = parent_names;
 108         init.num_parents = num_parents;
 109
 110         init.flags = flags;
 111         init.flags |= CLK_SET_RATE_NO_REPARENT;
 112
 113         switch (ddr_flag) {
 114         case ROCKCHIP_DDRCLK_SIP:
 115                 init.ops = &rockchip_ddrclk_sip_ops;
 116                 break;
 117         default:
 118                 pr_err("%s: unsupported ddrclk type %d\n", __func__, ddr_flag);
 119                 kfree(ddrclk);
 120                 return ERR_PTR(-EINVAL);
 121         }
 122
 123         ddrclk->reg_base = reg_base;
 124         ddrclk->lock = lock;
 125         ddrclk->hw.init = &init;
 126         ddrclk->mux_offset = mux_offset;
 127         ddrclk->mux_shift = mux_shift;
 128         ddrclk->mux_width = mux_width;
 129         ddrclk->div_shift = div_shift;
 130         ddrclk->div_width = div_width;
 131         ddrclk->ddr_flag = ddr_flag;
 132
 133         clk = clk_register(NULL, &ddrclk->hw);
 134         if (IS_ERR(clk))
 135                 kfree(ddrclk);
 136
 137         return clk;
 138 }