diff options
Diffstat (limited to '')
-rw-r--r-- | drivers/clk/rockchip/clk-ddr.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/drivers/clk/rockchip/clk-ddr.c b/drivers/clk/rockchip/clk-ddr.c new file mode 100644 index 000000000..ebce52600 --- /dev/null +++ b/drivers/clk/rockchip/clk-ddr.c @@ -0,0 +1,147 @@ +/* + * Copyright (c) 2016 Rockchip Electronics Co. Ltd. + * Author: Lin Huang <hl@rock-chips.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/arm-smccc.h> +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/io.h> +#include <linux/slab.h> +#include <soc/rockchip/rockchip_sip.h> +#include "clk.h" + +struct rockchip_ddrclk { + struct clk_hw hw; + void __iomem *reg_base; + int mux_offset; + int mux_shift; + int mux_width; + int div_shift; + int div_width; + int ddr_flag; + spinlock_t *lock; +}; + +#define to_rockchip_ddrclk_hw(hw) container_of(hw, struct rockchip_ddrclk, hw) + +static int rockchip_ddrclk_sip_set_rate(struct clk_hw *hw, unsigned long drate, + unsigned long prate) +{ + struct rockchip_ddrclk *ddrclk = to_rockchip_ddrclk_hw(hw); + unsigned long flags; + struct arm_smccc_res res; + + spin_lock_irqsave(ddrclk->lock, flags); + arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, drate, 0, + ROCKCHIP_SIP_CONFIG_DRAM_SET_RATE, + 0, 0, 0, 0, &res); + spin_unlock_irqrestore(ddrclk->lock, flags); + + return res.a0; +} + +static unsigned long +rockchip_ddrclk_sip_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct arm_smccc_res res; + + arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, 0, 0, + ROCKCHIP_SIP_CONFIG_DRAM_GET_RATE, + 0, 0, 0, 0, &res); + + return res.a0; +} + +static long rockchip_ddrclk_sip_round_rate(struct clk_hw *hw, + unsigned long rate, + unsigned long *prate) +{ + struct arm_smccc_res res; + + arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, rate, 0, + ROCKCHIP_SIP_CONFIG_DRAM_ROUND_RATE, + 0, 0, 0, 0, &res); + + return res.a0; +} + +static u8 rockchip_ddrclk_get_parent(struct clk_hw *hw) +{ + struct rockchip_ddrclk *ddrclk = to_rockchip_ddrclk_hw(hw); + u32 val; + + val = clk_readl(ddrclk->reg_base + + ddrclk->mux_offset) >> ddrclk->mux_shift; + val &= GENMASK(ddrclk->mux_width - 1, 0); + + return val; +} + +static const struct clk_ops rockchip_ddrclk_sip_ops = { + .recalc_rate = rockchip_ddrclk_sip_recalc_rate, + .set_rate = rockchip_ddrclk_sip_set_rate, + .round_rate = rockchip_ddrclk_sip_round_rate, + .get_parent = rockchip_ddrclk_get_parent, +}; + +struct clk *rockchip_clk_register_ddrclk(const char *name, int flags, + const char *const *parent_names, + u8 num_parents, int mux_offset, + int mux_shift, int mux_width, + int div_shift, int div_width, + int ddr_flag, void __iomem *reg_base, + spinlock_t *lock) +{ + struct rockchip_ddrclk *ddrclk; + struct clk_init_data init; + struct clk *clk; + + ddrclk = kzalloc(sizeof(*ddrclk), GFP_KERNEL); + if (!ddrclk) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.parent_names = parent_names; + init.num_parents = num_parents; + + init.flags = flags; + init.flags |= CLK_SET_RATE_NO_REPARENT; + + switch (ddr_flag) { + case ROCKCHIP_DDRCLK_SIP: + init.ops = &rockchip_ddrclk_sip_ops; + break; + default: + pr_err("%s: unsupported ddrclk type %d\n", __func__, ddr_flag); + kfree(ddrclk); + return ERR_PTR(-EINVAL); + } + + ddrclk->reg_base = reg_base; + ddrclk->lock = lock; + ddrclk->hw.init = &init; + ddrclk->mux_offset = mux_offset; + ddrclk->mux_shift = mux_shift; + ddrclk->mux_width = mux_width; + ddrclk->div_shift = div_shift; + ddrclk->div_width = div_width; + ddrclk->ddr_flag = ddr_flag; + + clk = clk_register(NULL, &ddrclk->hw); + if (IS_ERR(clk)) + kfree(ddrclk); + + return clk; +} |