diff options
Diffstat (limited to 'drivers/clk/clk-aspeed.c')
-rw-r--r-- | drivers/clk/clk-aspeed.c | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/drivers/clk/clk-aspeed.c b/drivers/clk/clk-aspeed.c new file mode 100644 index 000000000000..7a86ee08ea4f --- /dev/null +++ b/drivers/clk/clk-aspeed.c @@ -0,0 +1,141 @@ +// SPDX-License-Identifier: GPL-2.0+ + +#define pr_fmt(fmt) "clk-aspeed: " fmt + +#include <linux/clk-provider.h> +#include <linux/mfd/syscon.h> +#include <linux/of_address.h> +#include <linux/regmap.h> +#include <linux/slab.h> +#include <linux/spinlock.h> + +#include <dt-bindings/clock/aspeed-clock.h> + +#define ASPEED_NUM_CLKS 35 + +#define ASPEED_STRAP 0x70 + +/* Keeps track of all clocks */ +static struct clk_hw_onecell_data *aspeed_clk_data; + +static void __iomem *scu_base; + +/** + * struct aspeed_gate_data - Aspeed gated clocks + * @clock_idx: bit used to gate this clock in the clock register + * @reset_idx: bit used to reset this IP in the reset register. -1 if no + * reset is required when enabling the clock + * @name: the clock name + * @parent_name: the name of the parent clock + * @flags: standard clock framework flags + */ +struct aspeed_gate_data { + u8 clock_idx; + s8 reset_idx; + const char *name; + const char *parent_name; + unsigned long flags; +}; + +/** + * struct aspeed_clk_gate - Aspeed specific clk_gate structure + * @hw: handle between common and hardware-specific interfaces + * @reg: register controlling gate + * @clock_idx: bit used to gate this clock in the clock register + * @reset_idx: bit used to reset this IP in the reset register. -1 if no + * reset is required when enabling the clock + * @flags: hardware-specific flags + * @lock: register lock + * + * Some of the clocks in the Aspeed SoC must be put in reset before enabling. + * This modified version of clk_gate allows an optional reset bit to be + * specified. + */ +struct aspeed_clk_gate { + struct clk_hw hw; + struct regmap *map; + u8 clock_idx; + s8 reset_idx; + u8 flags; + spinlock_t *lock; +}; + +#define to_aspeed_clk_gate(_hw) container_of(_hw, struct aspeed_clk_gate, hw) + +/* 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, -1, "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, 6, "vclk-gate", NULL, 0 }, /* Video Capture */ + [ASPEED_CLK_GATE_BCLK] = { 4, 10, "bclk-gate", "bclk", 0 }, /* PCIe/PCI */ + [ASPEED_CLK_GATE_DCLK] = { 5, -1, "dclk-gate", NULL, 0 }, /* 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_SDCLKCLK] = { 27, 16, "sdclk-gate", NULL, 0 }, /* SDIO/SD */ + [ASPEED_CLK_GATE_LHCCLK] = { 28, -1, "lhclk-gate", "lhclk", 0 }, /* LPC master/LPC+ */ +}; + +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 (IS_ERR(scu_base)) + return; + + aspeed_clk_data = kzalloc(sizeof(*aspeed_clk_data) + + sizeof(*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; + } + + 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); |