// SPDX-License-Identifier: GPL-2.0-or-later /* * arch/arm/mach-ep93xx/clock.c * Clock control for Cirrus EP93xx chips. * * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org> */ #define pr_fmt(fmt) "ep93xx " KBUILD_MODNAME ": " fmt #include <linux/kernel.h> #include <linux/clk.h> #include <linux/err.h> #include <linux/module.h> #include <linux/string.h> #include <linux/io.h> #include <linux/spinlock.h> #include <linux/clkdev.h> #include <linux/clk-provider.h> #include <linux/soc/cirrus/ep93xx.h> #include "hardware.h" #include <asm/div64.h> #include "soc.h" static DEFINE_SPINLOCK(clk_lock); static char fclk_divisors[] = { 1, 2, 4, 8, 16, 1, 1, 1 }; static char hclk_divisors[] = { 1, 2, 4, 5, 6, 8, 16, 32 }; static char pclk_divisors[] = { 1, 2, 4, 8 }; static char adc_divisors[] = { 16, 4 }; static char sclk_divisors[] = { 2, 4 }; static char lrclk_divisors[] = { 32, 64, 128 }; static const char * const mux_parents[] = { "xtali", "pll1", "pll2" }; /* * PLL rate = 14.7456 MHz * (X1FBD + 1) * (X2FBD + 1) / (X2IPD + 1) / 2^PS */ static unsigned long calc_pll_rate(unsigned long long rate, u32 config_word) { int i; rate *= ((config_word >> 11) & 0x1f) + 1; /* X1FBD */ rate *= ((config_word >> 5) & 0x3f) + 1; /* X2FBD */ do_div(rate, (config_word & 0x1f) + 1); /* X2IPD */ for (i = 0; i < ((config_word >> 16) & 3); i++) /* PS */ rate >>= 1; return (unsigned long)rate; } struct clk_psc { struct clk_hw hw; void __iomem *reg; u8 bit_idx; u32 mask; u8 shift; u8 width; char *div; u8 num_div; spinlock_t *lock; }; #define to_clk_psc(_hw) container_of(_hw, struct clk_psc, hw) static int ep93xx_clk_is_enabled(struct clk_hw *hw) { struct clk_psc *psc = to_clk_psc(hw); u32 val = readl(psc->reg); return (val & BIT(psc->bit_idx)) ? 1 : 0; } static int ep93xx_clk_enable(struct clk_hw *hw) { struct clk_psc *psc = to_clk_psc(hw); unsigned long flags = 0; u32 val; if (psc->lock) spin_lock_irqsave(psc->lock, flags); val = __raw_readl(psc->reg); val |= BIT(psc->bit_idx); ep93xx_syscon_swlocked_write(val, psc->reg); if (psc->lock) spin_unlock_irqrestore(psc->lock, flags); return 0; } static void ep93xx_clk_disable(struct clk_hw *hw) { struct clk_psc *psc = to_clk_psc(hw); unsigned long flags = 0; u32 val; if (psc->lock) spin_lock_irqsave(psc->lock, flags); val = __raw_readl(psc->reg); val &= ~BIT(psc->bit_idx); ep93xx_syscon_swlocked_write(val, psc->reg); if (psc->lock) spin_unlock_irqrestore(psc->lock, flags); } static const struct clk_ops clk_ep93xx_gate_ops = { .enable = ep93xx_clk_enable, .disable = ep93xx_clk_disable, .is_enabled = ep93xx_clk_is_enabled, }; static struct clk_hw *ep93xx_clk_register_gate(const char *name, const char *parent_name, void __iomem *reg, u8 bit_idx) { struct clk_init_data init; struct clk_psc *psc; struct clk *clk; psc = kzalloc(sizeof(*psc), GFP_KERNEL); if (!psc) return ERR_PTR(-ENOMEM); init.name = name; init.ops = &clk_ep93xx_gate_ops; init.flags = CLK_SET_RATE_PARENT; init.parent_names = (parent_name ? &parent_name : NULL); init.num_parents = (parent_name ? 1 : 0); psc->reg = reg; psc->bit_idx = bit_idx; psc->hw.init = &init; psc->lock = &clk_lock; clk = clk_register(NULL, &psc->hw); if (IS_ERR(clk)) { kfree(psc); return ERR_CAST(clk); } return &psc->hw; } static u8 ep93xx_mux_get_parent(struct clk_hw *hw) { struct clk_psc *psc = to_clk_psc(hw); u32 val = __raw_readl(psc->reg); if (!(val & EP93XX_SYSCON_CLKDIV_ESEL)) return 0; if (!(val & EP93XX_SYSCON_CLKDIV_PSEL)) return 1; return 2; } static int ep93xx_mux_set_parent_lock(struct clk_hw *hw, u8 index) { struct clk_psc *psc = to_clk_psc(hw); unsigned long flags = 0; u32 val; if (index >= ARRAY_SIZE(mux_parents)) return -EINVAL; if (psc->lock) spin_lock_irqsave(psc->lock, flags); val = __raw_readl(psc->reg); val &= ~(EP93XX_SYSCON_CLKDIV_ESEL | EP93XX_SYSCON_CLKDIV_PSEL); if (index != 0) { val |= EP93XX_SYSCON_CLKDIV_ESEL; val |= (index - 1) ? EP93XX_SYSCON_CLKDIV_PSEL : 0; } ep93xx_syscon_swlocked_write(val, psc->reg); if (psc->lock) spin_unlock_irqrestore(psc->lock, flags); return 0; } static bool is_best(unsigned long rate, unsigned long now, unsigned long best) { return abs(rate - now) < abs(rate - best); } static int ep93xx_mux_determine_rate(struct clk_hw *hw, struct clk_rate_request *req) { unsigned long rate = req->rate; struct clk *best_parent = NULL; unsigned long __parent_rate; unsigned long best_rate = 0, actual_rate, mclk_rate; unsigned long best_parent_rate; int __div = 0, __pdiv = 0; int i; /* * Try the two pll's and the external clock * Because the valid predividers are 2, 2.5 and 3, we multiply * all the clocks by 2 to avoid floating point math. * * This is based on the algorithm in the ep93xx raster guide: * http://be-a-maverick.com/en/pubs/appNote/AN269REV1.pdf * */ for (i = 0; i < ARRAY_SIZE(mux_parents); i++) { struct clk *parent = clk_get_sys(mux_parents[i], NULL); __parent_rate = clk_get_rate(parent); mclk_rate = __parent_rate * 2; /* Try each predivider value */ for (__pdiv = 4; __pdiv <= 6; __pdiv++) { __div = mclk_rate / (rate * __pdiv); if (__div < 2 || __div > 127) continue; actual_rate = mclk_rate / (__pdiv * __div); if (is_best(rate, actual_rate, best_rate)) { best_rate = actual_rate; best_parent_rate = __parent_rate; best_parent = parent; } } } if (!best_parent) return -EINVAL; req->best_parent_rate = best_parent_rate; req->best_parent_hw = __clk_get_hw(best_parent); req->rate = best_rate; return 0; } static unsigned long ep93xx_ddiv_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { struct clk_psc *psc = to_clk_psc(hw); unsigned long rate = 0; u32 val = __raw_readl(psc->reg); int __pdiv = ((val >> EP93XX_SYSCON_CLKDIV_PDIV_SHIFT) & 0x03); int __div = val & 0x7f; if (__div > 0) rate = (parent_rate * 2) / ((__pdiv + 3) * __div); return rate; } static int ep93xx_ddiv_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate) { struct clk_psc *psc = to_clk_psc(hw); int pdiv = 0, div = 0; unsigned long best_rate = 0, actual_rate, mclk_rate; int __div = 0, __pdiv = 0; u32 val; mclk_rate = parent_rate * 2; for (__pdiv = 4; __pdiv <= 6; __pdiv++) { __div = mclk_rate / (rate * __pdiv); if (__div < 2 || __div > 127) continue; actual_rate = mclk_rate / (__pdiv * __div); if (is_best(rate, actual_rate, best_rate)) { pdiv = __pdiv - 3; div = __div; best_rate = actual_rate; } } if (!best_rate) return -EINVAL; val = __raw_readl(psc->reg); /* Clear old dividers */ val &= ~0x37f; /* Set the new pdiv and div bits for the new clock rate */ val |= (pdiv << EP93XX_SYSCON_CLKDIV_PDIV_SHIFT) | div; ep93xx_syscon_swlocked_write(val, psc->reg); return 0; } static const struct clk_ops clk_ddiv_ops = { .enable = ep93xx_clk_enable, .disable = ep93xx_clk_disable, .is_enabled = ep93xx_clk_is_enabled, .get_parent = ep93xx_mux_get_parent, .set_parent = ep93xx_mux_set_parent_lock, .determine_rate = ep93xx_mux_determine_rate, .recalc_rate = ep93xx_ddiv_recalc_rate, .set_rate = ep93xx_ddiv_set_rate, }; static struct clk_hw *clk_hw_register_ddiv(const char *name, void __iomem *reg, u8 bit_idx) { struct clk_init_data init; struct clk_psc *psc; struct clk *clk; psc = kzalloc(sizeof(*psc), GFP_KERNEL); if (!psc) return ERR_PTR(-ENOMEM); init.name = name; init.ops = &clk_ddiv_ops; init.flags = 0; init.parent_names = mux_parents; init.num_parents = ARRAY_SIZE(mux_parents); psc->reg = reg; psc->bit_idx = bit_idx; psc->lock = &clk_lock; psc->hw.init = &init; clk = clk_register(NULL, &psc->hw); if (IS_ERR(clk)) { kfree(psc); return ERR_CAST(clk); } return &psc->hw; } static unsigned long ep93xx_div_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { struct clk_psc *psc = to_clk_psc(hw); u32 val = __raw_readl(psc->reg); u8 index = (val & psc->mask) >> psc->shift; if (index > psc->num_div) return 0; return DIV_ROUND_UP_ULL(parent_rate, psc->div[index]); } static long ep93xx_div_round_rate(struct clk_hw *hw, unsigned long rate, unsigned long *parent_rate) { struct clk_psc *psc = to_clk_psc(hw); unsigned long best = 0, now, maxdiv; int i; maxdiv = psc->div[psc->num_div - 1]; for (i = 0; i < psc->num_div; i++) { if ((rate * psc->div[i]) == *parent_rate) return DIV_ROUND_UP_ULL((u64)*parent_rate, psc->div[i]); now = DIV_ROUND_UP_ULL((u64)*parent_rate, psc->div[i]); if (is_best(rate, now, best)) best = now; } if (!best) best = DIV_ROUND_UP_ULL(*parent_rate, maxdiv); return best; } static int ep93xx_div_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate) { struct clk_psc *psc = to_clk_psc(hw); u32 val = __raw_readl(psc->reg) & ~psc->mask; int i; for (i = 0; i < psc->num_div; i++) if (rate == parent_rate / psc->div[i]) { val |= i << psc->shift; break; } if (i == psc->num_div) return -EINVAL; ep93xx_syscon_swlocked_write(val, psc->reg); return 0; } static const struct clk_ops ep93xx_div_ops = { .enable = ep93xx_clk_enable, .disable = ep93xx_clk_disable, .is_enabled = ep93xx_clk_is_enabled, .recalc_rate = ep93xx_div_recalc_rate, .round_rate = ep93xx_div_round_rate, .set_rate = ep93xx_div_set_rate, }; static struct clk_hw *clk_hw_register_div(const char *name, const char *parent_name, void __iomem *reg, u8 enable_bit, u8 shift, u8 width, char *clk_divisors, u8 num_div) { struct clk_init_data init; struct clk_psc *psc; struct clk *clk; psc = kzalloc(sizeof(*psc), GFP_KERNEL); if (!psc) return ERR_PTR(-ENOMEM); init.name = name; init.ops = &ep93xx_div_ops; init.flags = 0; init.parent_names = (parent_name ? &parent_name : NULL); init.num_parents = 1; psc->reg = reg; psc->bit_idx = enable_bit; psc->mask = GENMASK(shift + width - 1, shift); psc->shift = shift; psc->div = clk_divisors; psc->num_div = num_div; psc->lock = &clk_lock; psc->hw.init = &init; clk = clk_register(NULL, &psc->hw); if (IS_ERR(clk)) { kfree(psc); return ERR_CAST(clk); } return &psc->hw; } struct ep93xx_gate { unsigned int bit; const char *dev_id; const char *con_id; }; static struct ep93xx_gate ep93xx_uarts[] = { {EP93XX_SYSCON_DEVCFG_U1EN, "apb:uart1", NULL}, {EP93XX_SYSCON_DEVCFG_U2EN, "apb:uart2", NULL}, {EP93XX_SYSCON_DEVCFG_U3EN, "apb:uart3", NULL}, }; static void __init ep93xx_uart_clock_init(void) { unsigned int i; struct clk_hw *hw; u32 value; unsigned int clk_uart_div; value = __raw_readl(EP93XX_SYSCON_PWRCNT); if (value & EP93XX_SYSCON_PWRCNT_UARTBAUD) clk_uart_div = 1; else clk_uart_div = 2; hw = clk_hw_register_fixed_factor(NULL, "uart", "xtali", 0, 1, clk_uart_div); /* parenting uart gate clocks to uart clock */ for (i = 0; i < ARRAY_SIZE(ep93xx_uarts); i++) { hw = ep93xx_clk_register_gate(ep93xx_uarts[i].dev_id, "uart", EP93XX_SYSCON_DEVCFG, ep93xx_uarts[i].bit); clk_hw_register_clkdev(hw, NULL, ep93xx_uarts[i].dev_id); } } static struct ep93xx_gate ep93xx_dmas[] = { {EP93XX_SYSCON_PWRCNT_DMA_M2P0, NULL, "m2p0"}, {EP93XX_SYSCON_PWRCNT_DMA_M2P1, NULL, "m2p1"}, {EP93XX_SYSCON_PWRCNT_DMA_M2P2, NULL, "m2p2"}, {EP93XX_SYSCON_PWRCNT_DMA_M2P3, NULL, "m2p3"}, {EP93XX_SYSCON_PWRCNT_DMA_M2P4, NULL, "m2p4"}, {EP93XX_SYSCON_PWRCNT_DMA_M2P5, NULL, "m2p5"}, {EP93XX_SYSCON_PWRCNT_DMA_M2P6, NULL, "m2p6"}, {EP93XX_SYSCON_PWRCNT_DMA_M2P7, NULL, "m2p7"}, {EP93XX_SYSCON_PWRCNT_DMA_M2P8, NULL, "m2p8"}, {EP93XX_SYSCON_PWRCNT_DMA_M2P9, NULL, "m2p9"}, {EP93XX_SYSCON_PWRCNT_DMA_M2M0, NULL, "m2m0"}, {EP93XX_SYSCON_PWRCNT_DMA_M2M1, NULL, "m2m1"}, }; static void __init ep93xx_dma_clock_init(void) { unsigned int i; struct clk_hw *hw; int ret; for (i = 0; i < ARRAY_SIZE(ep93xx_dmas); i++) { hw = clk_hw_register_gate(NULL, ep93xx_dmas[i].con_id, "hclk", 0, EP93XX_SYSCON_PWRCNT, ep93xx_dmas[i].bit, 0, &clk_lock); ret = clk_hw_register_clkdev(hw, ep93xx_dmas[i].con_id, NULL); if (ret) pr_err("%s: failed to register lookup %s\n", __func__, ep93xx_dmas[i].con_id); } } static int __init ep93xx_clock_init(void) { u32 value; struct clk_hw *hw; unsigned long clk_pll1_rate; unsigned long clk_f_rate; unsigned long clk_h_rate; unsigned long clk_p_rate; unsigned long clk_pll2_rate; unsigned int clk_f_div; unsigned int clk_h_div; unsigned int clk_p_div; unsigned int clk_usb_div; unsigned long clk_spi_div; hw = clk_hw_register_fixed_rate(NULL, "xtali", NULL, 0, EP93XX_EXT_CLK_RATE); clk_hw_register_clkdev(hw, NULL, "xtali"); /* Determine the bootloader configured pll1 rate */ value = __raw_readl(EP93XX_SYSCON_CLKSET1); if (!(value & EP93XX_SYSCON_CLKSET1_NBYP1)) clk_pll1_rate = EP93XX_EXT_CLK_RATE; else clk_pll1_rate = calc_pll_rate(EP93XX_EXT_CLK_RATE, value); hw = clk_hw_register_fixed_rate(NULL, "pll1", "xtali", 0, clk_pll1_rate); clk_hw_register_clkdev(hw, NULL, "pll1"); /* Initialize the pll1 derived clocks */ clk_f_div = fclk_divisors[(value >> 25) & 0x7]; clk_h_div = hclk_divisors[(value >> 20) & 0x7]; clk_p_div = pclk_divisors[(value >> 18) & 0x3]; hw = clk_hw_register_fixed_factor(NULL, "fclk", "pll1", 0, 1, clk_f_div); clk_f_rate = clk_get_rate(hw->clk); hw = clk_hw_register_fixed_factor(NULL, "hclk", "pll1", 0, 1, clk_h_div); clk_h_rate = clk_get_rate(hw->clk); hw = clk_hw_register_fixed_factor(NULL, "pclk", "hclk", 0, 1, clk_p_div); clk_p_rate = clk_get_rate(hw->clk); clk_hw_register_clkdev(hw, "apb_pclk", NULL); ep93xx_dma_clock_init(); /* Determine the bootloader configured pll2 rate */ value = __raw_readl(EP93XX_SYSCON_CLKSET2); if (!(value & EP93XX_SYSCON_CLKSET2_NBYP2)) clk_pll2_rate = EP93XX_EXT_CLK_RATE; else if (value & EP93XX_SYSCON_CLKSET2_PLL2_EN) clk_pll2_rate = calc_pll_rate(EP93XX_EXT_CLK_RATE, value); else clk_pll2_rate = 0; hw = clk_hw_register_fixed_rate(NULL, "pll2", "xtali", 0, clk_pll2_rate); clk_hw_register_clkdev(hw, NULL, "pll2"); /* Initialize the pll2 derived clocks */ /* * These four bits set the divide ratio between the PLL2 * output and the USB clock. * 0000 - Divide by 1 * 0001 - Divide by 2 * 0010 - Divide by 3 * 0011 - Divide by 4 * 0100 - Divide by 5 * 0101 - Divide by 6 * 0110 - Divide by 7 * 0111 - Divide by 8 * 1000 - Divide by 9 * 1001 - Divide by 10 * 1010 - Divide by 11 * 1011 - Divide by 12 * 1100 - Divide by 13 * 1101 - Divide by 14 * 1110 - Divide by 15 * 1111 - Divide by 1 * On power-on-reset these bits are reset to 0000b. */ clk_usb_div = (((value >> 28) & 0xf) + 1); hw = clk_hw_register_fixed_factor(NULL, "usb_clk", "pll2", 0, 1, clk_usb_div); hw = clk_hw_register_gate(NULL, "ohci-platform", "usb_clk", 0, EP93XX_SYSCON_PWRCNT, EP93XX_SYSCON_PWRCNT_USH_EN, 0, &clk_lock); clk_hw_register_clkdev(hw, NULL, "ohci-platform"); /* * EP93xx SSP clock rate was doubled in version E2. For more information * see: * http://www.cirrus.com/en/pubs/appNote/AN273REV4.pdf */ clk_spi_div = 1; if (ep93xx_chip_revision() < EP93XX_CHIP_REV_E2) clk_spi_div = 2; hw = clk_hw_register_fixed_factor(NULL, "ep93xx-spi.0", "xtali", 0, 1, clk_spi_div); clk_hw_register_clkdev(hw, NULL, "ep93xx-spi.0"); /* pwm clock */ hw = clk_hw_register_fixed_factor(NULL, "pwm_clk", "xtali", 0, 1, 1); clk_hw_register_clkdev(hw, "pwm_clk", NULL); pr_info("PLL1 running at %ld MHz, PLL2 at %ld MHz\n", clk_pll1_rate / 1000000, clk_pll2_rate / 1000000); pr_info("FCLK %ld MHz, HCLK %ld MHz, PCLK %ld MHz\n", clk_f_rate / 1000000, clk_h_rate / 1000000, clk_p_rate / 1000000); ep93xx_uart_clock_init(); /* touchscreen/adc clock */ hw = clk_hw_register_div("ep93xx-adc", "xtali", EP93XX_SYSCON_KEYTCHCLKDIV, EP93XX_SYSCON_KEYTCHCLKDIV_TSEN, EP93XX_SYSCON_KEYTCHCLKDIV_ADIV, 1, adc_divisors, ARRAY_SIZE(adc_divisors)); clk_hw_register_clkdev(hw, NULL, "ep93xx-adc"); /* keypad clock */ hw = clk_hw_register_div("ep93xx-keypad", "xtali", EP93XX_SYSCON_KEYTCHCLKDIV, EP93XX_SYSCON_KEYTCHCLKDIV_KEN, EP93XX_SYSCON_KEYTCHCLKDIV_KDIV, 1, adc_divisors, ARRAY_SIZE(adc_divisors)); clk_hw_register_clkdev(hw, NULL, "ep93xx-keypad"); /* On reset PDIV and VDIV is set to zero, while PDIV zero * means clock disable, VDIV shouldn't be zero. * So i set both dividers to minimum. */ /* ENA - Enable CLK divider. */ /* PDIV - 00 - Disable clock */ /* VDIV - at least 2 */ /* Check and enable video clk registers */ value = __raw_readl(EP93XX_SYSCON_VIDCLKDIV); value |= (1 << EP93XX_SYSCON_CLKDIV_PDIV_SHIFT) | 2; ep93xx_syscon_swlocked_write(value, EP93XX_SYSCON_VIDCLKDIV); /* check and enable i2s clk registers */ value = __raw_readl(EP93XX_SYSCON_I2SCLKDIV); value |= (1 << EP93XX_SYSCON_CLKDIV_PDIV_SHIFT) | 2; ep93xx_syscon_swlocked_write(value, EP93XX_SYSCON_I2SCLKDIV); /* video clk */ hw = clk_hw_register_ddiv("ep93xx-fb", EP93XX_SYSCON_VIDCLKDIV, EP93XX_SYSCON_CLKDIV_ENABLE); clk_hw_register_clkdev(hw, NULL, "ep93xx-fb"); /* i2s clk */ hw = clk_hw_register_ddiv("mclk", EP93XX_SYSCON_I2SCLKDIV, EP93XX_SYSCON_CLKDIV_ENABLE); clk_hw_register_clkdev(hw, "mclk", "ep93xx-i2s"); /* i2s sclk */ #define EP93XX_I2SCLKDIV_SDIV_SHIFT 16 #define EP93XX_I2SCLKDIV_SDIV_WIDTH 1 hw = clk_hw_register_div("sclk", "mclk", EP93XX_SYSCON_I2SCLKDIV, EP93XX_SYSCON_I2SCLKDIV_SENA, EP93XX_I2SCLKDIV_SDIV_SHIFT, EP93XX_I2SCLKDIV_SDIV_WIDTH, sclk_divisors, ARRAY_SIZE(sclk_divisors)); clk_hw_register_clkdev(hw, "sclk", "ep93xx-i2s"); /* i2s lrclk */ #define EP93XX_I2SCLKDIV_LRDIV32_SHIFT 17 #define EP93XX_I2SCLKDIV_LRDIV32_WIDTH 3 hw = clk_hw_register_div("lrclk", "sclk", EP93XX_SYSCON_I2SCLKDIV, EP93XX_SYSCON_I2SCLKDIV_SENA, EP93XX_I2SCLKDIV_LRDIV32_SHIFT, EP93XX_I2SCLKDIV_LRDIV32_WIDTH, lrclk_divisors, ARRAY_SIZE(lrclk_divisors)); clk_hw_register_clkdev(hw, "lrclk", "ep93xx-i2s"); return 0; } postcore_initcall(ep93xx_clock_init);