diff options
Diffstat (limited to 'drivers/clk/clk-aspeed.c')
| -rw-r--r-- | drivers/clk/clk-aspeed.c | 742 |
1 files changed, 742 insertions, 0 deletions
diff --git a/drivers/clk/clk-aspeed.c b/drivers/clk/clk-aspeed.c new file mode 100644 index 000000000..411ff5fb2 --- /dev/null +++ b/drivers/clk/clk-aspeed.c @@ -0,0 +1,742 @@ +// SPDX-License-Identifier: GPL-2.0+ +// Copyright IBM Corp + +#define pr_fmt(fmt) "clk-aspeed: " fmt + +#include <linux/mfd/syscon.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/slab.h> + +#include <dt-bindings/clock/aspeed-clock.h> + +#include "clk-aspeed.h" + +#define ASPEED_NUM_CLKS 38 + +#define ASPEED_RESET2_OFFSET 32 + +#define ASPEED_RESET_CTRL 0x04 +#define ASPEED_CLK_SELECTION 0x08 +#define ASPEED_CLK_STOP_CTRL 0x0c +#define ASPEED_MPLL_PARAM 0x20 +#define ASPEED_HPLL_PARAM 0x24 +#define AST2500_HPLL_BYPASS_EN BIT(20) +#define AST2400_HPLL_PROGRAMMED BIT(18) +#define AST2400_HPLL_BYPASS_EN BIT(17) +#define ASPEED_MISC_CTRL 0x2c +#define UART_DIV13_EN BIT(12) +#define ASPEED_MAC_CLK_DLY 0x48 +#define ASPEED_STRAP 0x70 +#define CLKIN_25MHZ_EN BIT(23) +#define AST2400_CLK_SOURCE_SEL BIT(18) +#define ASPEED_CLK_SELECTION_2 0xd8 +#define ASPEED_RESET_CTRL2 0xd4 + +/* Globally visible clocks */ +static DEFINE_SPINLOCK(aspeed_clk_lock); + +/* Keeps track of all clocks */ +static struct clk_hw_onecell_data *aspeed_clk_data; + +static void __iomem *scu_base; + +/* TODO: ask Aspeed about the actual parent data */ +static const struct aspeed_gate_data aspeed_gates[] = { + /* clk rst name parent flags */ + [ASPEED_CLK_GATE_ECLK] = { 0, 6, "eclk-gate", "eclk", 0 }, /* Video Engine */ + [ASPEED_CLK_GATE_GCLK] = { 1, 7, "gclk-gate", NULL, 0 }, /* 2D engine */ + [ASPEED_CLK_GATE_MCLK] = { 2, -1, "mclk-gate", "mpll", CLK_IS_CRITICAL }, /* SDRAM */ + [ASPEED_CLK_GATE_VCLK] = { 3, -1, "vclk-gate", NULL, 0 }, /* Video Capture */ + [ASPEED_CLK_GATE_BCLK] = { 4, 8, "bclk-gate", "bclk", CLK_IS_CRITICAL }, /* PCIe/PCI */ + [ASPEED_CLK_GATE_DCLK] = { 5, -1, "dclk-gate", NULL, CLK_IS_CRITICAL }, /* DAC */ + [ASPEED_CLK_GATE_REFCLK] = { 6, -1, "refclk-gate", "clkin", CLK_IS_CRITICAL }, + [ASPEED_CLK_GATE_USBPORT2CLK] = { 7, 3, "usb-port2-gate", NULL, 0 }, /* USB2.0 Host port 2 */ + [ASPEED_CLK_GATE_LCLK] = { 8, 5, "lclk-gate", NULL, 0 }, /* LPC */ + [ASPEED_CLK_GATE_USBUHCICLK] = { 9, 15, "usb-uhci-gate", NULL, 0 }, /* USB1.1 (requires port 2 enabled) */ + [ASPEED_CLK_GATE_D1CLK] = { 10, 13, "d1clk-gate", NULL, 0 }, /* GFX CRT */ + [ASPEED_CLK_GATE_YCLK] = { 13, 4, "yclk-gate", NULL, 0 }, /* HAC */ + [ASPEED_CLK_GATE_USBPORT1CLK] = { 14, 14, "usb-port1-gate", NULL, 0 }, /* USB2 hub/USB2 host port 1/USB1.1 dev */ + [ASPEED_CLK_GATE_UART1CLK] = { 15, -1, "uart1clk-gate", "uart", 0 }, /* UART1 */ + [ASPEED_CLK_GATE_UART2CLK] = { 16, -1, "uart2clk-gate", "uart", 0 }, /* UART2 */ + [ASPEED_CLK_GATE_UART5CLK] = { 17, -1, "uart5clk-gate", "uart", 0 }, /* UART5 */ + [ASPEED_CLK_GATE_ESPICLK] = { 19, -1, "espiclk-gate", NULL, 0 }, /* eSPI */ + [ASPEED_CLK_GATE_MAC1CLK] = { 20, 11, "mac1clk-gate", "mac", 0 }, /* MAC1 */ + [ASPEED_CLK_GATE_MAC2CLK] = { 21, 12, "mac2clk-gate", "mac", 0 }, /* MAC2 */ + [ASPEED_CLK_GATE_RSACLK] = { 24, -1, "rsaclk-gate", NULL, 0 }, /* RSA */ + [ASPEED_CLK_GATE_UART3CLK] = { 25, -1, "uart3clk-gate", "uart", 0 }, /* UART3 */ + [ASPEED_CLK_GATE_UART4CLK] = { 26, -1, "uart4clk-gate", "uart", 0 }, /* UART4 */ + [ASPEED_CLK_GATE_SDCLK] = { 27, 16, "sdclk-gate", NULL, 0 }, /* SDIO/SD */ + [ASPEED_CLK_GATE_LHCCLK] = { 28, -1, "lhclk-gate", "lhclk", 0 }, /* LPC master/LPC+ */ +}; + +static const char * const eclk_parent_names[] = { + "mpll", + "hpll", + "dpll", +}; + +static const struct clk_div_table ast2500_eclk_div_table[] = { + { 0x0, 2 }, + { 0x1, 2 }, + { 0x2, 3 }, + { 0x3, 4 }, + { 0x4, 5 }, + { 0x5, 6 }, + { 0x6, 7 }, + { 0x7, 8 }, + { 0 } +}; + +static const struct clk_div_table ast2500_mac_div_table[] = { + { 0x0, 4 }, /* Yep, really. Aspeed confirmed this is correct */ + { 0x1, 4 }, + { 0x2, 6 }, + { 0x3, 8 }, + { 0x4, 10 }, + { 0x5, 12 }, + { 0x6, 14 }, + { 0x7, 16 }, + { 0 } +}; + +static const struct clk_div_table ast2400_div_table[] = { + { 0x0, 2 }, + { 0x1, 4 }, + { 0x2, 6 }, + { 0x3, 8 }, + { 0x4, 10 }, + { 0x5, 12 }, + { 0x6, 14 }, + { 0x7, 16 }, + { 0 } +}; + +static const struct clk_div_table ast2500_div_table[] = { + { 0x0, 4 }, + { 0x1, 8 }, + { 0x2, 12 }, + { 0x3, 16 }, + { 0x4, 20 }, + { 0x5, 24 }, + { 0x6, 28 }, + { 0x7, 32 }, + { 0 } +}; + +static struct clk_hw *aspeed_ast2400_calc_pll(const char *name, u32 val) +{ + unsigned int mult, div; + + if (val & AST2400_HPLL_BYPASS_EN) { + /* Pass through mode */ + mult = div = 1; + } else { + /* F = 24Mhz * (2-OD) * [(N + 2) / (D + 1)] */ + u32 n = (val >> 5) & 0x3f; + u32 od = (val >> 4) & 0x1; + u32 d = val & 0xf; + + mult = (2 - od) * (n + 2); + div = d + 1; + } + return clk_hw_register_fixed_factor(NULL, name, "clkin", 0, + mult, div); +}; + +static struct clk_hw *aspeed_ast2500_calc_pll(const char *name, u32 val) +{ + unsigned int mult, div; + + if (val & AST2500_HPLL_BYPASS_EN) { + /* Pass through mode */ + mult = div = 1; + } else { + /* F = clkin * [(M+1) / (N+1)] / (P + 1) */ + u32 p = (val >> 13) & 0x3f; + u32 m = (val >> 5) & 0xff; + u32 n = val & 0x1f; + + mult = (m + 1) / (n + 1); + div = p + 1; + } + + return clk_hw_register_fixed_factor(NULL, name, "clkin", 0, + mult, div); +} + +static const struct aspeed_clk_soc_data ast2500_data = { + .div_table = ast2500_div_table, + .eclk_div_table = ast2500_eclk_div_table, + .mac_div_table = ast2500_mac_div_table, + .calc_pll = aspeed_ast2500_calc_pll, +}; + +static const struct aspeed_clk_soc_data ast2400_data = { + .div_table = ast2400_div_table, + .eclk_div_table = ast2400_div_table, + .mac_div_table = ast2400_div_table, + .calc_pll = aspeed_ast2400_calc_pll, +}; + +static int aspeed_clk_is_enabled(struct clk_hw *hw) +{ + struct aspeed_clk_gate *gate = to_aspeed_clk_gate(hw); + u32 clk = BIT(gate->clock_idx); + u32 rst = BIT(gate->reset_idx); + u32 enval = (gate->flags & CLK_GATE_SET_TO_DISABLE) ? 0 : clk; + u32 reg; + + /* + * If the IP is in reset, treat the clock as not enabled, + * this happens with some clocks such as the USB one when + * coming from cold reset. Without this, aspeed_clk_enable() + * will fail to lift the reset. + */ + if (gate->reset_idx >= 0) { + regmap_read(gate->map, ASPEED_RESET_CTRL, ®); + if (reg & rst) + return 0; + } + + regmap_read(gate->map, ASPEED_CLK_STOP_CTRL, ®); + + return ((reg & clk) == enval) ? 1 : 0; +} + +static int aspeed_clk_enable(struct clk_hw *hw) +{ + struct aspeed_clk_gate *gate = to_aspeed_clk_gate(hw); + unsigned long flags; + u32 clk = BIT(gate->clock_idx); + u32 rst = BIT(gate->reset_idx); + u32 enval; + + spin_lock_irqsave(gate->lock, flags); + + if (aspeed_clk_is_enabled(hw)) { + spin_unlock_irqrestore(gate->lock, flags); + return 0; + } + + if (gate->reset_idx >= 0) { + /* Put IP in reset */ + regmap_update_bits(gate->map, ASPEED_RESET_CTRL, rst, rst); + + /* Delay 100us */ + udelay(100); + } + + /* Enable clock */ + enval = (gate->flags & CLK_GATE_SET_TO_DISABLE) ? 0 : clk; + regmap_update_bits(gate->map, ASPEED_CLK_STOP_CTRL, clk, enval); + + if (gate->reset_idx >= 0) { + /* A delay of 10ms is specified by the ASPEED docs */ + mdelay(10); + + /* Take IP out of reset */ + regmap_update_bits(gate->map, ASPEED_RESET_CTRL, rst, 0); + } + + spin_unlock_irqrestore(gate->lock, flags); + + return 0; +} + +static void aspeed_clk_disable(struct clk_hw *hw) +{ + struct aspeed_clk_gate *gate = to_aspeed_clk_gate(hw); + unsigned long flags; + u32 clk = BIT(gate->clock_idx); + u32 enval; + + spin_lock_irqsave(gate->lock, flags); + + enval = (gate->flags & CLK_GATE_SET_TO_DISABLE) ? clk : 0; + regmap_update_bits(gate->map, ASPEED_CLK_STOP_CTRL, clk, enval); + + spin_unlock_irqrestore(gate->lock, flags); +} + +static const struct clk_ops aspeed_clk_gate_ops = { + .enable = aspeed_clk_enable, + .disable = aspeed_clk_disable, + .is_enabled = aspeed_clk_is_enabled, +}; + +static const u8 aspeed_resets[] = { + /* SCU04 resets */ + [ASPEED_RESET_XDMA] = 25, + [ASPEED_RESET_MCTP] = 24, + [ASPEED_RESET_ADC] = 23, + [ASPEED_RESET_JTAG_MASTER] = 22, + [ASPEED_RESET_MIC] = 18, + [ASPEED_RESET_PWM] = 9, + [ASPEED_RESET_PECI] = 10, + [ASPEED_RESET_I2C] = 2, + [ASPEED_RESET_AHB] = 1, + + /* + * SCUD4 resets start at an offset to separate them from + * the SCU04 resets. + */ + [ASPEED_RESET_CRT1] = ASPEED_RESET2_OFFSET + 5, +}; + +static int aspeed_reset_deassert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct aspeed_reset *ar = to_aspeed_reset(rcdev); + u32 reg = ASPEED_RESET_CTRL; + u32 bit = aspeed_resets[id]; + + if (bit >= ASPEED_RESET2_OFFSET) { + bit -= ASPEED_RESET2_OFFSET; + reg = ASPEED_RESET_CTRL2; + } + + return regmap_update_bits(ar->map, reg, BIT(bit), 0); +} + +static int aspeed_reset_assert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct aspeed_reset *ar = to_aspeed_reset(rcdev); + u32 reg = ASPEED_RESET_CTRL; + u32 bit = aspeed_resets[id]; + + if (bit >= ASPEED_RESET2_OFFSET) { + bit -= ASPEED_RESET2_OFFSET; + reg = ASPEED_RESET_CTRL2; + } + + return regmap_update_bits(ar->map, reg, BIT(bit), BIT(bit)); +} + +static int aspeed_reset_status(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct aspeed_reset *ar = to_aspeed_reset(rcdev); + u32 reg = ASPEED_RESET_CTRL; + u32 bit = aspeed_resets[id]; + int ret, val; + + if (bit >= ASPEED_RESET2_OFFSET) { + bit -= ASPEED_RESET2_OFFSET; + reg = ASPEED_RESET_CTRL2; + } + + ret = regmap_read(ar->map, reg, &val); + if (ret) + return ret; + + return !!(val & BIT(bit)); +} + +static const struct reset_control_ops aspeed_reset_ops = { + .assert = aspeed_reset_assert, + .deassert = aspeed_reset_deassert, + .status = aspeed_reset_status, +}; + +static struct clk_hw *aspeed_clk_hw_register_gate(struct device *dev, + const char *name, const char *parent_name, unsigned long flags, + struct regmap *map, u8 clock_idx, u8 reset_idx, + u8 clk_gate_flags, spinlock_t *lock) +{ + struct aspeed_clk_gate *gate; + struct clk_init_data init; + struct clk_hw *hw; + int ret; + + gate = kzalloc(sizeof(*gate), GFP_KERNEL); + if (!gate) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.ops = &aspeed_clk_gate_ops; + init.flags = flags; + init.parent_names = parent_name ? &parent_name : NULL; + init.num_parents = parent_name ? 1 : 0; + + gate->map = map; + gate->clock_idx = clock_idx; + gate->reset_idx = reset_idx; + gate->flags = clk_gate_flags; + gate->lock = lock; + gate->hw.init = &init; + + hw = &gate->hw; + ret = clk_hw_register(dev, hw); + if (ret) { + kfree(gate); + hw = ERR_PTR(ret); + } + + return hw; +} + +static int aspeed_clk_probe(struct platform_device *pdev) +{ + const struct aspeed_clk_soc_data *soc_data; + struct device *dev = &pdev->dev; + struct aspeed_reset *ar; + struct regmap *map; + struct clk_hw *hw; + u32 val, rate; + int i, ret; + + map = syscon_node_to_regmap(dev->of_node); + if (IS_ERR(map)) { + dev_err(dev, "no syscon regmap\n"); + return PTR_ERR(map); + } + + ar = devm_kzalloc(dev, sizeof(*ar), GFP_KERNEL); + if (!ar) + return -ENOMEM; + + ar->map = map; + ar->rcdev.owner = THIS_MODULE; + ar->rcdev.nr_resets = ARRAY_SIZE(aspeed_resets); + ar->rcdev.ops = &aspeed_reset_ops; + ar->rcdev.of_node = dev->of_node; + + ret = devm_reset_controller_register(dev, &ar->rcdev); + if (ret) { + dev_err(dev, "could not register reset controller\n"); + return ret; + } + + /* SoC generations share common layouts but have different divisors */ + soc_data = of_device_get_match_data(dev); + if (!soc_data) { + dev_err(dev, "no match data for platform\n"); + return -EINVAL; + } + + /* UART clock div13 setting */ + regmap_read(map, ASPEED_MISC_CTRL, &val); + if (val & UART_DIV13_EN) + rate = 24000000 / 13; + else + rate = 24000000; + /* TODO: Find the parent data for the uart clock */ + hw = clk_hw_register_fixed_rate(dev, "uart", NULL, 0, rate); + if (IS_ERR(hw)) + return PTR_ERR(hw); + aspeed_clk_data->hws[ASPEED_CLK_UART] = hw; + + /* + * Memory controller (M-PLL) PLL. This clock is configured by the + * bootloader, and is exposed to Linux as a read-only clock rate. + */ + regmap_read(map, ASPEED_MPLL_PARAM, &val); + hw = soc_data->calc_pll("mpll", val); + if (IS_ERR(hw)) + return PTR_ERR(hw); + aspeed_clk_data->hws[ASPEED_CLK_MPLL] = hw; + + /* SD/SDIO clock divider and gate */ + hw = clk_hw_register_gate(dev, "sd_extclk_gate", "hpll", 0, + scu_base + ASPEED_CLK_SELECTION, 15, 0, + &aspeed_clk_lock); + if (IS_ERR(hw)) + return PTR_ERR(hw); + hw = clk_hw_register_divider_table(dev, "sd_extclk", "sd_extclk_gate", + 0, scu_base + ASPEED_CLK_SELECTION, 12, 3, 0, + soc_data->div_table, + &aspeed_clk_lock); + if (IS_ERR(hw)) + return PTR_ERR(hw); + aspeed_clk_data->hws[ASPEED_CLK_SDIO] = hw; + + /* MAC AHB bus clock divider */ + hw = clk_hw_register_divider_table(dev, "mac", "hpll", 0, + scu_base + ASPEED_CLK_SELECTION, 16, 3, 0, + soc_data->mac_div_table, + &aspeed_clk_lock); + if (IS_ERR(hw)) + return PTR_ERR(hw); + aspeed_clk_data->hws[ASPEED_CLK_MAC] = hw; + + if (of_device_is_compatible(pdev->dev.of_node, "aspeed,ast2500-scu")) { + /* RMII 50MHz RCLK */ + hw = clk_hw_register_fixed_rate(dev, "mac12rclk", "hpll", 0, + 50000000); + if (IS_ERR(hw)) + return PTR_ERR(hw); + + /* RMII1 50MHz (RCLK) output enable */ + hw = clk_hw_register_gate(dev, "mac1rclk", "mac12rclk", 0, + scu_base + ASPEED_MAC_CLK_DLY, 29, 0, + &aspeed_clk_lock); + if (IS_ERR(hw)) + return PTR_ERR(hw); + aspeed_clk_data->hws[ASPEED_CLK_MAC1RCLK] = hw; + + /* RMII2 50MHz (RCLK) output enable */ + hw = clk_hw_register_gate(dev, "mac2rclk", "mac12rclk", 0, + scu_base + ASPEED_MAC_CLK_DLY, 30, 0, + &aspeed_clk_lock); + if (IS_ERR(hw)) + return PTR_ERR(hw); + aspeed_clk_data->hws[ASPEED_CLK_MAC2RCLK] = hw; + } + + /* LPC Host (LHCLK) clock divider */ + hw = clk_hw_register_divider_table(dev, "lhclk", "hpll", 0, + scu_base + ASPEED_CLK_SELECTION, 20, 3, 0, + soc_data->div_table, + &aspeed_clk_lock); + if (IS_ERR(hw)) + return PTR_ERR(hw); + aspeed_clk_data->hws[ASPEED_CLK_LHCLK] = hw; + + /* P-Bus (BCLK) clock divider */ + hw = clk_hw_register_divider_table(dev, "bclk", "hpll", 0, + scu_base + ASPEED_CLK_SELECTION_2, 0, 2, 0, + soc_data->div_table, + &aspeed_clk_lock); + if (IS_ERR(hw)) + return PTR_ERR(hw); + aspeed_clk_data->hws[ASPEED_CLK_BCLK] = hw; + + /* Fixed 24MHz clock */ + hw = clk_hw_register_fixed_rate(NULL, "fixed-24m", "clkin", + 0, 24000000); + if (IS_ERR(hw)) + return PTR_ERR(hw); + aspeed_clk_data->hws[ASPEED_CLK_24M] = hw; + + hw = clk_hw_register_mux(dev, "eclk-mux", eclk_parent_names, + ARRAY_SIZE(eclk_parent_names), 0, + scu_base + ASPEED_CLK_SELECTION, 2, 0x3, 0, + &aspeed_clk_lock); + if (IS_ERR(hw)) + return PTR_ERR(hw); + aspeed_clk_data->hws[ASPEED_CLK_ECLK_MUX] = hw; + + hw = clk_hw_register_divider_table(dev, "eclk", "eclk-mux", 0, + scu_base + ASPEED_CLK_SELECTION, 28, + 3, 0, soc_data->eclk_div_table, + &aspeed_clk_lock); + if (IS_ERR(hw)) + return PTR_ERR(hw); + aspeed_clk_data->hws[ASPEED_CLK_ECLK] = hw; + + /* + * TODO: There are a number of clocks that not included in this driver + * as more information is required: + * D2-PLL + * D-PLL + * YCLK + * RGMII + * RMII + * UART[1..5] clock source mux + */ + + for (i = 0; i < ARRAY_SIZE(aspeed_gates); i++) { + const struct aspeed_gate_data *gd = &aspeed_gates[i]; + u32 gate_flags; + + /* Special case: the USB port 1 clock (bit 14) is always + * working the opposite way from the other ones. + */ + gate_flags = (gd->clock_idx == 14) ? 0 : CLK_GATE_SET_TO_DISABLE; + hw = aspeed_clk_hw_register_gate(dev, + gd->name, + gd->parent_name, + gd->flags, + map, + gd->clock_idx, + gd->reset_idx, + gate_flags, + &aspeed_clk_lock); + if (IS_ERR(hw)) + return PTR_ERR(hw); + aspeed_clk_data->hws[i] = hw; + } + + return 0; +}; + +static const struct of_device_id aspeed_clk_dt_ids[] = { + { .compatible = "aspeed,ast2400-scu", .data = &ast2400_data }, + { .compatible = "aspeed,ast2500-scu", .data = &ast2500_data }, + { } +}; + +static struct platform_driver aspeed_clk_driver = { + .probe = aspeed_clk_probe, + .driver = { + .name = "aspeed-clk", + .of_match_table = aspeed_clk_dt_ids, + .suppress_bind_attrs = true, + }, +}; +builtin_platform_driver(aspeed_clk_driver); + +static void __init aspeed_ast2400_cc(struct regmap *map) +{ + struct clk_hw *hw; + u32 val, div, clkin, hpll; + const u16 hpll_rates[][4] = { + {384, 360, 336, 408}, + {400, 375, 350, 425}, + }; + int rate; + + /* + * CLKIN is the crystal oscillator, 24, 48 or 25MHz selected by + * strapping + */ + regmap_read(map, ASPEED_STRAP, &val); + rate = (val >> 8) & 3; + if (val & CLKIN_25MHZ_EN) { + clkin = 25000000; + hpll = hpll_rates[1][rate]; + } else if (val & AST2400_CLK_SOURCE_SEL) { + clkin = 48000000; + hpll = hpll_rates[0][rate]; + } else { + clkin = 24000000; + hpll = hpll_rates[0][rate]; + } + hw = clk_hw_register_fixed_rate(NULL, "clkin", NULL, 0, clkin); + pr_debug("clkin @%u MHz\n", clkin / 1000000); + + /* + * High-speed PLL clock derived from the crystal. This the CPU clock, + * and we assume that it is enabled. It can be configured through the + * HPLL_PARAM register, or set to a specified frequency by strapping. + */ + regmap_read(map, ASPEED_HPLL_PARAM, &val); + if (val & AST2400_HPLL_PROGRAMMED) + hw = aspeed_ast2400_calc_pll("hpll", val); + else + hw = clk_hw_register_fixed_rate(NULL, "hpll", "clkin", 0, + hpll * 1000000); + + aspeed_clk_data->hws[ASPEED_CLK_HPLL] = hw; + + /* + * Strap bits 11:10 define the CPU/AHB clock frequency ratio (aka HCLK) + * 00: Select CPU:AHB = 1:1 + * 01: Select CPU:AHB = 2:1 + * 10: Select CPU:AHB = 4:1 + * 11: Select CPU:AHB = 3:1 + */ + regmap_read(map, ASPEED_STRAP, &val); + val = (val >> 10) & 0x3; + div = val + 1; + if (div == 3) + div = 4; + else if (div == 4) + div = 3; + hw = clk_hw_register_fixed_factor(NULL, "ahb", "hpll", 0, 1, div); + aspeed_clk_data->hws[ASPEED_CLK_AHB] = hw; + + /* APB clock clock selection register SCU08 (aka PCLK) */ + hw = clk_hw_register_divider_table(NULL, "apb", "hpll", 0, + scu_base + ASPEED_CLK_SELECTION, 23, 3, 0, + ast2400_div_table, + &aspeed_clk_lock); + aspeed_clk_data->hws[ASPEED_CLK_APB] = hw; +} + +static void __init aspeed_ast2500_cc(struct regmap *map) +{ + struct clk_hw *hw; + u32 val, freq, div; + + /* CLKIN is the crystal oscillator, 24 or 25MHz selected by strapping */ + regmap_read(map, ASPEED_STRAP, &val); + if (val & CLKIN_25MHZ_EN) + freq = 25000000; + else + freq = 24000000; + hw = clk_hw_register_fixed_rate(NULL, "clkin", NULL, 0, freq); + pr_debug("clkin @%u MHz\n", freq / 1000000); + + /* + * High-speed PLL clock derived from the crystal. This the CPU clock, + * and we assume that it is enabled + */ + regmap_read(map, ASPEED_HPLL_PARAM, &val); + aspeed_clk_data->hws[ASPEED_CLK_HPLL] = aspeed_ast2500_calc_pll("hpll", val); + + /* Strap bits 11:9 define the AXI/AHB clock frequency ratio (aka HCLK)*/ + regmap_read(map, ASPEED_STRAP, &val); + val = (val >> 9) & 0x7; + WARN(val == 0, "strapping is zero: cannot determine ahb clock"); + div = 2 * (val + 1); + hw = clk_hw_register_fixed_factor(NULL, "ahb", "hpll", 0, 1, div); + aspeed_clk_data->hws[ASPEED_CLK_AHB] = hw; + + /* APB clock clock selection register SCU08 (aka PCLK) */ + regmap_read(map, ASPEED_CLK_SELECTION, &val); + val = (val >> 23) & 0x7; + div = 4 * (val + 1); + hw = clk_hw_register_fixed_factor(NULL, "apb", "hpll", 0, 1, div); + aspeed_clk_data->hws[ASPEED_CLK_APB] = hw; +}; + +static void __init aspeed_cc_init(struct device_node *np) +{ + struct regmap *map; + u32 val; + int ret; + int i; + + scu_base = of_iomap(np, 0); + if (!scu_base) + return; + + aspeed_clk_data = kzalloc(struct_size(aspeed_clk_data, hws, + ASPEED_NUM_CLKS), + GFP_KERNEL); + if (!aspeed_clk_data) + return; + + /* + * This way all clocks fetched before the platform device probes, + * except those we assign here for early use, will be deferred. + */ + for (i = 0; i < ASPEED_NUM_CLKS; i++) + aspeed_clk_data->hws[i] = ERR_PTR(-EPROBE_DEFER); + + map = syscon_node_to_regmap(np); + if (IS_ERR(map)) { + pr_err("no syscon regmap\n"); + return; + } + /* + * We check that the regmap works on this very first access, + * but as this is an MMIO-backed regmap, subsequent regmap + * access is not going to fail and we skip error checks from + * this point. + */ + ret = regmap_read(map, ASPEED_STRAP, &val); + if (ret) { + pr_err("failed to read strapping register\n"); + return; + } + + if (of_device_is_compatible(np, "aspeed,ast2400-scu")) + aspeed_ast2400_cc(map); + else if (of_device_is_compatible(np, "aspeed,ast2500-scu")) + aspeed_ast2500_cc(map); + else + pr_err("unknown platform, failed to add clocks\n"); + + aspeed_clk_data->num = ASPEED_NUM_CLKS; + ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, aspeed_clk_data); + if (ret) + pr_err("failed to add DT provider: %d\n", ret); +}; +CLK_OF_DECLARE_DRIVER(aspeed_cc_g5, "aspeed,ast2500-scu", aspeed_cc_init); +CLK_OF_DECLARE_DRIVER(aspeed_cc_g4, "aspeed,ast2400-scu", aspeed_cc_init); |