// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2018-2021 SiFive, Inc. * Wesley Terpstra * Paul Walmsley * Zong Li * Pragnesh Patel * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * The PRCI implements clock and reset control for the SiFive chip. * This driver assumes that it has sole control over all PRCI resources. * * This driver is based on the PRCI driver written by Wesley Terpstra: * https://github.com/riscv/riscv-linux/commit/999529edf517ed75b56659d456d221b2ee56bb60 */ #include #include #include #include #include #include #include #include #include #include #include #include "fu540-prci.h" #include "fu740-prci.h" /* * 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 FU540 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); } unsigned long sifive_prci_wrpll_recalc_rate(struct __prci_clock *pc, unsigned long parent_rate) { struct __prci_wrpll_data *pwd = pc->pwd; return wrpll_calc_output_rate(&pwd->c, parent_rate); } unsigned long sifive_prci_wrpll_round_rate(struct __prci_clock *pc, unsigned long rate, unsigned long *parent_rate) { 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 __prci_clock *pc, unsigned long rate, unsigned long parent_rate) { 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_prci_clock_enable(struct __prci_clock *pc, bool enable) { struct __prci_wrpll_data *pwd = pc->pwd; struct __prci_data *pd = pc->pd; if (enable) { __prci_wrpll_write_cfg1(pd, pwd, PRCI_COREPLLCFG1_CKE_MASK); if (pwd->disable_bypass) pwd->disable_bypass(pd); if (pwd->release_reset) pwd->release_reset(pd); } else { 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); } return 0; } /* TLCLKSEL clock integration */ unsigned long sifive_prci_tlclksel_recalc_rate(struct __prci_clock *pc, unsigned long parent_rate) { 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 __prci_clock *pc, unsigned long parent_rate) { struct __prci_data *pd = pc->pd; u32 div = __prci_readl(pd, PRCI_HFPCLKPLLDIV_OFFSET); return div_u64(parent_rate, div + 2); } /** * 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 */ } static int __prci_consumer_reset(const char *rst_name, bool trigger) { struct udevice *dev; struct reset_ctl rst_sig; int ret; ret = uclass_get_device_by_driver(UCLASS_RESET, DM_DRIVER_GET(sifive_reset), &dev); if (ret) { dev_err(dev, "Reset driver not found: %d\n", ret); return ret; } ret = reset_get_by_name(dev, rst_name, &rst_sig); if (ret) { dev_err(dev, "failed to get %s reset\n", rst_name); return ret; } if (reset_valid(&rst_sig)) { if (trigger) ret = reset_deassert(&rst_sig); else ret = reset_assert(&rst_sig); if (ret) { dev_err(dev, "failed to trigger reset id = %ld\n", rst_sig.id); return ret; } } return ret; } /** * sifive_prci_ddr_release_reset() - Release DDR reset * @pd: struct __prci_data * for the PRCI containing the DDRCLK mux reg * */ void sifive_prci_ddr_release_reset(struct __prci_data *pd) { /* Release DDR ctrl reset */ __prci_consumer_reset("ddr_ctrl", true); /* HACK to get the '1 full controller clock cycle'. */ asm volatile ("fence"); /* Release DDR AXI reset */ __prci_consumer_reset("ddr_axi", true); /* Release DDR AHB reset */ __prci_consumer_reset("ddr_ahb", true); /* Release DDR PHY reset */ __prci_consumer_reset("ddr_phy", true); /* HACK to get the '1 full controller clock cycle'. */ asm volatile ("fence"); /* * These take like 16 cycles to actually propagate. We can't go sending * stuff before they come out of reset. So wait. */ for (int i = 0; i < 256; i++) asm volatile ("nop"); } /** * sifive_prci_ethernet_release_reset() - Release ethernet reset * @pd: struct __prci_data * for the PRCI containing the Ethernet CLK mux reg * */ void sifive_prci_ethernet_release_reset(struct __prci_data *pd) { /* Release GEMGXL reset */ __prci_consumer_reset("gemgxl_reset", true); /* Procmon => core clock */ __prci_writel(PRCI_PROCMONCFG_CORE_CLOCK_MASK, PRCI_PROCMONCFG_OFFSET, pd); /* Release Chiplink reset */ __prci_consumer_reset("cltx_reset", true); } /** * sifive_prci_cltx_release_reset() - Release cltx reset * @pd: struct __prci_data * for the PRCI containing the Ethernet CLK mux reg * */ void sifive_prci_cltx_release_reset(struct __prci_data *pd) { /* Release CLTX reset */ __prci_consumer_reset("cltx_reset", true); } /* 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 PLL 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 */ } static ulong sifive_prci_parent_rate(struct __prci_clock *pc, struct prci_clk_desc *data) { ulong parent_rate; ulong i; struct __prci_clock *p; if (strcmp(pc->parent_name, "corepll") == 0 || strcmp(pc->parent_name, "hfpclkpll") == 0) { for (i = 0; i < data->num_clks; i++) { if (strcmp(pc->parent_name, data->clks[i].name) == 0) break; } if (i >= data->num_clks) return -ENXIO; p = &data->clks[i]; if (!p->pd || !p->ops->recalc_rate) return -ENXIO; return p->ops->recalc_rate(p, sifive_prci_parent_rate(p, data)); } if (strcmp(pc->parent_name, "rtcclk") == 0) parent_rate = clk_get_rate(&pc->pd->parent_rtcclk); else parent_rate = clk_get_rate(&pc->pd->parent_hfclk); return parent_rate; } static ulong sifive_prci_get_rate(struct clk *clk) { struct __prci_clock *pc; struct prci_clk_desc *data = (struct prci_clk_desc *)dev_get_driver_data(clk->dev); if (data->num_clks <= clk->id) return -ENXIO; pc = &data->clks[clk->id]; if (!pc->pd || !pc->ops->recalc_rate) return -ENXIO; return pc->ops->recalc_rate(pc, sifive_prci_parent_rate(pc, data)); } static ulong sifive_prci_set_rate(struct clk *clk, ulong rate) { int err; struct __prci_clock *pc; struct prci_clk_desc *data = (struct prci_clk_desc *)dev_get_driver_data(clk->dev); if (data->num_clks <= clk->id) return -ENXIO; pc = &data->clks[clk->id]; if (!pc->pd || !pc->ops->set_rate) return -ENXIO; err = pc->ops->set_rate(pc, rate, sifive_prci_parent_rate(pc, data)); if (err) return err; return rate; } static int sifive_prci_enable(struct clk *clk) { struct __prci_clock *pc; int ret = 0; struct prci_clk_desc *data = (struct prci_clk_desc *)dev_get_driver_data(clk->dev); if (data->num_clks <= clk->id) return -ENXIO; pc = &data->clks[clk->id]; if (!pc->pd) return -ENXIO; if (pc->ops->enable_clk) ret = pc->ops->enable_clk(pc, 1); return ret; } static int sifive_prci_disable(struct clk *clk) { struct __prci_clock *pc; int ret = 0; struct prci_clk_desc *data = (struct prci_clk_desc *)dev_get_driver_data(clk->dev); if (data->num_clks <= clk->id) return -ENXIO; pc = &data->clks[clk->id]; if (!pc->pd) return -ENXIO; if (pc->ops->enable_clk) ret = pc->ops->enable_clk(pc, 0); return ret; } static int sifive_prci_probe(struct udevice *dev) { int i, err; struct __prci_clock *pc; struct __prci_data *pd = dev_get_priv(dev); struct prci_clk_desc *data = (struct prci_clk_desc *)dev_get_driver_data(dev); pd->va = (void *)dev_read_addr(dev); if (IS_ERR(pd->va)) return PTR_ERR(pd->va); err = clk_get_by_index(dev, 0, &pd->parent_hfclk); if (err) return err; err = clk_get_by_index(dev, 1, &pd->parent_rtcclk); if (err) return err; for (i = 0; i < data->num_clks; ++i) { pc = &data->clks[i]; pc->pd = pd; if (pc->pwd) __prci_wrpll_read_cfg0(pd, pc->pwd); } if (IS_ENABLED(CONFIG_SPL_BUILD)) { if (device_is_compatible(dev, "sifive,fu740-c000-prci")) { u32 prci_pll_reg; unsigned long parent_rate; prci_pll_reg = readl(pd->va + PRCI_PRCIPLL_OFFSET); if (prci_pll_reg & PRCI_PRCIPLL_HFPCLKPLL) { /* * Only initialize the HFPCLK PLL. In this * case the design uses hfpclk to drive * Chiplink */ pc = &data->clks[PRCI_CLK_HFPCLKPLL]; parent_rate = sifive_prci_parent_rate(pc, data); sifive_prci_wrpll_set_rate(pc, 260000000, parent_rate); pc->ops->enable_clk(pc, 1); } else if (prci_pll_reg & PRCI_PRCIPLL_CLTXPLL) { /* CLTX pll init */ pc = &data->clks[PRCI_CLK_CLTXPLL]; parent_rate = sifive_prci_parent_rate(pc, data); sifive_prci_wrpll_set_rate(pc, 260000000, parent_rate); pc->ops->enable_clk(pc, 1); } } } return 0; } static struct clk_ops sifive_prci_ops = { .set_rate = sifive_prci_set_rate, .get_rate = sifive_prci_get_rate, .enable = sifive_prci_enable, .disable = sifive_prci_disable, }; static int sifive_clk_bind(struct udevice *dev) { return sifive_reset_bind(dev, PRCI_DEVICERESETCNT); } static const struct udevice_id sifive_prci_ids[] = { { .compatible = "sifive,fu540-c000-prci", .data = (ulong)&prci_clk_fu540 }, { .compatible = "sifive,fu740-c000-prci", .data = (ulong)&prci_clk_fu740 }, { } }; U_BOOT_DRIVER(sifive_prci) = { .name = "sifive-prci", .id = UCLASS_CLK, .of_match = sifive_prci_ids, .probe = sifive_prci_probe, .ops = &sifive_prci_ops, .priv_auto = sizeof(struct __prci_data), .bind = sifive_clk_bind, };