| /* |
| * Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.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. |
| * |
| */ |
| |
| #include <linux/clk-provider.h> |
| #include <linux/clkdev.h> |
| #include <linux/clk/at91_pmc.h> |
| #include <linux/of.h> |
| #include <linux/of_address.h> |
| #include <linux/io.h> |
| |
| #include "pmc.h" |
| |
| #define PERIPHERAL_MAX 64 |
| |
| #define PERIPHERAL_AT91RM9200 0 |
| #define PERIPHERAL_AT91SAM9X5 1 |
| |
| #define PERIPHERAL_ID_MIN 2 |
| #define PERIPHERAL_ID_MAX 31 |
| #define PERIPHERAL_MASK(id) (1 << ((id) & PERIPHERAL_ID_MAX)) |
| |
| #define PERIPHERAL_RSHIFT_MASK 0x3 |
| #define PERIPHERAL_RSHIFT(val) (((val) >> 16) & PERIPHERAL_RSHIFT_MASK) |
| |
| #define PERIPHERAL_MAX_SHIFT 3 |
| |
| struct clk_peripheral { |
| struct clk_hw hw; |
| struct at91_pmc *pmc; |
| u32 id; |
| }; |
| |
| #define to_clk_peripheral(hw) container_of(hw, struct clk_peripheral, hw) |
| |
| struct clk_sam9x5_peripheral { |
| struct clk_hw hw; |
| struct at91_pmc *pmc; |
| struct clk_range range; |
| u32 id; |
| u32 div; |
| bool auto_div; |
| }; |
| |
| #define to_clk_sam9x5_peripheral(hw) \ |
| container_of(hw, struct clk_sam9x5_peripheral, hw) |
| |
| static int clk_peripheral_enable(struct clk_hw *hw) |
| { |
| struct clk_peripheral *periph = to_clk_peripheral(hw); |
| struct at91_pmc *pmc = periph->pmc; |
| int offset = AT91_PMC_PCER; |
| u32 id = periph->id; |
| |
| if (id < PERIPHERAL_ID_MIN) |
| return 0; |
| if (id > PERIPHERAL_ID_MAX) |
| offset = AT91_PMC_PCER1; |
| pmc_write(pmc, offset, PERIPHERAL_MASK(id)); |
| return 0; |
| } |
| |
| static void clk_peripheral_disable(struct clk_hw *hw) |
| { |
| struct clk_peripheral *periph = to_clk_peripheral(hw); |
| struct at91_pmc *pmc = periph->pmc; |
| int offset = AT91_PMC_PCDR; |
| u32 id = periph->id; |
| |
| if (id < PERIPHERAL_ID_MIN) |
| return; |
| if (id > PERIPHERAL_ID_MAX) |
| offset = AT91_PMC_PCDR1; |
| pmc_write(pmc, offset, PERIPHERAL_MASK(id)); |
| } |
| |
| static int clk_peripheral_is_enabled(struct clk_hw *hw) |
| { |
| struct clk_peripheral *periph = to_clk_peripheral(hw); |
| struct at91_pmc *pmc = periph->pmc; |
| int offset = AT91_PMC_PCSR; |
| u32 id = periph->id; |
| |
| if (id < PERIPHERAL_ID_MIN) |
| return 1; |
| if (id > PERIPHERAL_ID_MAX) |
| offset = AT91_PMC_PCSR1; |
| return !!(pmc_read(pmc, offset) & PERIPHERAL_MASK(id)); |
| } |
| |
| static const struct clk_ops peripheral_ops = { |
| .enable = clk_peripheral_enable, |
| .disable = clk_peripheral_disable, |
| .is_enabled = clk_peripheral_is_enabled, |
| }; |
| |
| static struct clk * __init |
| at91_clk_register_peripheral(struct at91_pmc *pmc, const char *name, |
| const char *parent_name, u32 id) |
| { |
| struct clk_peripheral *periph; |
| struct clk *clk = NULL; |
| struct clk_init_data init; |
| |
| if (!pmc || !name || !parent_name || id > PERIPHERAL_ID_MAX) |
| return ERR_PTR(-EINVAL); |
| |
| periph = kzalloc(sizeof(*periph), GFP_KERNEL); |
| if (!periph) |
| return ERR_PTR(-ENOMEM); |
| |
| init.name = name; |
| init.ops = &peripheral_ops; |
| init.parent_names = (parent_name ? &parent_name : NULL); |
| init.num_parents = (parent_name ? 1 : 0); |
| init.flags = 0; |
| |
| periph->id = id; |
| periph->hw.init = &init; |
| periph->pmc = pmc; |
| |
| clk = clk_register(NULL, &periph->hw); |
| if (IS_ERR(clk)) |
| kfree(periph); |
| |
| return clk; |
| } |
| |
| static void clk_sam9x5_peripheral_autodiv(struct clk_sam9x5_peripheral *periph) |
| { |
| struct clk_hw *parent; |
| unsigned long parent_rate; |
| int shift = 0; |
| |
| if (!periph->auto_div) |
| return; |
| |
| if (periph->range.max) { |
| parent = clk_hw_get_parent_by_index(&periph->hw, 0); |
| parent_rate = clk_hw_get_rate(parent); |
| if (!parent_rate) |
| return; |
| |
| for (; shift < PERIPHERAL_MAX_SHIFT; shift++) { |
| if (parent_rate >> shift <= periph->range.max) |
| break; |
| } |
| } |
| |
| periph->auto_div = false; |
| periph->div = shift; |
| } |
| |
| static int clk_sam9x5_peripheral_enable(struct clk_hw *hw) |
| { |
| struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw); |
| struct at91_pmc *pmc = periph->pmc; |
| u32 tmp; |
| |
| if (periph->id < PERIPHERAL_ID_MIN) |
| return 0; |
| |
| pmc_lock(pmc); |
| pmc_write(pmc, AT91_PMC_PCR, (periph->id & AT91_PMC_PCR_PID_MASK)); |
| tmp = pmc_read(pmc, AT91_PMC_PCR) & ~AT91_PMC_PCR_DIV_MASK; |
| pmc_write(pmc, AT91_PMC_PCR, tmp | AT91_PMC_PCR_DIV(periph->div) |
| | AT91_PMC_PCR_CMD |
| | AT91_PMC_PCR_EN); |
| pmc_unlock(pmc); |
| return 0; |
| } |
| |
| static void clk_sam9x5_peripheral_disable(struct clk_hw *hw) |
| { |
| struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw); |
| struct at91_pmc *pmc = periph->pmc; |
| u32 tmp; |
| |
| if (periph->id < PERIPHERAL_ID_MIN) |
| return; |
| |
| pmc_lock(pmc); |
| pmc_write(pmc, AT91_PMC_PCR, (periph->id & AT91_PMC_PCR_PID_MASK)); |
| tmp = pmc_read(pmc, AT91_PMC_PCR) & ~AT91_PMC_PCR_EN; |
| pmc_write(pmc, AT91_PMC_PCR, tmp | AT91_PMC_PCR_CMD); |
| pmc_unlock(pmc); |
| } |
| |
| static int clk_sam9x5_peripheral_is_enabled(struct clk_hw *hw) |
| { |
| struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw); |
| struct at91_pmc *pmc = periph->pmc; |
| int ret; |
| |
| if (periph->id < PERIPHERAL_ID_MIN) |
| return 1; |
| |
| pmc_lock(pmc); |
| pmc_write(pmc, AT91_PMC_PCR, (periph->id & AT91_PMC_PCR_PID_MASK)); |
| ret = !!(pmc_read(pmc, AT91_PMC_PCR) & AT91_PMC_PCR_EN); |
| pmc_unlock(pmc); |
| |
| return ret; |
| } |
| |
| static unsigned long |
| clk_sam9x5_peripheral_recalc_rate(struct clk_hw *hw, |
| unsigned long parent_rate) |
| { |
| struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw); |
| struct at91_pmc *pmc = periph->pmc; |
| u32 tmp; |
| |
| if (periph->id < PERIPHERAL_ID_MIN) |
| return parent_rate; |
| |
| pmc_lock(pmc); |
| pmc_write(pmc, AT91_PMC_PCR, (periph->id & AT91_PMC_PCR_PID_MASK)); |
| tmp = pmc_read(pmc, AT91_PMC_PCR); |
| pmc_unlock(pmc); |
| |
| if (tmp & AT91_PMC_PCR_EN) { |
| periph->div = PERIPHERAL_RSHIFT(tmp); |
| periph->auto_div = false; |
| } else { |
| clk_sam9x5_peripheral_autodiv(periph); |
| } |
| |
| return parent_rate >> periph->div; |
| } |
| |
| static long clk_sam9x5_peripheral_round_rate(struct clk_hw *hw, |
| unsigned long rate, |
| unsigned long *parent_rate) |
| { |
| int shift = 0; |
| unsigned long best_rate; |
| unsigned long best_diff; |
| unsigned long cur_rate = *parent_rate; |
| unsigned long cur_diff; |
| struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw); |
| |
| if (periph->id < PERIPHERAL_ID_MIN || !periph->range.max) |
| return *parent_rate; |
| |
| if (periph->range.max) { |
| for (; shift <= PERIPHERAL_MAX_SHIFT; shift++) { |
| cur_rate = *parent_rate >> shift; |
| if (cur_rate <= periph->range.max) |
| break; |
| } |
| } |
| |
| if (rate >= cur_rate) |
| return cur_rate; |
| |
| best_diff = cur_rate - rate; |
| best_rate = cur_rate; |
| for (; shift <= PERIPHERAL_MAX_SHIFT; shift++) { |
| cur_rate = *parent_rate >> shift; |
| if (cur_rate < rate) |
| cur_diff = rate - cur_rate; |
| else |
| cur_diff = cur_rate - rate; |
| |
| if (cur_diff < best_diff) { |
| best_diff = cur_diff; |
| best_rate = cur_rate; |
| } |
| |
| if (!best_diff || cur_rate < rate) |
| break; |
| } |
| |
| return best_rate; |
| } |
| |
| static int clk_sam9x5_peripheral_set_rate(struct clk_hw *hw, |
| unsigned long rate, |
| unsigned long parent_rate) |
| { |
| int shift; |
| struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw); |
| if (periph->id < PERIPHERAL_ID_MIN || !periph->range.max) { |
| if (parent_rate == rate) |
| return 0; |
| else |
| return -EINVAL; |
| } |
| |
| if (periph->range.max && rate > periph->range.max) |
| return -EINVAL; |
| |
| for (shift = 0; shift <= PERIPHERAL_MAX_SHIFT; shift++) { |
| if (parent_rate >> shift == rate) { |
| periph->auto_div = false; |
| periph->div = shift; |
| return 0; |
| } |
| } |
| |
| return -EINVAL; |
| } |
| |
| static const struct clk_ops sam9x5_peripheral_ops = { |
| .enable = clk_sam9x5_peripheral_enable, |
| .disable = clk_sam9x5_peripheral_disable, |
| .is_enabled = clk_sam9x5_peripheral_is_enabled, |
| .recalc_rate = clk_sam9x5_peripheral_recalc_rate, |
| .round_rate = clk_sam9x5_peripheral_round_rate, |
| .set_rate = clk_sam9x5_peripheral_set_rate, |
| }; |
| |
| static struct clk * __init |
| at91_clk_register_sam9x5_peripheral(struct at91_pmc *pmc, const char *name, |
| const char *parent_name, u32 id, |
| const struct clk_range *range) |
| { |
| struct clk_sam9x5_peripheral *periph; |
| struct clk *clk = NULL; |
| struct clk_init_data init; |
| |
| if (!pmc || !name || !parent_name) |
| return ERR_PTR(-EINVAL); |
| |
| periph = kzalloc(sizeof(*periph), GFP_KERNEL); |
| if (!periph) |
| return ERR_PTR(-ENOMEM); |
| |
| init.name = name; |
| init.ops = &sam9x5_peripheral_ops; |
| init.parent_names = (parent_name ? &parent_name : NULL); |
| init.num_parents = (parent_name ? 1 : 0); |
| init.flags = 0; |
| |
| periph->id = id; |
| periph->hw.init = &init; |
| periph->div = 0; |
| periph->pmc = pmc; |
| periph->auto_div = true; |
| periph->range = *range; |
| |
| clk = clk_register(NULL, &periph->hw); |
| if (IS_ERR(clk)) |
| kfree(periph); |
| else |
| clk_sam9x5_peripheral_autodiv(periph); |
| |
| return clk; |
| } |
| |
| static void __init |
| of_at91_clk_periph_setup(struct device_node *np, struct at91_pmc *pmc, u8 type) |
| { |
| int num; |
| u32 id; |
| struct clk *clk; |
| const char *parent_name; |
| const char *name; |
| struct device_node *periphclknp; |
| |
| parent_name = of_clk_get_parent_name(np, 0); |
| if (!parent_name) |
| return; |
| |
| num = of_get_child_count(np); |
| if (!num || num > PERIPHERAL_MAX) |
| return; |
| |
| for_each_child_of_node(np, periphclknp) { |
| if (of_property_read_u32(periphclknp, "reg", &id)) |
| continue; |
| |
| if (id >= PERIPHERAL_MAX) |
| continue; |
| |
| if (of_property_read_string(np, "clock-output-names", &name)) |
| name = periphclknp->name; |
| |
| if (type == PERIPHERAL_AT91RM9200) { |
| clk = at91_clk_register_peripheral(pmc, name, |
| parent_name, id); |
| } else { |
| struct clk_range range = CLK_RANGE(0, 0); |
| |
| of_at91_get_clk_range(periphclknp, |
| "atmel,clk-output-range", |
| &range); |
| |
| clk = at91_clk_register_sam9x5_peripheral(pmc, name, |
| parent_name, |
| id, &range); |
| } |
| |
| if (IS_ERR(clk)) |
| continue; |
| |
| of_clk_add_provider(periphclknp, of_clk_src_simple_get, clk); |
| } |
| } |
| |
| void __init of_at91rm9200_clk_periph_setup(struct device_node *np, |
| struct at91_pmc *pmc) |
| { |
| of_at91_clk_periph_setup(np, pmc, PERIPHERAL_AT91RM9200); |
| } |
| |
| void __init of_at91sam9x5_clk_periph_setup(struct device_node *np, |
| struct at91_pmc *pmc) |
| { |
| of_at91_clk_periph_setup(np, pmc, PERIPHERAL_AT91SAM9X5); |
| } |