diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/clk/at91/sckc.c | 633 |
1 files changed, 633 insertions, 0 deletions
diff --git a/drivers/clk/at91/sckc.c b/drivers/clk/at91/sckc.c new file mode 100644 index 000000000..fdc9b669f --- /dev/null +++ b/drivers/clk/at91/sckc.c @@ -0,0 +1,633 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * drivers/clk/at91/sckc.c + * + * Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com> + */ + +#include <linux/clk-provider.h> +#include <linux/clkdev.h> +#include <linux/delay.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/io.h> + +#define SLOW_CLOCK_FREQ 32768 +#define SLOWCK_SW_CYCLES 5 +#define SLOWCK_SW_TIME_USEC ((SLOWCK_SW_CYCLES * USEC_PER_SEC) / \ + SLOW_CLOCK_FREQ) + +#define AT91_SCKC_CR 0x00 + +struct clk_slow_bits { + u32 cr_rcen; + u32 cr_osc32en; + u32 cr_osc32byp; + u32 cr_oscsel; +}; + +struct clk_slow_osc { + struct clk_hw hw; + void __iomem *sckcr; + const struct clk_slow_bits *bits; + unsigned long startup_usec; +}; + +#define to_clk_slow_osc(hw) container_of(hw, struct clk_slow_osc, hw) + +struct clk_sama5d4_slow_osc { + struct clk_hw hw; + void __iomem *sckcr; + const struct clk_slow_bits *bits; + unsigned long startup_usec; + bool prepared; +}; + +#define to_clk_sama5d4_slow_osc(hw) container_of(hw, struct clk_sama5d4_slow_osc, hw) + +struct clk_slow_rc_osc { + struct clk_hw hw; + void __iomem *sckcr; + const struct clk_slow_bits *bits; + unsigned long frequency; + unsigned long accuracy; + unsigned long startup_usec; +}; + +#define to_clk_slow_rc_osc(hw) container_of(hw, struct clk_slow_rc_osc, hw) + +struct clk_sam9x5_slow { + struct clk_hw hw; + void __iomem *sckcr; + const struct clk_slow_bits *bits; + u8 parent; +}; + +#define to_clk_sam9x5_slow(hw) container_of(hw, struct clk_sam9x5_slow, hw) + +static int clk_slow_osc_prepare(struct clk_hw *hw) +{ + struct clk_slow_osc *osc = to_clk_slow_osc(hw); + void __iomem *sckcr = osc->sckcr; + u32 tmp = readl(sckcr); + + if (tmp & (osc->bits->cr_osc32byp | osc->bits->cr_osc32en)) + return 0; + + writel(tmp | osc->bits->cr_osc32en, sckcr); + + if (system_state < SYSTEM_RUNNING) + udelay(osc->startup_usec); + else + usleep_range(osc->startup_usec, osc->startup_usec + 1); + + return 0; +} + +static void clk_slow_osc_unprepare(struct clk_hw *hw) +{ + struct clk_slow_osc *osc = to_clk_slow_osc(hw); + void __iomem *sckcr = osc->sckcr; + u32 tmp = readl(sckcr); + + if (tmp & osc->bits->cr_osc32byp) + return; + + writel(tmp & ~osc->bits->cr_osc32en, sckcr); +} + +static int clk_slow_osc_is_prepared(struct clk_hw *hw) +{ + struct clk_slow_osc *osc = to_clk_slow_osc(hw); + void __iomem *sckcr = osc->sckcr; + u32 tmp = readl(sckcr); + + if (tmp & osc->bits->cr_osc32byp) + return 1; + + return !!(tmp & osc->bits->cr_osc32en); +} + +static const struct clk_ops slow_osc_ops = { + .prepare = clk_slow_osc_prepare, + .unprepare = clk_slow_osc_unprepare, + .is_prepared = clk_slow_osc_is_prepared, +}; + +static struct clk_hw * __init +at91_clk_register_slow_osc(void __iomem *sckcr, + const char *name, + const char *parent_name, + unsigned long startup, + bool bypass, + const struct clk_slow_bits *bits) +{ + struct clk_slow_osc *osc; + struct clk_hw *hw; + struct clk_init_data init; + int ret; + + if (!sckcr || !name || !parent_name) + return ERR_PTR(-EINVAL); + + osc = kzalloc(sizeof(*osc), GFP_KERNEL); + if (!osc) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.ops = &slow_osc_ops; + init.parent_names = &parent_name; + init.num_parents = 1; + init.flags = CLK_IGNORE_UNUSED; + + osc->hw.init = &init; + osc->sckcr = sckcr; + osc->startup_usec = startup; + osc->bits = bits; + + if (bypass) + writel((readl(sckcr) & ~osc->bits->cr_osc32en) | + osc->bits->cr_osc32byp, sckcr); + + hw = &osc->hw; + ret = clk_hw_register(NULL, &osc->hw); + if (ret) { + kfree(osc); + hw = ERR_PTR(ret); + } + + return hw; +} + +static void at91_clk_unregister_slow_osc(struct clk_hw *hw) +{ + struct clk_slow_osc *osc = to_clk_slow_osc(hw); + + clk_hw_unregister(hw); + kfree(osc); +} + +static unsigned long clk_slow_rc_osc_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_slow_rc_osc *osc = to_clk_slow_rc_osc(hw); + + return osc->frequency; +} + +static unsigned long clk_slow_rc_osc_recalc_accuracy(struct clk_hw *hw, + unsigned long parent_acc) +{ + struct clk_slow_rc_osc *osc = to_clk_slow_rc_osc(hw); + + return osc->accuracy; +} + +static int clk_slow_rc_osc_prepare(struct clk_hw *hw) +{ + struct clk_slow_rc_osc *osc = to_clk_slow_rc_osc(hw); + void __iomem *sckcr = osc->sckcr; + + writel(readl(sckcr) | osc->bits->cr_rcen, sckcr); + + if (system_state < SYSTEM_RUNNING) + udelay(osc->startup_usec); + else + usleep_range(osc->startup_usec, osc->startup_usec + 1); + + return 0; +} + +static void clk_slow_rc_osc_unprepare(struct clk_hw *hw) +{ + struct clk_slow_rc_osc *osc = to_clk_slow_rc_osc(hw); + void __iomem *sckcr = osc->sckcr; + + writel(readl(sckcr) & ~osc->bits->cr_rcen, sckcr); +} + +static int clk_slow_rc_osc_is_prepared(struct clk_hw *hw) +{ + struct clk_slow_rc_osc *osc = to_clk_slow_rc_osc(hw); + + return !!(readl(osc->sckcr) & osc->bits->cr_rcen); +} + +static const struct clk_ops slow_rc_osc_ops = { + .prepare = clk_slow_rc_osc_prepare, + .unprepare = clk_slow_rc_osc_unprepare, + .is_prepared = clk_slow_rc_osc_is_prepared, + .recalc_rate = clk_slow_rc_osc_recalc_rate, + .recalc_accuracy = clk_slow_rc_osc_recalc_accuracy, +}; + +static struct clk_hw * __init +at91_clk_register_slow_rc_osc(void __iomem *sckcr, + const char *name, + unsigned long frequency, + unsigned long accuracy, + unsigned long startup, + const struct clk_slow_bits *bits) +{ + struct clk_slow_rc_osc *osc; + struct clk_hw *hw; + struct clk_init_data init; + int ret; + + if (!sckcr || !name) + return ERR_PTR(-EINVAL); + + osc = kzalloc(sizeof(*osc), GFP_KERNEL); + if (!osc) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.ops = &slow_rc_osc_ops; + init.parent_names = NULL; + init.num_parents = 0; + init.flags = CLK_IGNORE_UNUSED; + + osc->hw.init = &init; + osc->sckcr = sckcr; + osc->bits = bits; + osc->frequency = frequency; + osc->accuracy = accuracy; + osc->startup_usec = startup; + + hw = &osc->hw; + ret = clk_hw_register(NULL, &osc->hw); + if (ret) { + kfree(osc); + hw = ERR_PTR(ret); + } + + return hw; +} + +static void at91_clk_unregister_slow_rc_osc(struct clk_hw *hw) +{ + struct clk_slow_rc_osc *osc = to_clk_slow_rc_osc(hw); + + clk_hw_unregister(hw); + kfree(osc); +} + +static int clk_sam9x5_slow_set_parent(struct clk_hw *hw, u8 index) +{ + struct clk_sam9x5_slow *slowck = to_clk_sam9x5_slow(hw); + void __iomem *sckcr = slowck->sckcr; + u32 tmp; + + if (index > 1) + return -EINVAL; + + tmp = readl(sckcr); + + if ((!index && !(tmp & slowck->bits->cr_oscsel)) || + (index && (tmp & slowck->bits->cr_oscsel))) + return 0; + + if (index) + tmp |= slowck->bits->cr_oscsel; + else + tmp &= ~slowck->bits->cr_oscsel; + + writel(tmp, sckcr); + + if (system_state < SYSTEM_RUNNING) + udelay(SLOWCK_SW_TIME_USEC); + else + usleep_range(SLOWCK_SW_TIME_USEC, SLOWCK_SW_TIME_USEC + 1); + + return 0; +} + +static u8 clk_sam9x5_slow_get_parent(struct clk_hw *hw) +{ + struct clk_sam9x5_slow *slowck = to_clk_sam9x5_slow(hw); + + return !!(readl(slowck->sckcr) & slowck->bits->cr_oscsel); +} + +static const struct clk_ops sam9x5_slow_ops = { + .set_parent = clk_sam9x5_slow_set_parent, + .get_parent = clk_sam9x5_slow_get_parent, +}; + +static struct clk_hw * __init +at91_clk_register_sam9x5_slow(void __iomem *sckcr, + const char *name, + const char **parent_names, + int num_parents, + const struct clk_slow_bits *bits) +{ + struct clk_sam9x5_slow *slowck; + struct clk_hw *hw; + struct clk_init_data init; + int ret; + + if (!sckcr || !name || !parent_names || !num_parents) + return ERR_PTR(-EINVAL); + + slowck = kzalloc(sizeof(*slowck), GFP_KERNEL); + if (!slowck) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.ops = &sam9x5_slow_ops; + init.parent_names = parent_names; + init.num_parents = num_parents; + init.flags = 0; + + slowck->hw.init = &init; + slowck->sckcr = sckcr; + slowck->bits = bits; + slowck->parent = !!(readl(sckcr) & slowck->bits->cr_oscsel); + + hw = &slowck->hw; + ret = clk_hw_register(NULL, &slowck->hw); + if (ret) { + kfree(slowck); + hw = ERR_PTR(ret); + } + + return hw; +} + +static void at91_clk_unregister_sam9x5_slow(struct clk_hw *hw) +{ + struct clk_sam9x5_slow *slowck = to_clk_sam9x5_slow(hw); + + clk_hw_unregister(hw); + kfree(slowck); +} + +static void __init at91sam9x5_sckc_register(struct device_node *np, + unsigned int rc_osc_startup_us, + const struct clk_slow_bits *bits) +{ + const char *parent_names[2] = { "slow_rc_osc", "slow_osc" }; + void __iomem *regbase = of_iomap(np, 0); + struct device_node *child = NULL; + const char *xtal_name; + struct clk_hw *slow_rc, *slow_osc, *slowck; + bool bypass; + int ret; + + if (!regbase) + return; + + slow_rc = at91_clk_register_slow_rc_osc(regbase, parent_names[0], + 32768, 50000000, + rc_osc_startup_us, bits); + if (IS_ERR(slow_rc)) + return; + + xtal_name = of_clk_get_parent_name(np, 0); + if (!xtal_name) { + /* DT backward compatibility */ + child = of_get_compatible_child(np, "atmel,at91sam9x5-clk-slow-osc"); + if (!child) + goto unregister_slow_rc; + + xtal_name = of_clk_get_parent_name(child, 0); + bypass = of_property_read_bool(child, "atmel,osc-bypass"); + + child = of_get_compatible_child(np, "atmel,at91sam9x5-clk-slow"); + } else { + bypass = of_property_read_bool(np, "atmel,osc-bypass"); + } + + if (!xtal_name) + goto unregister_slow_rc; + + slow_osc = at91_clk_register_slow_osc(regbase, parent_names[1], + xtal_name, 1200000, bypass, bits); + if (IS_ERR(slow_osc)) + goto unregister_slow_rc; + + slowck = at91_clk_register_sam9x5_slow(regbase, "slowck", parent_names, + 2, bits); + if (IS_ERR(slowck)) + goto unregister_slow_osc; + + /* DT backward compatibility */ + if (child) + ret = of_clk_add_hw_provider(child, of_clk_hw_simple_get, + slowck); + else + ret = of_clk_add_hw_provider(np, of_clk_hw_simple_get, slowck); + + if (WARN_ON(ret)) + goto unregister_slowck; + + return; + +unregister_slowck: + at91_clk_unregister_sam9x5_slow(slowck); +unregister_slow_osc: + at91_clk_unregister_slow_osc(slow_osc); +unregister_slow_rc: + at91_clk_unregister_slow_rc_osc(slow_rc); +} + +static const struct clk_slow_bits at91sam9x5_bits = { + .cr_rcen = BIT(0), + .cr_osc32en = BIT(1), + .cr_osc32byp = BIT(2), + .cr_oscsel = BIT(3), +}; + +static void __init of_at91sam9x5_sckc_setup(struct device_node *np) +{ + at91sam9x5_sckc_register(np, 75, &at91sam9x5_bits); +} +CLK_OF_DECLARE(at91sam9x5_clk_sckc, "atmel,at91sam9x5-sckc", + of_at91sam9x5_sckc_setup); + +static void __init of_sama5d3_sckc_setup(struct device_node *np) +{ + at91sam9x5_sckc_register(np, 500, &at91sam9x5_bits); +} +CLK_OF_DECLARE(sama5d3_clk_sckc, "atmel,sama5d3-sckc", + of_sama5d3_sckc_setup); + +static const struct clk_slow_bits at91sam9x60_bits = { + .cr_osc32en = BIT(1), + .cr_osc32byp = BIT(2), + .cr_oscsel = BIT(24), +}; + +static void __init of_sam9x60_sckc_setup(struct device_node *np) +{ + void __iomem *regbase = of_iomap(np, 0); + struct clk_hw_onecell_data *clk_data; + struct clk_hw *slow_rc, *slow_osc; + const char *xtal_name; + const char *parent_names[2] = { "slow_rc_osc", "slow_osc" }; + bool bypass; + int ret; + + if (!regbase) + return; + + slow_rc = clk_hw_register_fixed_rate_with_accuracy(NULL, parent_names[0], + NULL, 0, 32768, + 93750000); + if (IS_ERR(slow_rc)) + return; + + xtal_name = of_clk_get_parent_name(np, 0); + if (!xtal_name) + goto unregister_slow_rc; + + bypass = of_property_read_bool(np, "atmel,osc-bypass"); + slow_osc = at91_clk_register_slow_osc(regbase, parent_names[1], + xtal_name, 5000000, bypass, + &at91sam9x60_bits); + if (IS_ERR(slow_osc)) + goto unregister_slow_rc; + + clk_data = kzalloc(struct_size(clk_data, hws, 2), GFP_KERNEL); + if (!clk_data) + goto unregister_slow_osc; + + /* MD_SLCK and TD_SLCK. */ + clk_data->num = 2; + clk_data->hws[0] = clk_hw_register_fixed_rate(NULL, "md_slck", + parent_names[0], + 0, 32768); + if (IS_ERR(clk_data->hws[0])) + goto clk_data_free; + + clk_data->hws[1] = at91_clk_register_sam9x5_slow(regbase, "td_slck", + parent_names, 2, + &at91sam9x60_bits); + if (IS_ERR(clk_data->hws[1])) + goto unregister_md_slck; + + ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, clk_data); + if (WARN_ON(ret)) + goto unregister_td_slck; + + return; + +unregister_td_slck: + at91_clk_unregister_sam9x5_slow(clk_data->hws[1]); +unregister_md_slck: + clk_hw_unregister(clk_data->hws[0]); +clk_data_free: + kfree(clk_data); +unregister_slow_osc: + at91_clk_unregister_slow_osc(slow_osc); +unregister_slow_rc: + clk_hw_unregister(slow_rc); +} +CLK_OF_DECLARE(sam9x60_clk_sckc, "microchip,sam9x60-sckc", + of_sam9x60_sckc_setup); + +static int clk_sama5d4_slow_osc_prepare(struct clk_hw *hw) +{ + struct clk_sama5d4_slow_osc *osc = to_clk_sama5d4_slow_osc(hw); + + if (osc->prepared) + return 0; + + /* + * Assume that if it has already been selected (for example by the + * bootloader), enough time has already passed. + */ + if ((readl(osc->sckcr) & osc->bits->cr_oscsel)) { + osc->prepared = true; + return 0; + } + + if (system_state < SYSTEM_RUNNING) + udelay(osc->startup_usec); + else + usleep_range(osc->startup_usec, osc->startup_usec + 1); + osc->prepared = true; + + return 0; +} + +static int clk_sama5d4_slow_osc_is_prepared(struct clk_hw *hw) +{ + struct clk_sama5d4_slow_osc *osc = to_clk_sama5d4_slow_osc(hw); + + return osc->prepared; +} + +static const struct clk_ops sama5d4_slow_osc_ops = { + .prepare = clk_sama5d4_slow_osc_prepare, + .is_prepared = clk_sama5d4_slow_osc_is_prepared, +}; + +static const struct clk_slow_bits at91sama5d4_bits = { + .cr_oscsel = BIT(3), +}; + +static void __init of_sama5d4_sckc_setup(struct device_node *np) +{ + void __iomem *regbase = of_iomap(np, 0); + struct clk_hw *slow_rc, *slowck; + struct clk_sama5d4_slow_osc *osc; + struct clk_init_data init; + const char *xtal_name; + const char *parent_names[2] = { "slow_rc_osc", "slow_osc" }; + int ret; + + if (!regbase) + return; + + slow_rc = clk_hw_register_fixed_rate_with_accuracy(NULL, + parent_names[0], + NULL, 0, 32768, + 250000000); + if (IS_ERR(slow_rc)) + return; + + xtal_name = of_clk_get_parent_name(np, 0); + + osc = kzalloc(sizeof(*osc), GFP_KERNEL); + if (!osc) + goto unregister_slow_rc; + + init.name = parent_names[1]; + init.ops = &sama5d4_slow_osc_ops; + init.parent_names = &xtal_name; + init.num_parents = 1; + init.flags = CLK_IGNORE_UNUSED; + + osc->hw.init = &init; + osc->sckcr = regbase; + osc->startup_usec = 1200000; + osc->bits = &at91sama5d4_bits; + + ret = clk_hw_register(NULL, &osc->hw); + if (ret) + goto free_slow_osc_data; + + slowck = at91_clk_register_sam9x5_slow(regbase, "slowck", + parent_names, 2, + &at91sama5d4_bits); + if (IS_ERR(slowck)) + goto unregister_slow_osc; + + ret = of_clk_add_hw_provider(np, of_clk_hw_simple_get, slowck); + if (WARN_ON(ret)) + goto unregister_slowck; + + return; + +unregister_slowck: + at91_clk_unregister_sam9x5_slow(slowck); +unregister_slow_osc: + clk_hw_unregister(&osc->hw); +free_slow_osc_data: + kfree(osc); +unregister_slow_rc: + clk_hw_unregister(slow_rc); +} +CLK_OF_DECLARE(sama5d4_clk_sckc, "atmel,sama5d4-sckc", + of_sama5d4_sckc_setup); |