From e9885aa7cc23c21f1fa254c7c8cc459eca67db84 Mon Sep 17 00:00:00 2001 From: Claudiu Beznea Date: Mon, 7 Sep 2020 17:46:40 +0300 Subject: clk: at91: sckc: add driver compatible with ccf Add sckc driver compatible with common clock framework. Driver implements slow clock support for SAM9X60 compatible IPs (in this list it is also present SAMA7G5's slow clock IP). Signed-off-by: Claudiu Beznea --- drivers/clk/at91/Makefile | 2 +- drivers/clk/at91/sckc.c | 172 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 173 insertions(+), 1 deletion(-) create mode 100644 drivers/clk/at91/sckc.c (limited to 'drivers/clk') diff --git a/drivers/clk/at91/Makefile b/drivers/clk/at91/Makefile index e2413af403..7083ce2890 100644 --- a/drivers/clk/at91/Makefile +++ b/drivers/clk/at91/Makefile @@ -3,7 +3,7 @@ # ifdef CONFIG_CLK_CCF -obj-y += pmc.o +obj-y += pmc.o sckc.o else obj-y += compat.o endif diff --git a/drivers/clk/at91/sckc.c b/drivers/clk/at91/sckc.c new file mode 100644 index 0000000000..dd62dc5510 --- /dev/null +++ b/drivers/clk/at91/sckc.c @@ -0,0 +1,172 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Slow clock support for AT91 architectures. + * + * Copyright (C) 2020 Microchip Technology Inc. and its subsidiaries + * + * Author: Claudiu Beznea + */ + +#include +#include +#include +#include +#include + +#include "pmc.h" + +#define UBOOT_DM_CLK_AT91_SAM9X60_TD_SLCK "at91-sam9x60-td-slck" +#define UBOOT_DM_CLK_AT91_SCKC "at91-sckc" + +#define AT91_OSC_SEL BIT(24) +#define AT91_OSC_SEL_SHIFT (24) + +struct sam9x60_sckc { + void __iomem *reg; + const char **parent_names; + unsigned int num_parents; + struct clk clk; +}; + +#define to_sam9x60_sckc(c) container_of(c, struct sam9x60_sckc, clk) + +static int sam9x60_sckc_of_xlate(struct clk *clk, + struct ofnode_phandle_args *args) +{ + if (args->args_count != 1) { + debug("AT91: SCKC: Invalid args_count: %d\n", args->args_count); + return -EINVAL; + } + + clk->id = AT91_TO_CLK_ID(PMC_TYPE_SLOW, args->args[0]); + + return 0; +} + +static const struct clk_ops sam9x60_sckc_ops = { + .of_xlate = sam9x60_sckc_of_xlate, + .get_rate = clk_generic_get_rate, +}; + +static int sam9x60_td_slck_set_parent(struct clk *clk, struct clk *parent) +{ + struct sam9x60_sckc *sckc = to_sam9x60_sckc(clk); + u32 i; + + for (i = 0; i < sckc->num_parents; i++) { + if (!strcmp(parent->dev->name, sckc->parent_names[i])) + break; + } + if (i == sckc->num_parents) + return -EINVAL; + + pmc_update_bits(sckc->reg, 0, AT91_OSC_SEL, (i << AT91_OSC_SEL_SHIFT)); + + return 0; +} + +static const struct clk_ops sam9x60_td_slck_ops = { + .get_rate = clk_generic_get_rate, + .set_parent = sam9x60_td_slck_set_parent, +}; + +static struct clk *at91_sam9x60_clk_register_td_slck(struct sam9x60_sckc *sckc, + const char *name, const char * const *parent_names, + int num_parents) +{ + struct clk *clk; + int ret = -ENOMEM; + u32 val, i; + + if (!sckc || !name || !parent_names || num_parents != 2) + return ERR_PTR(-EINVAL); + + sckc->parent_names = kzalloc(sizeof(*sckc->parent_names) * num_parents, + GFP_KERNEL); + if (!sckc->parent_names) + return ERR_PTR(ret); + + for (i = 0; i < num_parents; i++) { + sckc->parent_names[i] = kmemdup(parent_names[i], + strlen(parent_names[i]) + 1, GFP_KERNEL); + if (!sckc->parent_names[i]) + goto free; + } + sckc->num_parents = num_parents; + + pmc_read(sckc->reg, 0, &val); + val = (val & AT91_OSC_SEL) >> AT91_OSC_SEL_SHIFT; + + clk = &sckc->clk; + ret = clk_register(clk, UBOOT_DM_CLK_AT91_SAM9X60_TD_SLCK, name, + parent_names[val]); + if (ret) + goto free; + + return clk; + +free: + for (; i >= 0; i--) + kfree(sckc->parent_names[i]); + kfree(sckc->parent_names); + + return ERR_PTR(ret); +} + +U_BOOT_DRIVER(at91_sam9x60_td_slck) = { + .name = UBOOT_DM_CLK_AT91_SAM9X60_TD_SLCK, + .id = UCLASS_CLK, + .ops = &sam9x60_td_slck_ops, + .flags = DM_FLAG_PRE_RELOC, +}; + +static int at91_sam9x60_sckc_probe(struct udevice *dev) +{ + struct sam9x60_sckc *sckc = dev_get_priv(dev); + void __iomem *base = (void *)devfdt_get_addr(dev); + const char *slow_rc_osc, *slow_osc; + const char *parents[2]; + struct clk *clk, c; + int ret; + + ret = clk_get_by_index(dev, 0, &c); + if (ret) + return ret; + slow_rc_osc = clk_hw_get_name(&c); + + ret = clk_get_by_index(dev, 1, &c); + if (ret) + return ret; + slow_osc = clk_hw_get_name(&c); + + clk = clk_register_fixed_factor(NULL, "md_slck", slow_rc_osc, 0, 1, 1); + if (IS_ERR(clk)) + return PTR_ERR(clk); + clk_dm(AT91_TO_CLK_ID(PMC_TYPE_SLOW, 0), clk); + + parents[0] = slow_rc_osc; + parents[1] = slow_osc; + sckc[1].reg = base; + clk = at91_sam9x60_clk_register_td_slck(&sckc[1], "td_slck", + parents, 2); + if (IS_ERR(clk)) + return PTR_ERR(clk); + clk_dm(AT91_TO_CLK_ID(PMC_TYPE_SLOW, 1), clk); + + return 0; +} + +static const struct udevice_id sam9x60_sckc_ids[] = { + { .compatible = "microchip,sam9x60-sckc" }, + { /* Sentinel. */ }, +}; + +U_BOOT_DRIVER(at91_sckc) = { + .name = UBOOT_DM_CLK_AT91_SCKC, + .id = UCLASS_CLK, + .of_match = sam9x60_sckc_ids, + .priv_auto_alloc_size = sizeof(struct sam9x60_sckc) * 2, + .ops = &sam9x60_sckc_ops, + .probe = at91_sam9x60_sckc_probe, + .flags = DM_FLAG_PRE_RELOC, +}; -- cgit v1.2.3