/* linux/arch/arm/mach-s3c2443/clock.c * * Copyright (c) 2007, 2010 Simtec Electronics * Ben Dooks * * S3C2443 Clock control support * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * 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. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* We currently have to assume that the system is running * from the XTPll input, and that all ***REFCLKs are being * fed from it, as we cannot read the state of OM[4] from * software. * * It would be possible for each board initialisation to * set the correct muxing at initialisation */ static int s3c2443_gate(void __iomem *reg, struct clk *clk, int enable) { u32 ctrlbit = clk->ctrlbit; u32 con = __raw_readl(reg); if (enable) con |= ctrlbit; else con &= ~ctrlbit; __raw_writel(con, reg); return 0; } static int s3c2443_clkcon_enable_h(struct clk *clk, int enable) { return s3c2443_gate(S3C2443_HCLKCON, clk, enable); } static int s3c2443_clkcon_enable_p(struct clk *clk, int enable) { return s3c2443_gate(S3C2443_PCLKCON, clk, enable); } static int s3c2443_clkcon_enable_s(struct clk *clk, int enable) { return s3c2443_gate(S3C2443_SCLKCON, clk, enable); } /* clock selections */ /* mpllref is a direct descendant of clk_xtal by default, but it is not * elided as the EPLL can be either sourced by the XTAL or EXTCLK and as * such directly equating the two source clocks is impossible. */ static struct clk clk_mpllref = { .name = "mpllref", .parent = &clk_xtal, .id = -1, }; static struct clk clk_i2s_ext = { .name = "i2s-ext", .id = -1, }; static struct clk *clk_epllref_sources[] = { [0] = &clk_mpllref, [1] = &clk_mpllref, [2] = &clk_xtal, [3] = &clk_ext, }; static struct clksrc_clk clk_epllref = { .clk = { .name = "epllref", .id = -1, }, .sources = &(struct clksrc_sources) { .sources = clk_epllref_sources, .nr_sources = ARRAY_SIZE(clk_epllref_sources), }, .reg_src = { .reg = S3C2443_CLKSRC, .size = 2, .shift = 7 }, }; static unsigned long s3c2443_getrate_mdivclk(struct clk *clk) { unsigned long parent_rate = clk_get_rate(clk->parent); unsigned long div = __raw_readl(S3C2443_CLKDIV0); div &= S3C2443_CLKDIV0_EXTDIV_MASK; div >>= (S3C2443_CLKDIV0_EXTDIV_SHIFT-1); /* x2 */ return parent_rate / (div + 1); } static struct clk clk_mdivclk = { .name = "mdivclk", .parent = &clk_mpllref, .id = -1, .ops = &(struct clk_ops) { .get_rate = s3c2443_getrate_mdivclk, }, }; static struct clk *clk_msysclk_sources[] = { [0] = &clk_mpllref, [1] = &clk_mpll, [2] = &clk_mdivclk, [3] = &clk_mpllref, }; static struct clksrc_clk clk_msysclk = { .clk = { .name = "msysclk", .parent = &clk_xtal, .id = -1, }, .sources = &(struct clksrc_sources) { .sources = clk_msysclk_sources, .nr_sources = ARRAY_SIZE(clk_msysclk_sources), }, .reg_src = { .reg = S3C2443_CLKSRC, .size = 2, .shift = 3 }, }; /* armdiv * * this clock is sourced from msysclk and can have a number of * divider values applied to it to then be fed into armclk. */ /* armdiv divisor table */ static unsigned int armdiv[16] = { [S3C2443_CLKDIV0_ARMDIV_1 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 1, [S3C2443_CLKDIV0_ARMDIV_2 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 2, [S3C2443_CLKDIV0_ARMDIV_3 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 3, [S3C2443_CLKDIV0_ARMDIV_4 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 4, [S3C2443_CLKDIV0_ARMDIV_6 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 6, [S3C2443_CLKDIV0_ARMDIV_8 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 8, [S3C2443_CLKDIV0_ARMDIV_12 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 12, [S3C2443_CLKDIV0_ARMDIV_16 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 16, }; static inline unsigned int s3c2443_fclk_div(unsigned long clkcon0) { clkcon0 &= S3C2443_CLKDIV0_ARMDIV_MASK; return armdiv[clkcon0 >> S3C2443_CLKDIV0_ARMDIV_SHIFT]; } static unsigned long s3c2443_armclk_roundrate(struct clk *clk, unsigned long rate) { unsigned long parent = clk_get_rate(clk->parent); unsigned long calc; unsigned best = 256; /* bigger than any value */ unsigned div; int ptr; for (ptr = 0; ptr < ARRAY_SIZE(armdiv); ptr++) { div = armdiv[ptr]; calc = parent / div; if (calc <= rate && div < best) best = div; } return parent / best; } static int s3c2443_armclk_setrate(struct clk *clk, unsigned long rate) { unsigned long parent = clk_get_rate(clk->parent); unsigned long calc; unsigned div; unsigned best = 256; /* bigger than any value */ int ptr; int val = -1; for (ptr = 0; ptr < ARRAY_SIZE(armdiv); ptr++) { div = armdiv[ptr]; calc = parent / div; if (calc <= rate && div < best) { best = div; val = ptr; } } if (val >= 0) { unsigned long clkcon0; clkcon0 = __raw_readl(S3C2443_CLKDIV0); clkcon0 &= S3C2443_CLKDIV0_ARMDIV_MASK; clkcon0 |= val << S3C2443_CLKDIV0_ARMDIV_SHIFT; __raw_writel(clkcon0, S3C2443_CLKDIV0); } return (val == -1) ? -EINVAL : 0; } static struct clk clk_armdiv = { .name = "armdiv", .id = -1, .parent = &clk_msysclk.clk, .ops = &(struct clk_ops) { .round_rate = s3c2443_armclk_roundrate, .set_rate = s3c2443_armclk_setrate, }, }; /* armclk * * this is the clock fed into the ARM core itself, from armdiv or from hclk. */ static struct clk *clk_arm_sources[] = { [0] = &clk_armdiv, [1] = &clk_h, }; static struct clksrc_clk clk_arm = { .clk = { .name = "armclk", .id = -1, }, .sources = &(struct clksrc_sources) { .sources = clk_arm_sources, .nr_sources = ARRAY_SIZE(clk_arm_sources), }, .reg_src = { .reg = S3C2443_CLKDIV0, .size = 1, .shift = 13 }, }; /* esysclk * * this is sourced from either the EPLL or the EPLLref clock */ static struct clk *clk_sysclk_sources[] = { [0] = &clk_epllref.clk, [1] = &clk_epll, }; static struct clksrc_clk clk_esysclk = { .clk = { .name = "esysclk", .parent = &clk_epll, .id = -1, }, .sources = &(struct clksrc_sources) { .sources = clk_sysclk_sources, .nr_sources = ARRAY_SIZE(clk_sysclk_sources), }, .reg_src = { .reg = S3C2443_CLKSRC, .size = 1, .shift = 6 }, }; /* uartclk * * UART baud-rate clock sourced from esysclk via a divisor */ static struct clksrc_clk clk_uart = { .clk = { .name = "uartclk", .id = -1, .parent = &clk_esysclk.clk, }, .reg_div = { .reg = S3C2443_CLKDIV1, .size = 4, .shift = 8 }, }; /* hsspi * * high-speed spi clock, sourced from esysclk */ static struct clksrc_clk clk_hsspi = { .clk = { .name = "hsspi", .id = -1, .parent = &clk_esysclk.clk, .ctrlbit = S3C2443_SCLKCON_HSSPICLK, .enable = s3c2443_clkcon_enable_s, }, .reg_div = { .reg = S3C2443_CLKDIV1, .size = 2, .shift = 4 }, }; /* usbhost * * usb host bus-clock, usually 48MHz to provide USB bus clock timing */ static struct clksrc_clk clk_usb_bus_host = { .clk = { .name = "usb-bus-host-parent", .id = -1, .parent = &clk_esysclk.clk, .ctrlbit = S3C2443_SCLKCON_USBHOST, .enable = s3c2443_clkcon_enable_s, }, .reg_div = { .reg = S3C2443_CLKDIV1, .size = 2, .shift = 4 }, }; /* clk_hsmcc_div * * this clock is sourced from epll, and is fed through a divider, * to a mux controlled by sclkcon where either it or a extclk can * be fed to the hsmmc block */ static struct clksrc_clk clk_hsmmc_div = { .clk = { .name = "hsmmc-div", .id = -1, .parent = &clk_esysclk.clk, }, .reg_div = { .reg = S3C2443_CLKDIV1, .size = 2, .shift = 6 }, }; static int s3c2443_setparent_hsmmc(struct clk *clk, struct clk *parent) { unsigned long clksrc = __raw_readl(S3C2443_SCLKCON); clksrc &= ~(S3C2443_SCLKCON_HSMMCCLK_EXT | S3C2443_SCLKCON_HSMMCCLK_EPLL); if (parent == &clk_epll) clksrc |= S3C2443_SCLKCON_HSMMCCLK_EPLL; else if (parent == &clk_ext) clksrc |= S3C2443_SCLKCON_HSMMCCLK_EXT; else return -EINVAL; if (clk->usage > 0) { __raw_writel(clksrc, S3C2443_SCLKCON); } clk->parent = parent; return 0; } static int s3c2443_enable_hsmmc(struct clk *clk, int enable) { return s3c2443_setparent_hsmmc(clk, clk->parent); } static struct clk clk_hsmmc = { .name = "hsmmc-if", .id = -1, .parent = &clk_hsmmc_div.clk, .enable = s3c2443_enable_hsmmc, .ops = &(struct clk_ops) { .set_parent = s3c2443_setparent_hsmmc, }, }; /* i2s_eplldiv * * This clock is the output from the I2S divisor of ESYSCLK, and is seperate * from the mux that comes after it (cannot merge into one single clock) */ static struct clksrc_clk clk_i2s_eplldiv = { .clk = { .name = "i2s-eplldiv", .id = -1, .parent = &clk_esysclk.clk, }, .reg_div = { .reg = S3C2443_CLKDIV1, .size = 4, .shift = 12, }, }; /* i2s-ref * * i2s bus reference clock, selectable from external, esysclk or epllref * * Note, this used to be two clocks, but was compressed into one. */ struct clk *clk_i2s_srclist[] = { [0] = &clk_i2s_eplldiv.clk, [1] = &clk_i2s_ext, [2] = &clk_epllref.clk, [3] = &clk_epllref.clk, }; static struct clksrc_clk clk_i2s = { .clk = { .name = "i2s-if", .id = -1, .ctrlbit = S3C2443_SCLKCON_I2SCLK, .enable = s3c2443_clkcon_enable_s, }, .sources = &(struct clksrc_sources) { .sources = clk_i2s_srclist, .nr_sources = ARRAY_SIZE(clk_i2s_srclist), }, .reg_src = { .reg = S3C2443_CLKSRC, .size = 2, .shift = 14 }, }; /* cam-if * * camera interface bus-clock, divided down from esysclk */ static struct clksrc_clk clk_cam = { .clk = { .name = "camif-upll", /* same as 2440 name */ .id = -1, .parent = &clk_esysclk.clk, .ctrlbit = S3C2443_SCLKCON_CAMCLK, .enable = s3c2443_clkcon_enable_s, }, .reg_div = { .reg = S3C2443_CLKDIV1, .size = 4, .shift = 26 }, }; /* display-if * * display interface clock, divided from esysclk */ static struct clksrc_clk clk_display = { .clk = { .name = "display-if", .id = -1, .parent = &clk_esysclk.clk, .ctrlbit = S3C2443_SCLKCON_DISPCLK, .enable = s3c2443_clkcon_enable_s, }, .reg_div = { .reg = S3C2443_CLKDIV1, .size = 8, .shift = 16 }, }; /* prediv * * this divides the msysclk down to pass to h/p/etc. */ static unsigned long s3c2443_prediv_getrate(struct clk *clk) { unsigned long rate = clk_get_rate(clk->parent); unsigned long clkdiv0 = __raw_readl(S3C2443_CLKDIV0); clkdiv0 &= S3C2443_CLKDIV0_PREDIV_MASK; clkdiv0 >>= S3C2443_CLKDIV0_PREDIV_SHIFT; return rate / (clkdiv0 + 1); } static struct clk clk_prediv = { .name = "prediv", .id = -1, .parent = &clk_msysclk.clk, .ops = &(struct clk_ops) { .get_rate = s3c2443_prediv_getrate, }, }; /* standard clock definitions */ static struct clk init_clocks_off[] = { { .name = "nand", .id = -1, .parent = &clk_h, }, { .name = "sdi", .id = -1, .parent = &clk_p, .enable = s3c2443_clkcon_enable_p, .ctrlbit = S3C2443_PCLKCON_SDI, }, { .name = "adc", .id = -1, .parent = &clk_p, .enable = s3c2443_clkcon_enable_p, .ctrlbit = S3C2443_PCLKCON_ADC, }, { .name = "i2c", .id = -1, .parent = &clk_p, .enable = s3c2443_clkcon_enable_p, .ctrlbit = S3C2443_PCLKCON_IIC, }, { .name = "iis", .id = -1, .parent = &clk_p, .enable = s3c2443_clkcon_enable_p, .ctrlbit = S3C2443_PCLKCON_IIS, }, { .name = "spi", .id = 0, .parent = &clk_p, .enable = s3c2443_clkcon_enable_p, .ctrlbit = S3C2443_PCLKCON_SPI0, }, { .name = "spi", .id = 1, .parent = &clk_p, .enable = s3c2443_clkcon_enable_p, .ctrlbit = S3C2443_PCLKCON_SPI1, } }; static struct clk init_clocks[] = { { .name = "dma", .id = 0, .parent = &clk_h, .enable = s3c2443_clkcon_enable_h, .ctrlbit = S3C2443_HCLKCON_DMA0, }, { .name = "dma", .id = 1, .parent = &clk_h, .enable = s3c2443_clkcon_enable_h, .ctrlbit = S3C2443_HCLKCON_DMA1, }, { .name = "dma", .id = 2, .parent = &clk_h, .enable = s3c2443_clkcon_enable_h, .ctrlbit = S3C2443_HCLKCON_DMA2, }, { .name = "dma", .id = 3, .parent = &clk_h, .enable = s3c2443_clkcon_enable_h, .ctrlbit = S3C2443_HCLKCON_DMA3, }, { .name = "dma", .id = 4, .parent = &clk_h, .enable = s3c2443_clkcon_enable_h, .ctrlbit = S3C2443_HCLKCON_DMA4, }, { .name = "dma", .id = 5, .parent = &clk_h, .enable = s3c2443_clkcon_enable_h, .ctrlbit = S3C2443_HCLKCON_DMA5, }, { .name = "lcd", .id = -1, .parent = &clk_h, .enable = s3c2443_clkcon_enable_h, .ctrlbit = S3C2443_HCLKCON_LCDC, }, { .name = "gpio", .id = -1, .parent = &clk_p, .enable = s3c2443_clkcon_enable_p, .ctrlbit = S3C2443_PCLKCON_GPIO, }, { .name = "usb-host", .id = -1, .parent = &clk_h, .enable = s3c2443_clkcon_enable_h, .ctrlbit = S3C2443_HCLKCON_USBH, }, { .name = "usb-device", .id = -1, .parent = &clk_h, .enable = s3c2443_clkcon_enable_h, .ctrlbit = S3C2443_HCLKCON_USBD, }, { .name = "hsmmc", .id = -1, .parent = &clk_h, .enable = s3c2443_clkcon_enable_h, .ctrlbit = S3C2443_HCLKCON_HSMMC, }, { .name = "cfc", .id = -1, .parent = &clk_h, .enable = s3c2443_clkcon_enable_h, .ctrlbit = S3C2443_HCLKCON_CFC, }, { .name = "ssmc", .id = -1, .parent = &clk_h, .enable = s3c2443_clkcon_enable_h, .ctrlbit = S3C2443_HCLKCON_SSMC, }, { .name = "timers", .id = -1, .parent = &clk_p, .enable = s3c2443_clkcon_enable_p, .ctrlbit = S3C2443_PCLKCON_PWMT, }, { .name = "uart", .id = 0, .parent = &clk_p, .enable = s3c2443_clkcon_enable_p, .ctrlbit = S3C2443_PCLKCON_UART0, }, { .name = "uart", .id = 1, .parent = &clk_p, .enable = s3c2443_clkcon_enable_p, .ctrlbit = S3C2443_PCLKCON_UART1, }, { .name = "uart", .id = 2, .parent = &clk_p, .enable = s3c2443_clkcon_enable_p, .ctrlbit = S3C2443_PCLKCON_UART2, }, { .name = "uart", .id = 3, .parent = &clk_p, .enable = s3c2443_clkcon_enable_p, .ctrlbit = S3C2443_PCLKCON_UART3, }, { .name = "rtc", .id = -1, .parent = &clk_p, .enable = s3c2443_clkcon_enable_p, .ctrlbit = S3C2443_PCLKCON_RTC, }, { .name = "watchdog", .id = -1, .parent = &clk_p, .ctrlbit = S3C2443_PCLKCON_WDT, }, { .name = "usb-bus-host", .id = -1, .parent = &clk_usb_bus_host.clk, }, { .name = "ac97", .id = -1, .parent = &clk_p, .ctrlbit = S3C2443_PCLKCON_AC97, } }; /* clocks to add where we need to check their parentage */ static struct clksrc_clk __initdata *init_list[] = { &clk_epllref, /* should be first */ &clk_esysclk, &clk_msysclk, &clk_arm, &clk_i2s_eplldiv, &clk_i2s, &clk_cam, &clk_uart, &clk_display, &clk_hsmmc_div, &clk_usb_bus_host, }; static void __init s3c2443_clk_initparents(void) { int ptr; for (ptr = 0; ptr < ARRAY_SIZE(init_list); ptr++) s3c_set_clksrc(init_list[ptr], true); } static inline unsigned long s3c2443_get_hdiv(unsigned long clkcon0) { clkcon0 &= S3C2443_CLKDIV0_HCLKDIV_MASK; return clkcon0 + 1; } /* clocks to add straight away */ static struct clksrc_clk *clksrcs[] __initdata = { &clk_usb_bus_host, &clk_epllref, &clk_esysclk, &clk_msysclk, &clk_arm, &clk_uart, &clk_display, &clk_cam, &clk_i2s_eplldiv, &clk_i2s, &clk_hsspi, &clk_hsmmc_div, }; static struct clk *clks[] __initdata = { &clk_ext, &clk_epll, &clk_usb_bus, &clk_mpllref, &clk_hsmmc, &clk_armdiv, &clk_prediv, }; void __init_or_cpufreq s3c2443_setup_clocks(void) { unsigned long mpllcon = __raw_readl(S3C2443_MPLLCON); unsigned long clkdiv0 = __raw_readl(S3C2443_CLKDIV0); struct clk *xtal_clk; unsigned long xtal; unsigned long pll; unsigned long fclk; unsigned long hclk; unsigned long pclk; xtal_clk = clk_get(NULL, "xtal"); xtal = clk_get_rate(xtal_clk); clk_put(xtal_clk); pll = s3c2443_get_mpll(mpllcon, xtal); clk_msysclk.clk.rate = pll; fclk = pll / s3c2443_fclk_div(clkdiv0); hclk = s3c2443_prediv_getrate(&clk_prediv); hclk /= s3c2443_get_hdiv(clkdiv0); pclk = hclk / ((clkdiv0 & S3C2443_CLKDIV0_HALF_PCLK) ? 2 : 1); s3c24xx_setup_clocks(fclk, hclk, pclk); printk("S3C2443: mpll %s %ld.%03ld MHz, cpu %ld.%03ld MHz, mem %ld.%03ld MHz, pclk %ld.%03ld MHz\n", (mpllcon & S3C2443_PLLCON_OFF) ? "off":"on", print_mhz(pll), print_mhz(fclk), print_mhz(hclk), print_mhz(pclk)); s3c24xx_setup_clocks(fclk, hclk, pclk); } void __init s3c2443_init_clocks(int xtal) { unsigned long epllcon = __raw_readl(S3C2443_EPLLCON); int ptr; /* s3c2443 parents h and p clocks from prediv */ clk_h.parent = &clk_prediv; clk_p.parent = &clk_prediv; s3c24xx_register_baseclocks(xtal); s3c2443_setup_clocks(); s3c2443_clk_initparents(); s3c24xx_register_clocks(clks, ARRAY_SIZE(clks)); for (ptr = 0; ptr < ARRAY_SIZE(clksrcs); ptr++) s3c_register_clksrc(clksrcs[ptr], 1); clk_epll.rate = s3c2443_get_epll(epllcon, xtal); clk_epll.parent = &clk_epllref.clk; clk_usb_bus.parent = &clk_usb_bus_host.clk; /* ensure usb bus clock is within correct rate of 48MHz */ if (clk_get_rate(&clk_usb_bus_host.clk) != (48 * 1000 * 1000)) { printk(KERN_INFO "Warning: USB host bus not at 48MHz\n"); clk_set_rate(&clk_usb_bus_host.clk, 48*1000*1000); } printk("S3C2443: epll %s %ld.%03ld MHz, usb-bus %ld.%03ld MHz\n", (epllcon & S3C2443_PLLCON_OFF) ? "off":"on", print_mhz(clk_get_rate(&clk_epll)), print_mhz(clk_get_rate(&clk_usb_bus))); /* register clocks from clock array */ s3c_register_clocks(init_clocks, ARRAY_SIZE(init_clocks)); /* We must be careful disabling the clocks we are not intending to * be using at boot time, as subsystems such as the LCD which do * their own DMA requests to the bus can cause the system to lockup * if they where in the middle of requesting bus access. * * Disabling the LCD clock if the LCD is active is very dangerous, * and therefore the bootloader should be careful to not enable * the LCD clock if it is not needed. */ /* install (and disable) the clocks we do not need immediately */ s3c_register_clocks(init_clocks_off, ARRAY_SIZE(init_clocks_off)); s3c_disable_clocks(init_clocks_off, ARRAY_SIZE(init_clocks_off)); s3c_pwmclk_init(); }