Add clk-main driver compatible with common clock framework.
Signed-off-by: Claudiu Beznea claudiu.beznea@microchip.com --- drivers/clk/at91/Makefile | 2 +- drivers/clk/at91/clk-main.c | 387 ++++++++++++++++++++++++++++++++++++++++++++ drivers/clk/at91/pmc.h | 10 ++ 3 files changed, 398 insertions(+), 1 deletion(-) create mode 100644 drivers/clk/at91/clk-main.c
diff --git a/drivers/clk/at91/Makefile b/drivers/clk/at91/Makefile index 7083ce2890d6..805f67677a9b 100644 --- a/drivers/clk/at91/Makefile +++ b/drivers/clk/at91/Makefile @@ -3,7 +3,7 @@ #
ifdef CONFIG_CLK_CCF -obj-y += pmc.o sckc.o +obj-y += pmc.o sckc.o clk-main.o else obj-y += compat.o endif diff --git a/drivers/clk/at91/clk-main.c b/drivers/clk/at91/clk-main.c new file mode 100644 index 000000000000..b52d926f3390 --- /dev/null +++ b/drivers/clk/at91/clk-main.c @@ -0,0 +1,387 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Main clock support for AT91 architectures. + * + * Copyright (C) 2020 Microchip Technology Inc. and its subsidiaries + * + * Author: Claudiu Beznea claudiu.beznea@microchip.com + * + * Based on drivers/clk/at91/clk-main.c from Linux. + */ + +#include <asm/processor.h> +#include <common.h> +#include <clk-uclass.h> +#include <dm.h> +#include <linux/clk-provider.h> +#include <linux/clk/at91_pmc.h> +#include <linux/delay.h> +#include <linux/io.h> +#include "pmc.h" + +#define UBOOT_DM_CLK_AT91_MAIN_RC "at91-main-rc-clk" +#define UBOOT_DM_CLK_AT91_MAIN_OSC "at91-main-osc-clk" +#define UBOOT_DM_CLK_AT91_RM9200_MAIN "at91-rm9200-main-clk" +#define UBOOT_DM_CLK_AT91_SAM9X5_MAIN "at91-sam9x5-main-clk" + +#define MOR_KEY_MASK GENMASK(23, 16) +#define USEC_PER_SEC 1000000UL +#define SLOW_CLOCK_FREQ 32768 + +#define clk_main_parent_select(s) (((s) & \ + (AT91_PMC_MOSCEN | \ + AT91_PMC_OSCBYPASS)) ? 1 : 0) + +struct clk_main_rc { + void __iomem *reg; + struct clk clk; +}; + +#define to_clk_main_rc(_clk) container_of(_clk, struct clk_main_rc, clk) + +struct clk_main_osc { + void __iomem *reg; + struct clk clk; +}; + +#define to_clk_main_osc(_clk) container_of(_clk, struct clk_main_osc, clk) + +struct clk_main { + void __iomem *reg; + const unsigned int *clk_mux_table; + const char * const *parent_names; + unsigned int num_parents; + int type; + struct clk clk; +}; + +#define to_clk_main(_clk) container_of(_clk, struct clk_main, clk) + +static int main_rc_enable(struct clk *clk) +{ + struct clk_main_rc *main_rc = to_clk_main_rc(clk); + void __iomem *reg = main_rc->reg; + unsigned int val; + + pmc_read(reg, AT91_CKGR_MOR, &val); + + if (!(val & AT91_PMC_MOSCRCEN)) { + pmc_update_bits(reg, AT91_CKGR_MOR, + MOR_KEY_MASK | AT91_PMC_MOSCRCEN, + AT91_PMC_KEY | AT91_PMC_MOSCRCEN); + } + + pmc_read(reg, AT91_PMC_SR, &val); + while (!(val & AT91_PMC_MOSCRCS)) { + pmc_read(reg, AT91_PMC_SR, &val); + debug("waiting for main rc...\n"); + cpu_relax(); + } + + return 0; +} + +static int main_rc_disable(struct clk *clk) +{ + struct clk_main_rc *main_rc = to_clk_main_rc(clk); + struct reg *reg = main_rc->reg; + unsigned int val; + + pmc_read(reg, AT91_CKGR_MOR, &val); + + if (!(val & AT91_PMC_MOSCRCEN)) + return 0; + + pmc_update_bits(reg, AT91_CKGR_MOR, MOR_KEY_MASK | AT91_PMC_MOSCRCEN, + AT91_PMC_KEY); + + return 0; +} + +static const struct clk_ops main_rc_clk_ops = { + .enable = main_rc_enable, + .disable = main_rc_disable, + .get_rate = clk_generic_get_rate, +}; + +struct clk *at91_clk_main_rc(void __iomem *reg, const char *name, + const char *parent_name) +{ + struct clk_main_rc *main_rc; + struct clk *clk; + int ret; + + if (!reg || !name || !parent_name) + return ERR_PTR(-EINVAL); + + main_rc = kzalloc(sizeof(*main_rc), GFP_KERNEL); + if (!main_rc) + return ERR_PTR(-ENOMEM); + + main_rc->reg = reg; + clk = &main_rc->clk; + + ret = clk_register(clk, UBOOT_DM_CLK_AT91_MAIN_RC, name, + parent_name); + if (ret) { + kfree(main_rc); + clk = ERR_PTR(ret); + } + + return clk; +} + +U_BOOT_DRIVER(at91_main_rc_clk) = { + .name = UBOOT_DM_CLK_AT91_MAIN_RC, + .id = UCLASS_CLK, + .ops = &main_rc_clk_ops, + .flags = DM_FLAG_PRE_RELOC, +}; + +static int clk_main_osc_enable(struct clk *clk) +{ + struct clk_main_osc *main = to_clk_main_osc(clk); + void __iomem *reg = main->reg; + unsigned int val; + + pmc_read(reg, AT91_CKGR_MOR, &val); + val &= ~MOR_KEY_MASK; + + if (val & AT91_PMC_OSCBYPASS) + return 0; + + if (!(val & AT91_PMC_MOSCEN)) { + val |= AT91_PMC_MOSCEN | AT91_PMC_KEY; + pmc_write(reg, AT91_CKGR_MOR, val); + } + + pmc_read(reg, AT91_PMC_SR, &val); + while (!(val & AT91_PMC_MOSCS)) { + pmc_read(reg, AT91_PMC_SR, &val); + debug("waiting for main osc..\n"); + cpu_relax(); + } + + return 0; +} + +static int clk_main_osc_disable(struct clk *clk) +{ + struct clk_main_osc *main = to_clk_main_osc(clk); + void __iomem *reg = main->reg; + unsigned int val; + + pmc_read(reg, AT91_CKGR_MOR, &val); + if (val & AT91_PMC_OSCBYPASS) + return 0; + + if (!(val & AT91_PMC_MOSCEN)) + return 0; + + val &= ~(AT91_PMC_KEY | AT91_PMC_MOSCEN); + pmc_write(reg, AT91_CKGR_MOR, val | AT91_PMC_KEY); + + return 0; +} + +static const struct clk_ops main_osc_clk_ops = { + .enable = clk_main_osc_enable, + .disable = clk_main_osc_disable, + .get_rate = clk_generic_get_rate, +}; + +struct clk *at91_clk_main_osc(void __iomem *reg, const char *name, + const char *parent_name, bool bypass) +{ + struct clk_main_osc *main; + struct clk *clk; + int ret; + + if (!reg || !name || !parent_name) + return ERR_PTR(-EINVAL); + + main = kzalloc(sizeof(*main), GFP_KERNEL); + if (!main) + return ERR_PTR(-ENOMEM); + + main->reg = reg; + clk = &main->clk; + + if (bypass) { + pmc_update_bits(reg, AT91_CKGR_MOR, + MOR_KEY_MASK | AT91_PMC_OSCBYPASS, + AT91_PMC_KEY | AT91_PMC_OSCBYPASS); + } + + ret = clk_register(clk, UBOOT_DM_CLK_AT91_MAIN_OSC, name, parent_name); + if (ret) { + kfree(main); + clk = ERR_PTR(ret); + } + + return clk; +} + +U_BOOT_DRIVER(at91_main_osc_clk) = { + .name = UBOOT_DM_CLK_AT91_MAIN_OSC, + .id = UCLASS_CLK, + .ops = &main_osc_clk_ops, + .flags = DM_FLAG_PRE_RELOC, +}; + +static int clk_main_probe_frequency(void __iomem *reg) +{ + unsigned int cycles = 16; + unsigned int cycle = DIV_ROUND_UP(USEC_PER_SEC, SLOW_CLOCK_FREQ); + unsigned int mcfr; + + while (cycles--) { + pmc_read(reg, AT91_CKGR_MCFR, &mcfr); + if (mcfr & AT91_PMC_MAINRDY) + return 0; + udelay(cycle); + } + + return -ETIMEDOUT; +} + +static int clk_rm9200_main_enable(struct clk *clk) +{ + struct clk_main *main = to_clk_main(clk); + + return clk_main_probe_frequency(main->reg); +} + +static const struct clk_ops rm9200_main_clk_ops = { + .enable = clk_rm9200_main_enable, +}; + +struct clk *at91_clk_rm9200_main(void __iomem *reg, const char *name, + const char *parent_name) +{ + struct clk_main *main; + struct clk *clk; + int ret; + + if (!reg || !name || !parent_name) + return ERR_PTR(-EINVAL); + + main = kzalloc(sizeof(*main), GFP_KERNEL); + if (!main) + return ERR_PTR(-ENOMEM); + + main->reg = reg; + clk = &main->clk; + + ret = clk_register(clk, UBOOT_DM_CLK_AT91_RM9200_MAIN, name, + parent_name); + if (ret) { + kfree(main); + clk = ERR_PTR(ret); + } + + return clk; +} + +U_BOOT_DRIVER(at91_rm9200_main_clk) = { + .name = UBOOT_DM_CLK_AT91_RM9200_MAIN, + .id = UCLASS_CLK, + .ops = &rm9200_main_clk_ops, + .flags = DM_FLAG_PRE_RELOC, +}; + +static inline bool clk_sam9x5_main_ready(void __iomem *reg) +{ + unsigned int val; + + pmc_read(reg, AT91_PMC_SR, &val); + + return !!(val & AT91_PMC_MOSCSELS); +} + +static int clk_sam9x5_main_enable(struct clk *clk) +{ + struct clk_main *main = to_clk_main(clk); + void __iomem *reg = main->reg; + + while (!clk_sam9x5_main_ready(reg)) { + debug("waiting for main..."); + cpu_relax(); + } + + return clk_main_probe_frequency(reg); +} + +static int clk_sam9x5_main_set_parent(struct clk *clk, struct clk *parent) +{ + struct clk_main *main = to_clk_main(clk); + void __iomem *reg = main->reg; + unsigned int tmp, index; + + index = at91_clk_mux_val_to_index(main->clk_mux_table, + main->num_parents, AT91_CLK_ID_TO_DID(parent->id)); + if (index < 0) + return index; + + pmc_read(reg, AT91_CKGR_MOR, &tmp); + tmp &= ~MOR_KEY_MASK; + tmp |= AT91_PMC_KEY; + + if (index && !(tmp & AT91_PMC_MOSCSEL)) + pmc_write(reg, AT91_CKGR_MOR, tmp | AT91_PMC_MOSCSEL); + else if (!index && (tmp & AT91_PMC_MOSCSEL)) + pmc_write(reg, AT91_CKGR_MOR, tmp & ~AT91_PMC_MOSCSEL); + + while (!clk_sam9x5_main_ready(reg)) + cpu_relax(); + + return 0; +} + +static const struct clk_ops sam9x5_main_clk_ops = { + .enable = clk_sam9x5_main_enable, + .set_parent = clk_sam9x5_main_set_parent, + .get_rate = clk_generic_get_rate, +}; + +struct clk *at91_clk_sam9x5_main(void __iomem *reg, const char *name, + const char * const *parent_names, + int num_parents, const u32 *clk_mux_table, + int type) +{ + struct clk *clk = ERR_PTR(-ENOMEM); + struct clk_main *main = NULL; + unsigned int val; + int ret; + + if (!reg || !name || !parent_names || !num_parents || !clk_mux_table) + return ERR_PTR(-EINVAL); + + main = kzalloc(sizeof(*main), GFP_KERNEL); + if (!main) + return ERR_PTR(-ENOMEM); + + main->reg = reg; + main->parent_names = parent_names; + main->num_parents = num_parents; + main->clk_mux_table = clk_mux_table; + main->type = type; + clk = &main->clk; + clk->flags = CLK_GET_RATE_NOCACHE; + pmc_read(reg, AT91_CKGR_MOR, &val); + ret = clk_register(clk, UBOOT_DM_CLK_AT91_SAM9X5_MAIN, name, + main->parent_names[clk_main_parent_select(val)]); + if (ret) { + kfree(main); + clk = ERR_PTR(ret); + } + + return clk; +} + +U_BOOT_DRIVER(at91_sam9x5_main_clk) = { + .name = UBOOT_DM_CLK_AT91_SAM9X5_MAIN, + .id = UCLASS_CLK, + .ops = &sam9x5_main_clk_ops, + .flags = DM_FLAG_PRE_RELOC, +}; diff --git a/drivers/clk/at91/pmc.h b/drivers/clk/at91/pmc.h index 33ded02156c8..62bfc4b3054c 100644 --- a/drivers/clk/at91/pmc.h +++ b/drivers/clk/at91/pmc.h @@ -14,6 +14,16 @@ #define AT91_TO_CLK_ID(_t, _i) (((_t) << 8) | ((_i) & 0xff)) #define AT91_CLK_ID_TO_DID(_i) ((_i) & 0xff)
+struct clk *at91_clk_main_rc(void __iomem *reg, const char *name, + const char *parent_name); +struct clk *at91_clk_main_osc(void __iomem *reg, const char *name, + const char *parent_name, bool bypass); +struct clk *at91_clk_rm9200_main(void __iomem *reg, const char *name, + const char *parent_name); +struct clk *at91_clk_sam9x5_main(void __iomem *reg, const char *name, + const char * const *parent_names, int num_parents, + const u32 *mux_table, int type); + int at91_clk_mux_val_to_index(const u32 *table, u32 num_parents, u32 val); int at91_clk_mux_index_to_val(const u32 *table, u32 num_parents, u32 index);