diff options
Diffstat (limited to 'drivers/clk/ti/fapll.c')
-rw-r--r-- | drivers/clk/ti/fapll.c | 671 |
1 files changed, 671 insertions, 0 deletions
diff --git a/drivers/clk/ti/fapll.c b/drivers/clk/ti/fapll.c new file mode 100644 index 000000000..e33ce8518 --- /dev/null +++ b/drivers/clk/ti/fapll.c @@ -0,0 +1,671 @@ +/* + * 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 version 2. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether express or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/math64.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/clk/ti.h> + +/* FAPLL Control Register PLL_CTRL */ +#define FAPLL_MAIN_MULT_N_SHIFT 16 +#define FAPLL_MAIN_DIV_P_SHIFT 8 +#define FAPLL_MAIN_LOCK BIT(7) +#define FAPLL_MAIN_PLLEN BIT(3) +#define FAPLL_MAIN_BP BIT(2) +#define FAPLL_MAIN_LOC_CTL BIT(0) + +#define FAPLL_MAIN_MAX_MULT_N 0xffff +#define FAPLL_MAIN_MAX_DIV_P 0xff +#define FAPLL_MAIN_CLEAR_MASK \ + ((FAPLL_MAIN_MAX_MULT_N << FAPLL_MAIN_MULT_N_SHIFT) | \ + (FAPLL_MAIN_DIV_P_SHIFT << FAPLL_MAIN_DIV_P_SHIFT) | \ + FAPLL_MAIN_LOC_CTL) + +/* FAPLL powerdown register PWD */ +#define FAPLL_PWD_OFFSET 4 + +#define MAX_FAPLL_OUTPUTS 7 +#define FAPLL_MAX_RETRIES 1000 + +#define to_fapll(_hw) container_of(_hw, struct fapll_data, hw) +#define to_synth(_hw) container_of(_hw, struct fapll_synth, hw) + +/* The bypass bit is inverted on the ddr_pll.. */ +#define fapll_is_ddr_pll(va) (((u32)(va) & 0xffff) == 0x0440) + +/* + * The audio_pll_clk1 input is hard wired to the 27MHz bypass clock, + * and the audio_pll_clk1 synthesizer is hardwared to 32KiHz output. + */ +#define is_ddr_pll_clk1(va) (((u32)(va) & 0xffff) == 0x044c) +#define is_audio_pll_clk1(va) (((u32)(va) & 0xffff) == 0x04a8) + +/* Synthesizer divider register */ +#define SYNTH_LDMDIV1 BIT(8) + +/* Synthesizer frequency register */ +#define SYNTH_LDFREQ BIT(31) + +#define SYNTH_PHASE_K 8 +#define SYNTH_MAX_INT_DIV 0xf +#define SYNTH_MAX_DIV_M 0xff + +struct fapll_data { + struct clk_hw hw; + void __iomem *base; + const char *name; + struct clk *clk_ref; + struct clk *clk_bypass; + struct clk_onecell_data outputs; + bool bypass_bit_inverted; +}; + +struct fapll_synth { + struct clk_hw hw; + struct fapll_data *fd; + int index; + void __iomem *freq; + void __iomem *div; + const char *name; + struct clk *clk_pll; +}; + +static bool ti_fapll_clock_is_bypass(struct fapll_data *fd) +{ + u32 v = readl_relaxed(fd->base); + + if (fd->bypass_bit_inverted) + return !(v & FAPLL_MAIN_BP); + else + return !!(v & FAPLL_MAIN_BP); +} + +static void ti_fapll_set_bypass(struct fapll_data *fd) +{ + u32 v = readl_relaxed(fd->base); + + if (fd->bypass_bit_inverted) + v &= ~FAPLL_MAIN_BP; + else + v |= FAPLL_MAIN_BP; + writel_relaxed(v, fd->base); +} + +static void ti_fapll_clear_bypass(struct fapll_data *fd) +{ + u32 v = readl_relaxed(fd->base); + + if (fd->bypass_bit_inverted) + v |= FAPLL_MAIN_BP; + else + v &= ~FAPLL_MAIN_BP; + writel_relaxed(v, fd->base); +} + +static int ti_fapll_wait_lock(struct fapll_data *fd) +{ + int retries = FAPLL_MAX_RETRIES; + u32 v; + + while ((v = readl_relaxed(fd->base))) { + if (v & FAPLL_MAIN_LOCK) + return 0; + + if (retries-- <= 0) + break; + + udelay(1); + } + + pr_err("%s failed to lock\n", fd->name); + + return -ETIMEDOUT; +} + +static int ti_fapll_enable(struct clk_hw *hw) +{ + struct fapll_data *fd = to_fapll(hw); + u32 v = readl_relaxed(fd->base); + + v |= FAPLL_MAIN_PLLEN; + writel_relaxed(v, fd->base); + ti_fapll_wait_lock(fd); + + return 0; +} + +static void ti_fapll_disable(struct clk_hw *hw) +{ + struct fapll_data *fd = to_fapll(hw); + u32 v = readl_relaxed(fd->base); + + v &= ~FAPLL_MAIN_PLLEN; + writel_relaxed(v, fd->base); +} + +static int ti_fapll_is_enabled(struct clk_hw *hw) +{ + struct fapll_data *fd = to_fapll(hw); + u32 v = readl_relaxed(fd->base); + + return v & FAPLL_MAIN_PLLEN; +} + +static unsigned long ti_fapll_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct fapll_data *fd = to_fapll(hw); + u32 fapll_n, fapll_p, v; + u64 rate; + + if (ti_fapll_clock_is_bypass(fd)) + return parent_rate; + + rate = parent_rate; + + /* PLL pre-divider is P and multiplier is N */ + v = readl_relaxed(fd->base); + fapll_p = (v >> 8) & 0xff; + if (fapll_p) + do_div(rate, fapll_p); + fapll_n = v >> 16; + if (fapll_n) + rate *= fapll_n; + + return rate; +} + +static u8 ti_fapll_get_parent(struct clk_hw *hw) +{ + struct fapll_data *fd = to_fapll(hw); + + if (ti_fapll_clock_is_bypass(fd)) + return 1; + + return 0; +} + +static int ti_fapll_set_div_mult(unsigned long rate, + unsigned long parent_rate, + u32 *pre_div_p, u32 *mult_n) +{ + /* + * So far no luck getting decent clock with PLL divider, + * PLL does not seem to lock and the signal does not look + * right. It seems the divider can only be used together + * with the multiplier? + */ + if (rate < parent_rate) { + pr_warn("FAPLL main divider rates unsupported\n"); + return -EINVAL; + } + + *mult_n = rate / parent_rate; + if (*mult_n > FAPLL_MAIN_MAX_MULT_N) + return -EINVAL; + *pre_div_p = 1; + + return 0; +} + +static long ti_fapll_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + u32 pre_div_p, mult_n; + int error; + + if (!rate) + return -EINVAL; + + error = ti_fapll_set_div_mult(rate, *parent_rate, + &pre_div_p, &mult_n); + if (error) + return error; + + rate = *parent_rate / pre_div_p; + rate *= mult_n; + + return rate; +} + +static int ti_fapll_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct fapll_data *fd = to_fapll(hw); + u32 pre_div_p, mult_n, v; + int error; + + if (!rate) + return -EINVAL; + + error = ti_fapll_set_div_mult(rate, parent_rate, + &pre_div_p, &mult_n); + if (error) + return error; + + ti_fapll_set_bypass(fd); + v = readl_relaxed(fd->base); + v &= ~FAPLL_MAIN_CLEAR_MASK; + v |= pre_div_p << FAPLL_MAIN_DIV_P_SHIFT; + v |= mult_n << FAPLL_MAIN_MULT_N_SHIFT; + writel_relaxed(v, fd->base); + if (ti_fapll_is_enabled(hw)) + ti_fapll_wait_lock(fd); + ti_fapll_clear_bypass(fd); + + return 0; +} + +static const struct clk_ops ti_fapll_ops = { + .enable = ti_fapll_enable, + .disable = ti_fapll_disable, + .is_enabled = ti_fapll_is_enabled, + .recalc_rate = ti_fapll_recalc_rate, + .get_parent = ti_fapll_get_parent, + .round_rate = ti_fapll_round_rate, + .set_rate = ti_fapll_set_rate, +}; + +static int ti_fapll_synth_enable(struct clk_hw *hw) +{ + struct fapll_synth *synth = to_synth(hw); + u32 v = readl_relaxed(synth->fd->base + FAPLL_PWD_OFFSET); + + v &= ~(1 << synth->index); + writel_relaxed(v, synth->fd->base + FAPLL_PWD_OFFSET); + + return 0; +} + +static void ti_fapll_synth_disable(struct clk_hw *hw) +{ + struct fapll_synth *synth = to_synth(hw); + u32 v = readl_relaxed(synth->fd->base + FAPLL_PWD_OFFSET); + + v |= 1 << synth->index; + writel_relaxed(v, synth->fd->base + FAPLL_PWD_OFFSET); +} + +static int ti_fapll_synth_is_enabled(struct clk_hw *hw) +{ + struct fapll_synth *synth = to_synth(hw); + u32 v = readl_relaxed(synth->fd->base + FAPLL_PWD_OFFSET); + + return !(v & (1 << synth->index)); +} + +/* + * See dm816x TRM chapter 1.10.3 Flying Adder PLL fore more info + */ +static unsigned long ti_fapll_synth_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct fapll_synth *synth = to_synth(hw); + u32 synth_div_m; + u64 rate; + + /* The audio_pll_clk1 is hardwired to produce 32.768KiHz clock */ + if (!synth->div) + return 32768; + + /* + * PLL in bypass sets the synths in bypass mode too. The PLL rate + * can be also be set to 27MHz, so we can't use parent_rate to + * check for bypass mode. + */ + if (ti_fapll_clock_is_bypass(synth->fd)) + return parent_rate; + + rate = parent_rate; + + /* + * Synth frequency integer and fractional divider. + * Note that the phase output K is 8, so the result needs + * to be multiplied by SYNTH_PHASE_K. + */ + if (synth->freq) { + u32 v, synth_int_div, synth_frac_div, synth_div_freq; + + v = readl_relaxed(synth->freq); + synth_int_div = (v >> 24) & 0xf; + synth_frac_div = v & 0xffffff; + synth_div_freq = (synth_int_div * 10000000) + synth_frac_div; + rate *= 10000000; + do_div(rate, synth_div_freq); + rate *= SYNTH_PHASE_K; + } + + /* Synth post-divider M */ + synth_div_m = readl_relaxed(synth->div) & SYNTH_MAX_DIV_M; + + return DIV_ROUND_UP_ULL(rate, synth_div_m); +} + +static unsigned long ti_fapll_synth_get_frac_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct fapll_synth *synth = to_synth(hw); + unsigned long current_rate, frac_rate; + u32 post_div_m; + + current_rate = ti_fapll_synth_recalc_rate(hw, parent_rate); + post_div_m = readl_relaxed(synth->div) & SYNTH_MAX_DIV_M; + frac_rate = current_rate * post_div_m; + + return frac_rate; +} + +static u32 ti_fapll_synth_set_frac_rate(struct fapll_synth *synth, + unsigned long rate, + unsigned long parent_rate) +{ + u32 post_div_m, synth_int_div = 0, synth_frac_div = 0, v; + + post_div_m = DIV_ROUND_UP_ULL((u64)parent_rate * SYNTH_PHASE_K, rate); + post_div_m = post_div_m / SYNTH_MAX_INT_DIV; + if (post_div_m > SYNTH_MAX_DIV_M) + return -EINVAL; + if (!post_div_m) + post_div_m = 1; + + for (; post_div_m < SYNTH_MAX_DIV_M; post_div_m++) { + synth_int_div = DIV_ROUND_UP_ULL((u64)parent_rate * + SYNTH_PHASE_K * + 10000000, + rate * post_div_m); + synth_frac_div = synth_int_div % 10000000; + synth_int_div /= 10000000; + + if (synth_int_div <= SYNTH_MAX_INT_DIV) + break; + } + + if (synth_int_div > SYNTH_MAX_INT_DIV) + return -EINVAL; + + v = readl_relaxed(synth->freq); + v &= ~0x1fffffff; + v |= (synth_int_div & SYNTH_MAX_INT_DIV) << 24; + v |= (synth_frac_div & 0xffffff); + v |= SYNTH_LDFREQ; + writel_relaxed(v, synth->freq); + + return post_div_m; +} + +static long ti_fapll_synth_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + struct fapll_synth *synth = to_synth(hw); + struct fapll_data *fd = synth->fd; + unsigned long r; + + if (ti_fapll_clock_is_bypass(fd) || !synth->div || !rate) + return -EINVAL; + + /* Only post divider m available with no fractional divider? */ + if (!synth->freq) { + unsigned long frac_rate; + u32 synth_post_div_m; + + frac_rate = ti_fapll_synth_get_frac_rate(hw, *parent_rate); + synth_post_div_m = DIV_ROUND_UP(frac_rate, rate); + r = DIV_ROUND_UP(frac_rate, synth_post_div_m); + goto out; + } + + r = *parent_rate * SYNTH_PHASE_K; + if (rate > r) + goto out; + + r = DIV_ROUND_UP_ULL(r, SYNTH_MAX_INT_DIV * SYNTH_MAX_DIV_M); + if (rate < r) + goto out; + + r = rate; +out: + return r; +} + +static int ti_fapll_synth_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct fapll_synth *synth = to_synth(hw); + struct fapll_data *fd = synth->fd; + unsigned long frac_rate, post_rate = 0; + u32 post_div_m = 0, v; + + if (ti_fapll_clock_is_bypass(fd) || !synth->div || !rate) + return -EINVAL; + + /* Produce the rate with just post divider M? */ + frac_rate = ti_fapll_synth_get_frac_rate(hw, parent_rate); + if (frac_rate < rate) { + if (!synth->freq) + return -EINVAL; + } else { + post_div_m = DIV_ROUND_UP(frac_rate, rate); + if (post_div_m && (post_div_m <= SYNTH_MAX_DIV_M)) + post_rate = DIV_ROUND_UP(frac_rate, post_div_m); + if (!synth->freq && !post_rate) + return -EINVAL; + } + + /* Need to recalculate the fractional divider? */ + if ((post_rate != rate) && synth->freq) + post_div_m = ti_fapll_synth_set_frac_rate(synth, + rate, + parent_rate); + + v = readl_relaxed(synth->div); + v &= ~SYNTH_MAX_DIV_M; + v |= post_div_m; + v |= SYNTH_LDMDIV1; + writel_relaxed(v, synth->div); + + return 0; +} + +static const struct clk_ops ti_fapll_synt_ops = { + .enable = ti_fapll_synth_enable, + .disable = ti_fapll_synth_disable, + .is_enabled = ti_fapll_synth_is_enabled, + .recalc_rate = ti_fapll_synth_recalc_rate, + .round_rate = ti_fapll_synth_round_rate, + .set_rate = ti_fapll_synth_set_rate, +}; + +static struct clk * __init ti_fapll_synth_setup(struct fapll_data *fd, + void __iomem *freq, + void __iomem *div, + int index, + const char *name, + const char *parent, + struct clk *pll_clk) +{ + struct clk_init_data *init; + struct fapll_synth *synth; + struct clk *clk = ERR_PTR(-ENOMEM); + + init = kzalloc(sizeof(*init), GFP_KERNEL); + if (!init) + return ERR_PTR(-ENOMEM); + + init->ops = &ti_fapll_synt_ops; + init->name = name; + init->parent_names = &parent; + init->num_parents = 1; + + synth = kzalloc(sizeof(*synth), GFP_KERNEL); + if (!synth) + goto free; + + synth->fd = fd; + synth->index = index; + synth->freq = freq; + synth->div = div; + synth->name = name; + synth->hw.init = init; + synth->clk_pll = pll_clk; + + clk = clk_register(NULL, &synth->hw); + if (IS_ERR(clk)) { + pr_err("failed to register clock\n"); + goto free; + } + + return clk; + +free: + kfree(synth); + kfree(init); + + return clk; +} + +static void __init ti_fapll_setup(struct device_node *node) +{ + struct fapll_data *fd; + struct clk_init_data *init = NULL; + const char *parent_name[2]; + struct clk *pll_clk; + int i; + + fd = kzalloc(sizeof(*fd), GFP_KERNEL); + if (!fd) + return; + + fd->outputs.clks = kzalloc(sizeof(struct clk *) * + MAX_FAPLL_OUTPUTS + 1, + GFP_KERNEL); + if (!fd->outputs.clks) + goto free; + + init = kzalloc(sizeof(*init), GFP_KERNEL); + if (!init) + goto free; + + init->ops = &ti_fapll_ops; + init->name = node->name; + + init->num_parents = of_clk_get_parent_count(node); + if (init->num_parents != 2) { + pr_err("%s must have two parents\n", node->name); + goto free; + } + + of_clk_parent_fill(node, parent_name, 2); + init->parent_names = parent_name; + + fd->clk_ref = of_clk_get(node, 0); + if (IS_ERR(fd->clk_ref)) { + pr_err("%s could not get clk_ref\n", node->name); + goto free; + } + + fd->clk_bypass = of_clk_get(node, 1); + if (IS_ERR(fd->clk_bypass)) { + pr_err("%s could not get clk_bypass\n", node->name); + goto free; + } + + fd->base = of_iomap(node, 0); + if (!fd->base) { + pr_err("%s could not get IO base\n", node->name); + goto free; + } + + if (fapll_is_ddr_pll(fd->base)) + fd->bypass_bit_inverted = true; + + fd->name = node->name; + fd->hw.init = init; + + /* Register the parent PLL */ + pll_clk = clk_register(NULL, &fd->hw); + if (IS_ERR(pll_clk)) + goto unmap; + + fd->outputs.clks[0] = pll_clk; + fd->outputs.clk_num++; + + /* + * Set up the child synthesizers starting at index 1 as the + * PLL output is at index 0. We need to check the clock-indices + * for numbering in case there are holes in the synth mapping, + * and then probe the synth register to see if it has a FREQ + * register available. + */ + for (i = 0; i < MAX_FAPLL_OUTPUTS; i++) { + const char *output_name; + void __iomem *freq, *div; + struct clk *synth_clk; + int output_instance; + u32 v; + + if (of_property_read_string_index(node, "clock-output-names", + i, &output_name)) + continue; + + if (of_property_read_u32_index(node, "clock-indices", i, + &output_instance)) + output_instance = i; + + freq = fd->base + (output_instance * 8); + div = freq + 4; + + /* Check for hardwired audio_pll_clk1 */ + if (is_audio_pll_clk1(freq)) { + freq = NULL; + div = NULL; + } else { + /* Does the synthesizer have a FREQ register? */ + v = readl_relaxed(freq); + if (!v) + freq = NULL; + } + synth_clk = ti_fapll_synth_setup(fd, freq, div, output_instance, + output_name, node->name, + pll_clk); + if (IS_ERR(synth_clk)) + continue; + + fd->outputs.clks[output_instance] = synth_clk; + fd->outputs.clk_num++; + + clk_register_clkdev(synth_clk, output_name, NULL); + } + + /* Register the child synthesizers as the FAPLL outputs */ + of_clk_add_provider(node, of_clk_src_onecell_get, &fd->outputs); + /* Add clock alias for the outputs */ + + kfree(init); + + return; + +unmap: + iounmap(fd->base); +free: + if (fd->clk_bypass) + clk_put(fd->clk_bypass); + if (fd->clk_ref) + clk_put(fd->clk_ref); + kfree(fd->outputs.clks); + kfree(fd); + kfree(init); +} + +CLK_OF_DECLARE(ti_fapll_clock, "ti,dm816-fapll-clock", ti_fapll_setup); |