[PATCH v7 1/5] clk: Add clock driver for ASPEED BMC SoCs
Benjamin Herrenschmidt
benh at kernel.crashing.org
Mon Jan 1 21:48:45 PST 2018
On Fri, 2017-12-22 at 13:15 +1030, Joel Stanley wrote:
> This adds the stub of a driver for the ASPEED SoCs. The clocks are
> defined and the static registration is set up.
>
> Reviewed-by: Andrew Jeffery <andrew at aj.id.au>
> Signed-off-by: Joel Stanley <joel at jms.id.au>
Reviewed-by: Benjamin Herrenschmidt <benh at kernel.crashing.org>
> ---
> v7:
> - Rebase on dt-bindings patch
> - Add ASPEED_NUM_CLKS as it no longer lives in the header
> v6:
> - Add SPDX copyright notices
> v5:
> - Add Andrew's reviewed-by
> - Make aspeed_gates not initconst to avoid section mismatch warning
> v3:
> - use named initlisers for aspeed_gates table
> - fix clocks typo
> - Move ASPEED_NUM_CLKS to the bottom of the list
> - Put gates at the start of the list, so we can use them to initalise
> the aspeed_gates table
> - Add ASPEED_CLK_SELECTION_2
> - Set parent of network MAC gates
> ---
> drivers/clk/Kconfig | 12 ++++
> drivers/clk/Makefile | 1 +
> drivers/clk/clk-aspeed.c | 141 +++++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 154 insertions(+)
> create mode 100644 drivers/clk/clk-aspeed.c
>
> diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
> index 1c4e1aa6767e..9abe063ef8d2 100644
> --- a/drivers/clk/Kconfig
> +++ b/drivers/clk/Kconfig
> @@ -142,6 +142,18 @@ config COMMON_CLK_GEMINI
> This driver supports the SoC clocks on the Cortina Systems Gemini
> platform, also known as SL3516 or CS3516.
>
> +config COMMON_CLK_ASPEED
> + bool "Clock driver for Aspeed BMC SoCs"
> + depends on ARCH_ASPEED || COMPILE_TEST
> + default ARCH_ASPEED
> + select MFD_SYSCON
> + select RESET_CONTROLLER
> + ---help---
> + This driver supports the SoC clocks on the Aspeed BMC platforms.
> +
> + The G4 and G5 series, including the ast2400 and ast2500, are supported
> + by this driver.
> +
> config COMMON_CLK_S2MPS11
> tristate "Clock driver for S2MPS1X/S5M8767 MFD"
> depends on MFD_SEC_CORE || COMPILE_TEST
> diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
> index f7f761b02bed..d260da4809f8 100644
> --- a/drivers/clk/Makefile
> +++ b/drivers/clk/Makefile
> @@ -27,6 +27,7 @@ obj-$(CONFIG_ARCH_CLPS711X) += clk-clps711x.o
> obj-$(CONFIG_COMMON_CLK_CS2000_CP) += clk-cs2000-cp.o
> obj-$(CONFIG_ARCH_EFM32) += clk-efm32gg.o
> obj-$(CONFIG_COMMON_CLK_GEMINI) += clk-gemini.o
> +obj-$(CONFIG_COMMON_CLK_ASPEED) += clk-aspeed.o
> obj-$(CONFIG_ARCH_HIGHBANK) += clk-highbank.o
> obj-$(CONFIG_CLK_HSDK) += clk-hsdk-pll.o
> obj-$(CONFIG_COMMON_CLK_MAX77686) += clk-max77686.o
> 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);
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