diff options
Diffstat (limited to 'roms/u-boot/drivers/clk/aspeed/clk_ast2500.c')
-rw-r--r-- | roms/u-boot/drivers/clk/aspeed/clk_ast2500.c | 531 |
1 files changed, 531 insertions, 0 deletions
diff --git a/roms/u-boot/drivers/clk/aspeed/clk_ast2500.c b/roms/u-boot/drivers/clk/aspeed/clk_ast2500.c new file mode 100644 index 000000000..97f00f505 --- /dev/null +++ b/roms/u-boot/drivers/clk/aspeed/clk_ast2500.c @@ -0,0 +1,531 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * (C) Copyright 2016 Google, Inc + */ + +#include <common.h> +#include <clk-uclass.h> +#include <dm.h> +#include <log.h> +#include <asm/global_data.h> +#include <asm/io.h> +#include <asm/arch/scu_ast2500.h> +#include <dm/lists.h> +#include <dt-bindings/clock/aspeed-clock.h> +#include <linux/delay.h> +#include <linux/err.h> + +/* + * MAC Clock Delay settings, taken from Aspeed SDK + */ +#define RGMII_TXCLK_ODLY 8 +#define RMII_RXCLK_IDLY 2 + +/* + * TGMII Clock Duty constants, taken from Aspeed SDK + */ +#define RGMII2_TXCK_DUTY 0x66 +#define RGMII1_TXCK_DUTY 0x64 + +#define D2PLL_DEFAULT_RATE (250 * 1000 * 1000) + +DECLARE_GLOBAL_DATA_PTR; + +/* + * Clock divider/multiplier configuration struct. + * For H-PLL and M-PLL the formula is + * (Output Frequency) = CLKIN * ((M + 1) / (N + 1)) / (P + 1) + * M - Numerator + * N - Denumerator + * P - Post Divider + * They have the same layout in their control register. + * + * D-PLL and D2-PLL have extra divider (OD + 1), which is not + * yet needed and ignored by clock configurations. + */ +struct ast2500_div_config { + unsigned int num; + unsigned int denum; + unsigned int post_div; +}; + +/* + * Get the rate of the M-PLL clock from input clock frequency and + * the value of the M-PLL Parameter Register. + */ +static ulong ast2500_get_mpll_rate(ulong clkin, u32 mpll_reg) +{ + const ulong num = (mpll_reg & SCU_MPLL_NUM_MASK) >> SCU_MPLL_NUM_SHIFT; + const ulong denum = (mpll_reg & SCU_MPLL_DENUM_MASK) + >> SCU_MPLL_DENUM_SHIFT; + const ulong post_div = (mpll_reg & SCU_MPLL_POST_MASK) + >> SCU_MPLL_POST_SHIFT; + + return (clkin * ((num + 1) / (denum + 1))) / (post_div + 1); +} + +/* + * Get the rate of the H-PLL clock from input clock frequency and + * the value of the H-PLL Parameter Register. + */ +static ulong ast2500_get_hpll_rate(ulong clkin, u32 hpll_reg) +{ + const ulong num = (hpll_reg & SCU_HPLL_NUM_MASK) >> SCU_HPLL_NUM_SHIFT; + const ulong denum = (hpll_reg & SCU_HPLL_DENUM_MASK) + >> SCU_HPLL_DENUM_SHIFT; + const ulong post_div = (hpll_reg & SCU_HPLL_POST_MASK) + >> SCU_HPLL_POST_SHIFT; + + return (clkin * ((num + 1) / (denum + 1))) / (post_div + 1); +} + +static ulong ast2500_get_clkin(struct ast2500_scu *scu) +{ + return readl(&scu->hwstrap) & SCU_HWSTRAP_CLKIN_25MHZ + ? 25 * 1000 * 1000 : 24 * 1000 * 1000; +} + +/** + * Get current rate or uart clock + * + * @scu SCU registers + * @uart_index UART index, 1-5 + * + * @return current setting for uart clock rate + */ +static ulong ast2500_get_uart_clk_rate(struct ast2500_scu *scu, int uart_index) +{ + /* + * ast2500 datasheet is very confusing when it comes to UART clocks, + * especially when CLKIN = 25 MHz. The settings are in + * different registers and it is unclear how they interact. + * + * This has only been tested with default settings and CLKIN = 24 MHz. + */ + ulong uart_clkin; + + if (readl(&scu->misc_ctrl2) & + (1 << (uart_index - 1 + SCU_MISC2_UARTCLK_SHIFT))) + uart_clkin = 192 * 1000 * 1000; + else + uart_clkin = 24 * 1000 * 1000; + + if (readl(&scu->misc_ctrl1) & SCU_MISC_UARTCLK_DIV13) + uart_clkin /= 13; + + return uart_clkin; +} + +static ulong ast2500_clk_get_rate(struct clk *clk) +{ + struct ast2500_clk_priv *priv = dev_get_priv(clk->dev); + ulong clkin = ast2500_get_clkin(priv->scu); + ulong rate; + + switch (clk->id) { + case ASPEED_CLK_HPLL: + /* + * This ignores dynamic/static slowdown of ARMCLK and may + * be inaccurate. + */ + rate = ast2500_get_hpll_rate(clkin, + readl(&priv->scu->h_pll_param)); + break; + case ASPEED_CLK_MPLL: + rate = ast2500_get_mpll_rate(clkin, + readl(&priv->scu->m_pll_param)); + break; + case ASPEED_CLK_APB: + { + ulong apb_div = 4 + 4 * ((readl(&priv->scu->clk_sel1) + & SCU_PCLK_DIV_MASK) + >> SCU_PCLK_DIV_SHIFT); + rate = ast2500_get_hpll_rate(clkin, + readl(&priv-> + scu->h_pll_param)); + rate = rate / apb_div; + } + break; + case ASPEED_CLK_SDIO: + { + ulong apb_div = 4 + 4 * ((readl(&priv->scu->clk_sel1) + & SCU_SDCLK_DIV_MASK) + >> SCU_SDCLK_DIV_SHIFT); + rate = ast2500_get_hpll_rate(clkin, + readl(&priv-> + scu->h_pll_param)); + rate = rate / apb_div; + } + break; + case ASPEED_CLK_GATE_UART1CLK: + rate = ast2500_get_uart_clk_rate(priv->scu, 1); + break; + case ASPEED_CLK_GATE_UART2CLK: + rate = ast2500_get_uart_clk_rate(priv->scu, 2); + break; + case ASPEED_CLK_GATE_UART3CLK: + rate = ast2500_get_uart_clk_rate(priv->scu, 3); + break; + case ASPEED_CLK_GATE_UART4CLK: + rate = ast2500_get_uart_clk_rate(priv->scu, 4); + break; + case ASPEED_CLK_GATE_UART5CLK: + rate = ast2500_get_uart_clk_rate(priv->scu, 5); + break; + default: + return -ENOENT; + } + + return rate; +} + +struct ast2500_clock_config { + ulong input_rate; + ulong rate; + struct ast2500_div_config cfg; +}; + +static const struct ast2500_clock_config ast2500_clock_config_defaults[] = { + { 24000000, 250000000, { .num = 124, .denum = 1, .post_div = 5 } }, +}; + +static bool ast2500_get_clock_config_default(ulong input_rate, + ulong requested_rate, + struct ast2500_div_config *cfg) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(ast2500_clock_config_defaults); i++) { + const struct ast2500_clock_config *default_cfg = + &ast2500_clock_config_defaults[i]; + if (default_cfg->input_rate == input_rate && + default_cfg->rate == requested_rate) { + *cfg = default_cfg->cfg; + return true; + } + } + + return false; +} + +/* + * @input_rate - the rate of input clock in Hz + * @requested_rate - desired output rate in Hz + * @div - this is an IN/OUT parameter, at input all fields of the config + * need to be set to their maximum allowed values. + * The result (the best config we could find), would also be returned + * in this structure. + * + * @return The clock rate, when the resulting div_config is used. + */ +static ulong ast2500_calc_clock_config(ulong input_rate, ulong requested_rate, + struct ast2500_div_config *cfg) +{ + /* + * The assumption is that kHz precision is good enough and + * also enough to avoid overflow when multiplying. + */ + const ulong input_rate_khz = input_rate / 1000; + const ulong rate_khz = requested_rate / 1000; + const struct ast2500_div_config max_vals = *cfg; + struct ast2500_div_config it = { 0, 0, 0 }; + ulong delta = rate_khz; + ulong new_rate_khz = 0; + + /* + * Look for a well known frequency first. + */ + if (ast2500_get_clock_config_default(input_rate, requested_rate, cfg)) + return requested_rate; + + for (; it.denum <= max_vals.denum; ++it.denum) { + for (it.post_div = 0; it.post_div <= max_vals.post_div; + ++it.post_div) { + it.num = (rate_khz * (it.post_div + 1) / input_rate_khz) + * (it.denum + 1); + if (it.num > max_vals.num) + continue; + + new_rate_khz = (input_rate_khz + * ((it.num + 1) / (it.denum + 1))) + / (it.post_div + 1); + + /* Keep the rate below requested one. */ + if (new_rate_khz > rate_khz) + continue; + + if (new_rate_khz - rate_khz < delta) { + delta = new_rate_khz - rate_khz; + *cfg = it; + if (delta == 0) + return new_rate_khz * 1000; + } + } + } + + return new_rate_khz * 1000; +} + +static ulong ast2500_configure_ddr(struct ast2500_scu *scu, ulong rate) +{ + ulong clkin = ast2500_get_clkin(scu); + u32 mpll_reg; + struct ast2500_div_config div_cfg = { + .num = (SCU_MPLL_NUM_MASK >> SCU_MPLL_NUM_SHIFT), + .denum = (SCU_MPLL_DENUM_MASK >> SCU_MPLL_DENUM_SHIFT), + .post_div = (SCU_MPLL_POST_MASK >> SCU_MPLL_POST_SHIFT), + }; + + ast2500_calc_clock_config(clkin, rate, &div_cfg); + + mpll_reg = readl(&scu->m_pll_param); + mpll_reg &= ~(SCU_MPLL_POST_MASK | SCU_MPLL_NUM_MASK + | SCU_MPLL_DENUM_MASK); + mpll_reg |= (div_cfg.post_div << SCU_MPLL_POST_SHIFT) + | (div_cfg.num << SCU_MPLL_NUM_SHIFT) + | (div_cfg.denum << SCU_MPLL_DENUM_SHIFT); + + ast_scu_unlock(scu); + writel(mpll_reg, &scu->m_pll_param); + ast_scu_lock(scu); + + return ast2500_get_mpll_rate(clkin, mpll_reg); +} + +static ulong ast2500_configure_mac(struct ast2500_scu *scu, int index) +{ + ulong clkin = ast2500_get_clkin(scu); + ulong hpll_rate = ast2500_get_hpll_rate(clkin, + readl(&scu->h_pll_param)); + ulong required_rate; + u32 hwstrap; + u32 divisor; + u32 reset_bit; + u32 clkstop_bit; + + /* + * According to data sheet, for 10/100 mode the MAC clock frequency + * should be at least 25MHz and for 1000 mode at least 100MHz + */ + hwstrap = readl(&scu->hwstrap); + if (hwstrap & (SCU_HWSTRAP_MAC1_RGMII | SCU_HWSTRAP_MAC2_RGMII)) + required_rate = 100 * 1000 * 1000; + else + required_rate = 25 * 1000 * 1000; + + divisor = hpll_rate / required_rate; + + if (divisor < 4) { + /* Clock can't run fast enough, but let's try anyway */ + debug("MAC clock too slow\n"); + divisor = 4; + } else if (divisor > 16) { + /* Can't slow down the clock enough, but let's try anyway */ + debug("MAC clock too fast\n"); + divisor = 16; + } + + switch (index) { + case 1: + reset_bit = SCU_SYSRESET_MAC1; + clkstop_bit = SCU_CLKSTOP_MAC1; + break; + case 2: + reset_bit = SCU_SYSRESET_MAC2; + clkstop_bit = SCU_CLKSTOP_MAC2; + break; + default: + return -EINVAL; + } + + ast_scu_unlock(scu); + clrsetbits_le32(&scu->clk_sel1, SCU_MACCLK_MASK, + ((divisor - 2) / 2) << SCU_MACCLK_SHIFT); + + /* + * Disable MAC, start its clock and re-enable it. + * The procedure and the delays (100us & 10ms) are + * specified in the datasheet. + */ + setbits_le32(&scu->sysreset_ctrl1, reset_bit); + udelay(100); + clrbits_le32(&scu->clk_stop_ctrl1, clkstop_bit); + mdelay(10); + clrbits_le32(&scu->sysreset_ctrl1, reset_bit); + + writel((RGMII2_TXCK_DUTY << SCU_CLKDUTY_RGMII2TXCK_SHIFT) + | (RGMII1_TXCK_DUTY << SCU_CLKDUTY_RGMII1TXCK_SHIFT), + &scu->clk_duty_sel); + + ast_scu_lock(scu); + + return required_rate; +} + +static ulong ast2500_configure_d2pll(struct ast2500_scu *scu, ulong rate) +{ + /* + * The values and the meaning of the next three + * parameters are undocumented. Taken from Aspeed SDK. + * + * TODO(clg@kaod.org): the SIP and SIC values depend on the + * Numerator value + */ + const u32 d2_pll_ext_param = 0x2c; + const u32 d2_pll_sip = 0x11; + const u32 d2_pll_sic = 0x18; + u32 clk_delay_settings = + (RMII_RXCLK_IDLY << SCU_MICDS_MAC1RMII_RDLY_SHIFT) + | (RMII_RXCLK_IDLY << SCU_MICDS_MAC2RMII_RDLY_SHIFT) + | (RGMII_TXCLK_ODLY << SCU_MICDS_MAC1RGMII_TXDLY_SHIFT) + | (RGMII_TXCLK_ODLY << SCU_MICDS_MAC2RGMII_TXDLY_SHIFT); + struct ast2500_div_config div_cfg = { + .num = SCU_D2PLL_NUM_MASK >> SCU_D2PLL_NUM_SHIFT, + .denum = SCU_D2PLL_DENUM_MASK >> SCU_D2PLL_DENUM_SHIFT, + .post_div = SCU_D2PLL_POST_MASK >> SCU_D2PLL_POST_SHIFT, + }; + ulong clkin = ast2500_get_clkin(scu); + ulong new_rate; + + ast_scu_unlock(scu); + writel((d2_pll_ext_param << SCU_D2PLL_EXT1_PARAM_SHIFT) + | SCU_D2PLL_EXT1_OFF + | SCU_D2PLL_EXT1_RESET, &scu->d2_pll_ext_param[0]); + + /* + * Select USB2.0 port1 PHY clock as a clock source for GCRT. + * This would disconnect it from D2-PLL. + */ + clrsetbits_le32(&scu->misc_ctrl1, SCU_MISC_D2PLL_OFF, + SCU_MISC_GCRT_USB20CLK); + + new_rate = ast2500_calc_clock_config(clkin, rate, &div_cfg); + writel((d2_pll_sip << SCU_D2PLL_SIP_SHIFT) + | (d2_pll_sic << SCU_D2PLL_SIC_SHIFT) + | (div_cfg.num << SCU_D2PLL_NUM_SHIFT) + | (div_cfg.denum << SCU_D2PLL_DENUM_SHIFT) + | (div_cfg.post_div << SCU_D2PLL_POST_SHIFT), + &scu->d2_pll_param); + + clrbits_le32(&scu->d2_pll_ext_param[0], + SCU_D2PLL_EXT1_OFF | SCU_D2PLL_EXT1_RESET); + + clrsetbits_le32(&scu->misc_ctrl2, + SCU_MISC2_RGMII_HPLL | SCU_MISC2_RMII_MPLL + | SCU_MISC2_RGMII_CLKDIV_MASK | + SCU_MISC2_RMII_CLKDIV_MASK, + (4 << SCU_MISC2_RMII_CLKDIV_SHIFT)); + + writel(clk_delay_settings | SCU_MICDS_RGMIIPLL, &scu->mac_clk_delay); + writel(clk_delay_settings, &scu->mac_clk_delay_100M); + writel(clk_delay_settings, &scu->mac_clk_delay_10M); + + ast_scu_lock(scu); + + return new_rate; +} + +static ulong ast2500_clk_set_rate(struct clk *clk, ulong rate) +{ + struct ast2500_clk_priv *priv = dev_get_priv(clk->dev); + + ulong new_rate; + switch (clk->id) { + case ASPEED_CLK_MPLL: + new_rate = ast2500_configure_ddr(priv->scu, rate); + break; + case ASPEED_CLK_D2PLL: + new_rate = ast2500_configure_d2pll(priv->scu, rate); + break; + default: + return -ENOENT; + } + + return new_rate; +} + +static int ast2500_clk_enable(struct clk *clk) +{ + struct ast2500_clk_priv *priv = dev_get_priv(clk->dev); + + switch (clk->id) { + case ASPEED_CLK_SDIO: + if (readl(&priv->scu->clk_stop_ctrl1) & SCU_CLKSTOP_SDCLK) { + ast_scu_unlock(priv->scu); + + setbits_le32(&priv->scu->sysreset_ctrl1, + SCU_SYSRESET_SDIO); + udelay(100); + clrbits_le32(&priv->scu->clk_stop_ctrl1, + SCU_CLKSTOP_SDCLK); + mdelay(10); + clrbits_le32(&priv->scu->sysreset_ctrl1, + SCU_SYSRESET_SDIO); + + ast_scu_lock(priv->scu); + } + break; + /* + * For MAC clocks the clock rate is + * configured based on whether RGMII or RMII mode has been selected + * through hardware strapping. + */ + case ASPEED_CLK_GATE_MAC1CLK: + ast2500_configure_mac(priv->scu, 1); + break; + case ASPEED_CLK_GATE_MAC2CLK: + ast2500_configure_mac(priv->scu, 2); + break; + case ASPEED_CLK_D2PLL: + ast2500_configure_d2pll(priv->scu, D2PLL_DEFAULT_RATE); + break; + default: + return -ENOENT; + } + + return 0; +} + +struct clk_ops ast2500_clk_ops = { + .get_rate = ast2500_clk_get_rate, + .set_rate = ast2500_clk_set_rate, + .enable = ast2500_clk_enable, +}; + +static int ast2500_clk_of_to_plat(struct udevice *dev) +{ + struct ast2500_clk_priv *priv = dev_get_priv(dev); + + priv->scu = devfdt_get_addr_ptr(dev); + if (IS_ERR(priv->scu)) + return PTR_ERR(priv->scu); + + return 0; +} + +static int ast2500_clk_bind(struct udevice *dev) +{ + int ret; + + /* The reset driver does not have a device node, so bind it here */ + ret = device_bind_driver(gd->dm_root, "ast_sysreset", "reset", &dev); + if (ret) + debug("Warning: No reset driver: ret=%d\n", ret); + + return 0; +} + +static const struct udevice_id ast2500_clk_ids[] = { + { .compatible = "aspeed,ast2500-scu" }, + { } +}; + +U_BOOT_DRIVER(aspeed_ast2500_scu) = { + .name = "aspeed_ast2500_scu", + .id = UCLASS_CLK, + .of_match = ast2500_clk_ids, + .priv_auto = sizeof(struct ast2500_clk_priv), + .ops = &ast2500_clk_ops, + .bind = ast2500_clk_bind, + .of_to_plat = ast2500_clk_of_to_plat, +}; |