diff options
Diffstat (limited to 'drivers/clk/sifive/sifive-prci.c')
| -rw-r--r-- | drivers/clk/sifive/sifive-prci.c | 581 |
1 files changed, 581 insertions, 0 deletions
diff --git a/drivers/clk/sifive/sifive-prci.c b/drivers/clk/sifive/sifive-prci.c new file mode 100644 index 0000000000..b452bbf8cc --- /dev/null +++ b/drivers/clk/sifive/sifive-prci.c @@ -0,0 +1,581 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020 SiFive, Inc. + * Copyright (C) 2020 Zong Li + */ + +#include <common.h> +#include <linux/list.h> +#include <linux/clkdev.h> +#include <linux/overflow.h> +#include <printk.h> +#include <clock.h> +#include <io.h> +#include <of.h> +#include <driver.h> +#include <init.h> +#include "sifive-prci.h" +#include "fu540-prci.h" +#include "fu740-prci.h" + +static const struct prci_clk_desc prci_clk_fu540 = { + .clks = __prci_init_clocks_fu540, + .num_clks = ARRAY_SIZE(__prci_init_clocks_fu540), +}; + +/* + * Private functions + */ + +/** + * __prci_readl() - read from a PRCI register + * @pd: PRCI context + * @offs: register offset to read from (in bytes, from PRCI base address) + * + * Read the register located at offset @offs from the base virtual + * address of the PRCI register target described by @pd, and return + * the value to the caller. + * + * Context: Any context. + * + * Return: the contents of the register described by @pd and @offs. + */ +static u32 __prci_readl(struct __prci_data *pd, u32 offs) +{ + return readl(pd->va + offs); +} + +static void __prci_writel(u32 v, u32 offs, struct __prci_data *pd) +{ + writel(v, pd->va + offs); +} + +/* WRPLL-related private functions */ + +/** + * __prci_wrpll_unpack() - unpack WRPLL configuration registers into parameters + * @c: ptr to a struct wrpll_cfg record to write config into + * @r: value read from the PRCI PLL configuration register + * + * Given a value @r read from an FU740 PRCI PLL configuration register, + * split it into fields and populate it into the WRPLL configuration record + * pointed to by @c. + * + * The COREPLLCFG0 macros are used below, but the other *PLLCFG0 macros + * have the same register layout. + * + * Context: Any context. + */ +static void __prci_wrpll_unpack(struct wrpll_cfg *c, u32 r) +{ + u32 v; + + v = r & PRCI_COREPLLCFG0_DIVR_MASK; + v >>= PRCI_COREPLLCFG0_DIVR_SHIFT; + c->divr = v; + + v = r & PRCI_COREPLLCFG0_DIVF_MASK; + v >>= PRCI_COREPLLCFG0_DIVF_SHIFT; + c->divf = v; + + v = r & PRCI_COREPLLCFG0_DIVQ_MASK; + v >>= PRCI_COREPLLCFG0_DIVQ_SHIFT; + c->divq = v; + + v = r & PRCI_COREPLLCFG0_RANGE_MASK; + v >>= PRCI_COREPLLCFG0_RANGE_SHIFT; + c->range = v; + + c->flags &= + (WRPLL_FLAGS_INT_FEEDBACK_MASK | WRPLL_FLAGS_EXT_FEEDBACK_MASK); + + /* external feedback mode not supported */ + c->flags |= WRPLL_FLAGS_INT_FEEDBACK_MASK; +} + +/** + * __prci_wrpll_pack() - pack PLL configuration parameters into a register value + * @c: pointer to a struct wrpll_cfg record containing the PLL's cfg + * + * Using a set of WRPLL configuration values pointed to by @c, + * assemble a PRCI PLL configuration register value, and return it to + * the caller. + * + * Context: Any context. Caller must ensure that the contents of the + * record pointed to by @c do not change during the execution + * of this function. + * + * Returns: a value suitable for writing into a PRCI PLL configuration + * register + */ +static u32 __prci_wrpll_pack(const struct wrpll_cfg *c) +{ + u32 r = 0; + + r |= c->divr << PRCI_COREPLLCFG0_DIVR_SHIFT; + r |= c->divf << PRCI_COREPLLCFG0_DIVF_SHIFT; + r |= c->divq << PRCI_COREPLLCFG0_DIVQ_SHIFT; + r |= c->range << PRCI_COREPLLCFG0_RANGE_SHIFT; + + /* external feedback mode not supported */ + r |= PRCI_COREPLLCFG0_FSE_MASK; + + return r; +} + +/** + * __prci_wrpll_read_cfg0() - read the WRPLL configuration from the PRCI + * @pd: PRCI context + * @pwd: PRCI WRPLL metadata + * + * Read the current configuration of the PLL identified by @pwd from + * the PRCI identified by @pd, and store it into the local configuration + * cache in @pwd. + * + * Context: Any context. Caller must prevent the records pointed to by + * @pd and @pwd from changing during execution. + */ +static void __prci_wrpll_read_cfg0(struct __prci_data *pd, + struct __prci_wrpll_data *pwd) +{ + __prci_wrpll_unpack(&pwd->c, __prci_readl(pd, pwd->cfg0_offs)); +} + +/** + * __prci_wrpll_write_cfg0() - write WRPLL configuration into the PRCI + * @pd: PRCI context + * @pwd: PRCI WRPLL metadata + * @c: WRPLL configuration record to write + * + * Write the WRPLL configuration described by @c into the WRPLL + * configuration register identified by @pwd in the PRCI instance + * described by @c. Make a cached copy of the WRPLL's current + * configuration so it can be used by other code. + * + * Context: Any context. Caller must prevent the records pointed to by + * @pd and @pwd from changing during execution. + */ +static void __prci_wrpll_write_cfg0(struct __prci_data *pd, + struct __prci_wrpll_data *pwd, + struct wrpll_cfg *c) +{ + __prci_writel(__prci_wrpll_pack(c), pwd->cfg0_offs, pd); + + memcpy(&pwd->c, c, sizeof(*c)); +} + +/** + * __prci_wrpll_write_cfg1() - write Clock enable/disable configuration + * into the PRCI + * @pd: PRCI context + * @pwd: PRCI WRPLL metadata + * @enable: Clock enable or disable value + */ +static void __prci_wrpll_write_cfg1(struct __prci_data *pd, + struct __prci_wrpll_data *pwd, + u32 enable) +{ + __prci_writel(enable, pwd->cfg1_offs, pd); +} + +/* + * Linux clock framework integration + * + * See the Linux clock framework documentation for more information on + * these functions. + */ + +unsigned long sifive_prci_wrpll_recalc_rate(struct clk *hw, + unsigned long parent_rate) +{ + struct __prci_clock *pc = clk_hw_to_prci_clock(hw); + struct __prci_wrpll_data *pwd = pc->pwd; + + return wrpll_calc_output_rate(&pwd->c, parent_rate); +} + +long sifive_prci_wrpll_round_rate(struct clk *hw, + unsigned long rate, + unsigned long *parent_rate) +{ + struct __prci_clock *pc = clk_hw_to_prci_clock(hw); + struct __prci_wrpll_data *pwd = pc->pwd; + struct wrpll_cfg c; + + memcpy(&c, &pwd->c, sizeof(c)); + + wrpll_configure_for_rate(&c, rate, *parent_rate); + + return wrpll_calc_output_rate(&c, *parent_rate); +} + +int sifive_prci_wrpll_set_rate(struct clk *hw, + unsigned long rate, unsigned long parent_rate) +{ + struct __prci_clock *pc = clk_hw_to_prci_clock(hw); + struct __prci_wrpll_data *pwd = pc->pwd; + struct __prci_data *pd = pc->pd; + int r; + + r = wrpll_configure_for_rate(&pwd->c, rate, parent_rate); + if (r) + return r; + + if (pwd->enable_bypass) + pwd->enable_bypass(pd); + + __prci_wrpll_write_cfg0(pd, pwd, &pwd->c); + + udelay(wrpll_calc_max_lock_us(&pwd->c)); + + return 0; +} + +int sifive_clk_is_enabled(struct clk *hw) +{ + struct __prci_clock *pc = clk_hw_to_prci_clock(hw); + struct __prci_wrpll_data *pwd = pc->pwd; + struct __prci_data *pd = pc->pd; + u32 r; + + r = __prci_readl(pd, pwd->cfg1_offs); + + if (r & PRCI_COREPLLCFG1_CKE_MASK) + return 1; + else + return 0; +} + +int sifive_prci_clock_enable(struct clk *hw) +{ + struct __prci_clock *pc = clk_hw_to_prci_clock(hw); + struct __prci_wrpll_data *pwd = pc->pwd; + struct __prci_data *pd = pc->pd; + + if (sifive_clk_is_enabled(hw)) + return 0; + + __prci_wrpll_write_cfg1(pd, pwd, PRCI_COREPLLCFG1_CKE_MASK); + + if (pwd->disable_bypass) + pwd->disable_bypass(pd); + + return 0; +} + +void sifive_prci_clock_disable(struct clk *hw) +{ + struct __prci_clock *pc = clk_hw_to_prci_clock(hw); + struct __prci_wrpll_data *pwd = pc->pwd; + struct __prci_data *pd = pc->pd; + u32 r; + + if (pwd->enable_bypass) + pwd->enable_bypass(pd); + + r = __prci_readl(pd, pwd->cfg1_offs); + r &= ~PRCI_COREPLLCFG1_CKE_MASK; + + __prci_wrpll_write_cfg1(pd, pwd, r); +} + +/* TLCLKSEL clock integration */ + +unsigned long sifive_prci_tlclksel_recalc_rate(struct clk *hw, + unsigned long parent_rate) +{ + struct __prci_clock *pc = clk_hw_to_prci_clock(hw); + struct __prci_data *pd = pc->pd; + u32 v; + u8 div; + + v = __prci_readl(pd, PRCI_CLKMUXSTATUSREG_OFFSET); + v &= PRCI_CLKMUXSTATUSREG_TLCLKSEL_STATUS_MASK; + div = v ? 1 : 2; + + return div_u64(parent_rate, div); +} + +/* HFPCLK clock integration */ + +unsigned long sifive_prci_hfpclkplldiv_recalc_rate(struct clk *hw, + unsigned long parent_rate) +{ + struct __prci_clock *pc = clk_hw_to_prci_clock(hw); + struct __prci_data *pd = pc->pd; + u32 div = __prci_readl(pd, PRCI_HFPCLKPLLDIV_OFFSET); + + return div_u64(parent_rate, div + 2); +} + +/* + * Core clock mux control + */ + +/** + * sifive_prci_coreclksel_use_hfclk() - switch the CORECLK mux to output HFCLK + * @pd: struct __prci_data * for the PRCI containing the CORECLK mux reg + * + * Switch the CORECLK mux to the HFCLK input source; return once complete. + * + * Context: Any context. Caller must prevent concurrent changes to the + * PRCI_CORECLKSEL_OFFSET register. + */ +void sifive_prci_coreclksel_use_hfclk(struct __prci_data *pd) +{ + u32 r; + + r = __prci_readl(pd, PRCI_CORECLKSEL_OFFSET); + r |= PRCI_CORECLKSEL_CORECLKSEL_MASK; + __prci_writel(r, PRCI_CORECLKSEL_OFFSET, pd); + + r = __prci_readl(pd, PRCI_CORECLKSEL_OFFSET); /* barrier */ +} + +/** + * sifive_prci_coreclksel_use_corepll() - switch the CORECLK mux to output + * COREPLL + * @pd: struct __prci_data * for the PRCI containing the CORECLK mux reg + * + * Switch the CORECLK mux to the COREPLL output clock; return once complete. + * + * Context: Any context. Caller must prevent concurrent changes to the + * PRCI_CORECLKSEL_OFFSET register. + */ +void sifive_prci_coreclksel_use_corepll(struct __prci_data *pd) +{ + u32 r; + + r = __prci_readl(pd, PRCI_CORECLKSEL_OFFSET); + r &= ~PRCI_CORECLKSEL_CORECLKSEL_MASK; + __prci_writel(r, PRCI_CORECLKSEL_OFFSET, pd); + + r = __prci_readl(pd, PRCI_CORECLKSEL_OFFSET); /* barrier */ +} + +/** + * sifive_prci_coreclksel_use_final_corepll() - switch the CORECLK mux to output + * FINAL_COREPLL + * @pd: struct __prci_data * for the PRCI containing the CORECLK mux reg + * + * Switch the CORECLK mux to the final COREPLL output clock; return once + * complete. + * + * Context: Any context. Caller must prevent concurrent changes to the + * PRCI_CORECLKSEL_OFFSET register. + */ +void sifive_prci_coreclksel_use_final_corepll(struct __prci_data *pd) +{ + u32 r; + + r = __prci_readl(pd, PRCI_CORECLKSEL_OFFSET); + r &= ~PRCI_CORECLKSEL_CORECLKSEL_MASK; + __prci_writel(r, PRCI_CORECLKSEL_OFFSET, pd); + + r = __prci_readl(pd, PRCI_CORECLKSEL_OFFSET); /* barrier */ +} + +/** + * sifive_prci_corepllsel_use_dvfscorepll() - switch the COREPLL mux to + * output DVFS_COREPLL + * @pd: struct __prci_data * for the PRCI containing the COREPLL mux reg + * + * Switch the COREPLL mux to the DVFSCOREPLL output clock; return once complete. + * + * Context: Any context. Caller must prevent concurrent changes to the + * PRCI_COREPLLSEL_OFFSET register. + */ +void sifive_prci_corepllsel_use_dvfscorepll(struct __prci_data *pd) +{ + u32 r; + + r = __prci_readl(pd, PRCI_COREPLLSEL_OFFSET); + r |= PRCI_COREPLLSEL_COREPLLSEL_MASK; + __prci_writel(r, PRCI_COREPLLSEL_OFFSET, pd); + + r = __prci_readl(pd, PRCI_COREPLLSEL_OFFSET); /* barrier */ +} + +/** + * sifive_prci_corepllsel_use_corepll() - switch the COREPLL mux to + * output COREPLL + * @pd: struct __prci_data * for the PRCI containing the COREPLL mux reg + * + * Switch the COREPLL mux to the COREPLL output clock; return once complete. + * + * Context: Any context. Caller must prevent concurrent changes to the + * PRCI_COREPLLSEL_OFFSET register. + */ +void sifive_prci_corepllsel_use_corepll(struct __prci_data *pd) +{ + u32 r; + + r = __prci_readl(pd, PRCI_COREPLLSEL_OFFSET); + r &= ~PRCI_COREPLLSEL_COREPLLSEL_MASK; + __prci_writel(r, PRCI_COREPLLSEL_OFFSET, pd); + + r = __prci_readl(pd, PRCI_COREPLLSEL_OFFSET); /* barrier */ +} + +/** + * sifive_prci_hfpclkpllsel_use_hfclk() - switch the HFPCLKPLL mux to + * output HFCLK + * @pd: struct __prci_data * for the PRCI containing the HFPCLKPLL mux reg + * + * Switch the HFPCLKPLL mux to the HFCLK input source; return once complete. + * + * Context: Any context. Caller must prevent concurrent changes to the + * PRCI_HFPCLKPLLSEL_OFFSET register. + */ +void sifive_prci_hfpclkpllsel_use_hfclk(struct __prci_data *pd) +{ + u32 r; + + r = __prci_readl(pd, PRCI_HFPCLKPLLSEL_OFFSET); + r |= PRCI_HFPCLKPLLSEL_HFPCLKPLLSEL_MASK; + __prci_writel(r, PRCI_HFPCLKPLLSEL_OFFSET, pd); + + r = __prci_readl(pd, PRCI_HFPCLKPLLSEL_OFFSET); /* barrier */ +} + +/** + * sifive_prci_hfpclkpllsel_use_hfpclkpll() - switch the HFPCLKPLL mux to + * output HFPCLKPLL + * @pd: struct __prci_data * for the PRCI containing the HFPCLKPLL mux reg + * + * Switch the HFPCLKPLL mux to the HFPCLKPLL output clock; return once complete. + * + * Context: Any context. Caller must prevent concurrent changes to the + * PRCI_HFPCLKPLLSEL_OFFSET register. + */ +void sifive_prci_hfpclkpllsel_use_hfpclkpll(struct __prci_data *pd) +{ + u32 r; + + r = __prci_readl(pd, PRCI_HFPCLKPLLSEL_OFFSET); + r &= ~PRCI_HFPCLKPLLSEL_HFPCLKPLLSEL_MASK; + __prci_writel(r, PRCI_HFPCLKPLLSEL_OFFSET, pd); + + r = __prci_readl(pd, PRCI_HFPCLKPLLSEL_OFFSET); /* barrier */ +} + +/** + * __prci_register_clocks() - register clock controls in the PRCI + * @dev: Linux struct device + * @pd: The pointer for PRCI per-device instance data + * @desc: The pointer for the information of clocks of each SoCs + * + * Register the list of clock controls described in __prci_init_clocks[] with + * the Linux clock framework. + * + * Return: 0 upon success or a negative error code upon failure. + */ +static int __prci_register_clocks(struct device_d *dev, struct __prci_data *pd, + const struct prci_clk_desc *desc) +{ + struct __prci_clock *pic; + int parent_count, i, r; + + parent_count = of_clk_get_parent_count(dev->device_node); + if (parent_count != EXPECTED_CLK_PARENT_COUNT) { + dev_err(dev, "expected only two parent clocks, found %d\n", + parent_count); + return -EINVAL; + } + + /* Register PLLs */ + for (i = 0; i < desc->num_clks; ++i) { + pic = &(desc->clks[i]); + + pic->hw.name = pic->name; + pic->hw.parent_names = &pic->parent_name; + pic->hw.num_parents = 1; + pic->hw.ops = pic->ops; + + pic->pd = pd; + + if (pic->pwd) + __prci_wrpll_read_cfg0(pd, pic->pwd); + + r = clk_register(&pic->hw); + if (r) { + dev_warn(dev, "Failed to register clock %s: %d\n", + pic->hw.name, r); + return r; + } + + r = clk_register_clkdev(&pic->hw, pic->name, dev_name(dev)); + if (r) { + dev_warn(dev, "Failed to register clkdev for %s: %d\n", + pic->hw.name, r); + return r; + } + + pd->hw_clks.clks[i] = &pic->hw; + } + + pd->hw_clks.clk_num = i; + + r = of_clk_add_provider(dev->device_node, of_clk_src_onecell_get, + &pd->hw_clks); + if (r) { + dev_err(dev, "could not add hw_provider: %d\n", r); + return r; + } + + return 0; +} + +/** + * sifive_prci_init() - initialize prci data and check parent count + * @dev: platform device pointer for the prci + * + * Return: 0 upon success or a negative error code upon failure. + */ +static int sifive_prci_probe(struct device_d *dev) +{ + struct resource *res; + struct __prci_data *pd; + const struct prci_clk_desc *desc; + int r; + + desc = device_get_match_data(dev); + + pd = malloc(sizeof(*pd)); + if (!pd) + return -ENOMEM; + + pd->hw_clks.clk_num = desc->num_clks; + pd->hw_clks.clks = calloc(pd->hw_clks.clk_num, sizeof(*pd->hw_clks.clks)); + if (!pd->hw_clks.clks) + return -ENOMEM; + + res = dev_request_mem_resource(dev, 0); + if (IS_ERR(res)) + return PTR_ERR(res); + + pd->va = IOMEM(res->start); + + r = __prci_register_clocks(dev, pd, desc); + if (r) { + dev_err(dev, "could not register clocks: %d\n", r); + return r; + } + + dev_dbg(dev, "SiFive PRCI probed\n"); + + return 0; +} + +static const struct of_device_id sifive_prci_of_match[] = { + {.compatible = "sifive,fu540-c000-prci", .data = &prci_clk_fu540}, + {.compatible = "sifive,fu740-c000-prci", .data = &prci_clk_fu740}, + {} +}; + +static struct driver_d sifive_prci_driver = { + .name = "sifive-clk-prci", + .of_compatible = sifive_prci_of_match, + .probe = sifive_prci_probe, +}; +core_platform_driver(sifive_prci_driver); |