diff options
Diffstat (limited to 'drivers/clk/ti/fapll.c')
-rw-r--r-- | drivers/clk/ti/fapll.c | 410 |
1 files changed, 410 insertions, 0 deletions
diff --git a/drivers/clk/ti/fapll.c b/drivers/clk/ti/fapll.c new file mode 100644 index 0000000..6ef8963 --- /dev/null +++ b/drivers/clk/ti/fapll.c @@ -0,0 +1,410 @@ +/* + * 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-provider.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/clk/ti.h> +#include <asm/div64.h> + +/* FAPLL Control Register PLL_CTRL */ +#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) + +/* 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) + +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 int ti_fapll_enable(struct clk_hw *hw) +{ + struct fapll_data *fd = to_fapll(hw); + u32 v = readl_relaxed(fd->base); + + v |= (1 << FAPLL_MAIN_PLLEN); + writel_relaxed(v, fd->base); + + 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 &= ~(1 << 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 & (1 << 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; + long long 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 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, +}; + +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; + long long 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 8. + */ + 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 *= 8; + } + + /* Synth ost-divider M */ + synth_div_m = readl_relaxed(synth->div) & 0xff; + do_div(rate, synth_div_m); + + return rate; +} + +static 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, +}; + +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; + + 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; + + return clk_register(NULL, &synth->hw); + +free: + kfree(synth); + kfree(init); + + return ERR_PTR(-ENOMEM); +} + +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; + } + + parent_name[0] = of_clk_get_parent_name(node, 0); + parent_name[1] = of_clk_get_parent_name(node, 1); + 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 = 0; + div = 0; + } else { + /* Does the synthesizer have a FREQ register? */ + v = readl_relaxed(freq); + if (!v) + freq = 0; + } + 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); |