| /* |
| * Helper routines for SuperH Clock Pulse Generator blocks (CPG). |
| * |
| * Copyright (C) 2010 Magnus Damm |
| * Copyright (C) 2010 - 2012 Paul Mundt |
| * |
| * This file is subject to the terms and conditions of the GNU General Public |
| * License. See the file "COPYING" in the main directory of this archive |
| * for more details. |
| */ |
| #include <linux/clk.h> |
| #include <linux/compiler.h> |
| #include <linux/slab.h> |
| #include <linux/io.h> |
| #include <linux/sh_clk.h> |
| |
| #define CPG_CKSTP_BIT BIT(8) |
| |
| static unsigned int sh_clk_read(struct clk *clk) |
| { |
| if (clk->flags & CLK_ENABLE_REG_8BIT) |
| return ioread8(clk->mapped_reg); |
| else if (clk->flags & CLK_ENABLE_REG_16BIT) |
| return ioread16(clk->mapped_reg); |
| |
| return ioread32(clk->mapped_reg); |
| } |
| |
| static void sh_clk_write(int value, struct clk *clk) |
| { |
| if (clk->flags & CLK_ENABLE_REG_8BIT) |
| iowrite8(value, clk->mapped_reg); |
| else if (clk->flags & CLK_ENABLE_REG_16BIT) |
| iowrite16(value, clk->mapped_reg); |
| else |
| iowrite32(value, clk->mapped_reg); |
| } |
| |
| static int sh_clk_mstp_enable(struct clk *clk) |
| { |
| sh_clk_write(sh_clk_read(clk) & ~(1 << clk->enable_bit), clk); |
| return 0; |
| } |
| |
| static void sh_clk_mstp_disable(struct clk *clk) |
| { |
| sh_clk_write(sh_clk_read(clk) | (1 << clk->enable_bit), clk); |
| } |
| |
| static struct sh_clk_ops sh_clk_mstp_clk_ops = { |
| .enable = sh_clk_mstp_enable, |
| .disable = sh_clk_mstp_disable, |
| .recalc = followparent_recalc, |
| }; |
| |
| int __init sh_clk_mstp_register(struct clk *clks, int nr) |
| { |
| struct clk *clkp; |
| int ret = 0; |
| int k; |
| |
| for (k = 0; !ret && (k < nr); k++) { |
| clkp = clks + k; |
| clkp->ops = &sh_clk_mstp_clk_ops; |
| ret |= clk_register(clkp); |
| } |
| |
| return ret; |
| } |
| |
| /* |
| * Div/mult table lookup helpers |
| */ |
| static inline struct clk_div_table *clk_to_div_table(struct clk *clk) |
| { |
| return clk->priv; |
| } |
| |
| static inline struct clk_div_mult_table *clk_to_div_mult_table(struct clk *clk) |
| { |
| return clk_to_div_table(clk)->div_mult_table; |
| } |
| |
| /* |
| * Common div ops |
| */ |
| static long sh_clk_div_round_rate(struct clk *clk, unsigned long rate) |
| { |
| return clk_rate_table_round(clk, clk->freq_table, rate); |
| } |
| |
| static unsigned long sh_clk_div_recalc(struct clk *clk) |
| { |
| struct clk_div_mult_table *table = clk_to_div_mult_table(clk); |
| unsigned int idx; |
| |
| clk_rate_table_build(clk, clk->freq_table, table->nr_divisors, |
| table, clk->arch_flags ? &clk->arch_flags : NULL); |
| |
| idx = (sh_clk_read(clk) >> clk->enable_bit) & clk->div_mask; |
| |
| return clk->freq_table[idx].frequency; |
| } |
| |
| static int sh_clk_div_set_rate(struct clk *clk, unsigned long rate) |
| { |
| struct clk_div_table *dt = clk_to_div_table(clk); |
| unsigned long value; |
| int idx; |
| |
| idx = clk_rate_table_find(clk, clk->freq_table, rate); |
| if (idx < 0) |
| return idx; |
| |
| value = sh_clk_read(clk); |
| value &= ~(clk->div_mask << clk->enable_bit); |
| value |= (idx << clk->enable_bit); |
| sh_clk_write(value, clk); |
| |
| /* XXX: Should use a post-change notifier */ |
| if (dt->kick) |
| dt->kick(clk); |
| |
| return 0; |
| } |
| |
| static int sh_clk_div_enable(struct clk *clk) |
| { |
| sh_clk_write(sh_clk_read(clk) & ~CPG_CKSTP_BIT, clk); |
| return 0; |
| } |
| |
| static void sh_clk_div_disable(struct clk *clk) |
| { |
| unsigned int val; |
| |
| val = sh_clk_read(clk); |
| val |= CPG_CKSTP_BIT; |
| |
| /* |
| * div6 clocks require the divisor field to be non-zero or the |
| * above CKSTP toggle silently fails. Ensure that the divisor |
| * array is reset to its initial state on disable. |
| */ |
| if (clk->flags & CLK_MASK_DIV_ON_DISABLE) |
| val |= clk->div_mask; |
| |
| sh_clk_write(val, clk); |
| } |
| |
| static struct sh_clk_ops sh_clk_div_clk_ops = { |
| .recalc = sh_clk_div_recalc, |
| .set_rate = sh_clk_div_set_rate, |
| .round_rate = sh_clk_div_round_rate, |
| }; |
| |
| static struct sh_clk_ops sh_clk_div_enable_clk_ops = { |
| .recalc = sh_clk_div_recalc, |
| .set_rate = sh_clk_div_set_rate, |
| .round_rate = sh_clk_div_round_rate, |
| .enable = sh_clk_div_enable, |
| .disable = sh_clk_div_disable, |
| }; |
| |
| static int __init sh_clk_init_parent(struct clk *clk) |
| { |
| u32 val; |
| |
| if (clk->parent) |
| return 0; |
| |
| if (!clk->parent_table || !clk->parent_num) |
| return 0; |
| |
| if (!clk->src_width) { |
| pr_err("sh_clk_init_parent: cannot select parent clock\n"); |
| return -EINVAL; |
| } |
| |
| val = (sh_clk_read(clk) >> clk->src_shift); |
| val &= (1 << clk->src_width) - 1; |
| |
| if (val >= clk->parent_num) { |
| pr_err("sh_clk_init_parent: parent table size failed\n"); |
| return -EINVAL; |
| } |
| |
| clk_reparent(clk, clk->parent_table[val]); |
| if (!clk->parent) { |
| pr_err("sh_clk_init_parent: unable to set parent"); |
| return -EINVAL; |
| } |
| |
| return 0; |
| } |
| |
| static int __init sh_clk_div_register_ops(struct clk *clks, int nr, |
| struct clk_div_table *table, struct sh_clk_ops *ops) |
| { |
| struct clk *clkp; |
| void *freq_table; |
| int nr_divs = table->div_mult_table->nr_divisors; |
| int freq_table_size = sizeof(struct cpufreq_frequency_table); |
| int ret = 0; |
| int k; |
| |
| freq_table_size *= (nr_divs + 1); |
| freq_table = kzalloc(freq_table_size * nr, GFP_KERNEL); |
| if (!freq_table) { |
| pr_err("%s: unable to alloc memory\n", __func__); |
| return -ENOMEM; |
| } |
| |
| for (k = 0; !ret && (k < nr); k++) { |
| clkp = clks + k; |
| |
| clkp->ops = ops; |
| clkp->priv = table; |
| |
| clkp->freq_table = freq_table + (k * freq_table_size); |
| clkp->freq_table[nr_divs].frequency = CPUFREQ_TABLE_END; |
| |
| ret = clk_register(clkp); |
| if (ret == 0) |
| ret = sh_clk_init_parent(clkp); |
| } |
| |
| return ret; |
| } |
| |
| /* |
| * div6 support |
| */ |
| static int sh_clk_div6_divisors[64] = { |
| 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, |
| 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, |
| 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, |
| 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64 |
| }; |
| |
| static struct clk_div_mult_table div6_div_mult_table = { |
| .divisors = sh_clk_div6_divisors, |
| .nr_divisors = ARRAY_SIZE(sh_clk_div6_divisors), |
| }; |
| |
| static struct clk_div_table sh_clk_div6_table = { |
| .div_mult_table = &div6_div_mult_table, |
| }; |
| |
| static int sh_clk_div6_set_parent(struct clk *clk, struct clk *parent) |
| { |
| struct clk_div_mult_table *table = clk_to_div_mult_table(clk); |
| u32 value; |
| int ret, i; |
| |
| if (!clk->parent_table || !clk->parent_num) |
| return -EINVAL; |
| |
| /* Search the parent */ |
| for (i = 0; i < clk->parent_num; i++) |
| if (clk->parent_table[i] == parent) |
| break; |
| |
| if (i == clk->parent_num) |
| return -ENODEV; |
| |
| ret = clk_reparent(clk, parent); |
| if (ret < 0) |
| return ret; |
| |
| value = sh_clk_read(clk) & |
| ~(((1 << clk->src_width) - 1) << clk->src_shift); |
| |
| sh_clk_write(value | (i << clk->src_shift), clk); |
| |
| /* Rebuild the frequency table */ |
| clk_rate_table_build(clk, clk->freq_table, table->nr_divisors, |
| table, NULL); |
| |
| return 0; |
| } |
| |
| static struct sh_clk_ops sh_clk_div6_reparent_clk_ops = { |
| .recalc = sh_clk_div_recalc, |
| .round_rate = sh_clk_div_round_rate, |
| .set_rate = sh_clk_div_set_rate, |
| .enable = sh_clk_div_enable, |
| .disable = sh_clk_div_disable, |
| .set_parent = sh_clk_div6_set_parent, |
| }; |
| |
| int __init sh_clk_div6_register(struct clk *clks, int nr) |
| { |
| return sh_clk_div_register_ops(clks, nr, &sh_clk_div6_table, |
| &sh_clk_div_enable_clk_ops); |
| } |
| |
| int __init sh_clk_div6_reparent_register(struct clk *clks, int nr) |
| { |
| return sh_clk_div_register_ops(clks, nr, &sh_clk_div6_table, |
| &sh_clk_div6_reparent_clk_ops); |
| } |
| |
| /* |
| * div4 support |
| */ |
| static int sh_clk_div4_set_parent(struct clk *clk, struct clk *parent) |
| { |
| struct clk_div_mult_table *table = clk_to_div_mult_table(clk); |
| u32 value; |
| int ret; |
| |
| /* we really need a better way to determine parent index, but for |
| * now assume internal parent comes with CLK_ENABLE_ON_INIT set, |
| * no CLK_ENABLE_ON_INIT means external clock... |
| */ |
| |
| if (parent->flags & CLK_ENABLE_ON_INIT) |
| value = sh_clk_read(clk) & ~(1 << 7); |
| else |
| value = sh_clk_read(clk) | (1 << 7); |
| |
| ret = clk_reparent(clk, parent); |
| if (ret < 0) |
| return ret; |
| |
| sh_clk_write(value, clk); |
| |
| /* Rebiuld the frequency table */ |
| clk_rate_table_build(clk, clk->freq_table, table->nr_divisors, |
| table, &clk->arch_flags); |
| |
| return 0; |
| } |
| |
| static struct sh_clk_ops sh_clk_div4_reparent_clk_ops = { |
| .recalc = sh_clk_div_recalc, |
| .set_rate = sh_clk_div_set_rate, |
| .round_rate = sh_clk_div_round_rate, |
| .enable = sh_clk_div_enable, |
| .disable = sh_clk_div_disable, |
| .set_parent = sh_clk_div4_set_parent, |
| }; |
| |
| int __init sh_clk_div4_register(struct clk *clks, int nr, |
| struct clk_div4_table *table) |
| { |
| return sh_clk_div_register_ops(clks, nr, table, &sh_clk_div_clk_ops); |
| } |
| |
| int __init sh_clk_div4_enable_register(struct clk *clks, int nr, |
| struct clk_div4_table *table) |
| { |
| return sh_clk_div_register_ops(clks, nr, table, |
| &sh_clk_div_enable_clk_ops); |
| } |
| |
| int __init sh_clk_div4_reparent_register(struct clk *clks, int nr, |
| struct clk_div4_table *table) |
| { |
| return sh_clk_div_register_ops(clks, nr, table, |
| &sh_clk_div4_reparent_clk_ops); |
| } |