diff options
Diffstat (limited to 'drivers/clk')
-rw-r--r-- | drivers/clk/imx/Kconfig | 4 | ||||
-rw-r--r-- | drivers/clk/imx/Makefile | 3 | ||||
-rw-r--r-- | drivers/clk/imx/clk-scu.c | 270 | ||||
-rw-r--r-- | drivers/clk/imx/clk-scu.h | 15 |
4 files changed, 292 insertions, 0 deletions
diff --git a/drivers/clk/imx/Kconfig b/drivers/clk/imx/Kconfig index bdd85b89687b..2a3b58d7bddf 100644 --- a/drivers/clk/imx/Kconfig +++ b/drivers/clk/imx/Kconfig @@ -3,3 +3,7 @@ config MXC_CLK bool def_bool ARCH_MXC + +config MXC_CLK_SCU + bool + depends on IMX_SCU diff --git a/drivers/clk/imx/Makefile b/drivers/clk/imx/Makefile index d447f8c0500b..eec6d72ea5fb 100644 --- a/drivers/clk/imx/Makefile +++ b/drivers/clk/imx/Makefile @@ -13,6 +13,9 @@ obj-$(CONFIG_MXC_CLK) += \ clk-pllv3.o \ clk-pfd.o +obj-$(CONFIG_MXC_CLK_SCU) += \ + clk-scu.o + obj-$(CONFIG_SOC_IMX1) += clk-imx1.o obj-$(CONFIG_SOC_IMX21) += clk-imx21.o obj-$(CONFIG_SOC_IMX25) += clk-imx25.o diff --git a/drivers/clk/imx/clk-scu.c b/drivers/clk/imx/clk-scu.c new file mode 100644 index 000000000000..7ccf7edfe11c --- /dev/null +++ b/drivers/clk/imx/clk-scu.c @@ -0,0 +1,270 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2018 NXP + * Dong Aisheng <aisheng.dong@nxp.com> + */ + +#include <linux/clk-provider.h> +#include <linux/err.h> +#include <linux/slab.h> + +#include "clk-scu.h" + +static struct imx_sc_ipc *ccm_ipc_handle; + +/* + * struct clk_scu - Description of one SCU clock + * @hw: the common clk_hw + * @rsrc_id: resource ID of this SCU clock + * @clk_type: type of this clock resource + */ +struct clk_scu { + struct clk_hw hw; + u16 rsrc_id; + u8 clk_type; +}; + +/* + * struct imx_sc_msg_req_set_clock_rate - clock set rate protocol + * @hdr: SCU protocol header + * @rate: rate to set + * @resource: clock resource to set rate + * @clk: clk type of this resource + * + * This structure describes the SCU protocol of clock rate set + */ +struct imx_sc_msg_req_set_clock_rate { + struct imx_sc_rpc_msg hdr; + __le32 rate; + __le16 resource; + u8 clk; +} __packed; + +struct req_get_clock_rate { + __le16 resource; + u8 clk; +} __packed; + +struct resp_get_clock_rate { + __le32 rate; +}; + +/* + * struct imx_sc_msg_get_clock_rate - clock get rate protocol + * @hdr: SCU protocol header + * @req: get rate request protocol + * @resp: get rate response protocol + * + * This structure describes the SCU protocol of clock rate get + */ +struct imx_sc_msg_get_clock_rate { + struct imx_sc_rpc_msg hdr; + union { + struct req_get_clock_rate req; + struct resp_get_clock_rate resp; + } data; +}; + +/* + * struct imx_sc_msg_req_clock_enable - clock gate protocol + * @hdr: SCU protocol header + * @resource: clock resource to gate + * @clk: clk type of this resource + * @enable: whether gate off the clock + * @autog: HW auto gate enable + * + * This structure describes the SCU protocol of clock gate + */ +struct imx_sc_msg_req_clock_enable { + struct imx_sc_rpc_msg hdr; + __le16 resource; + u8 clk; + u8 enable; + u8 autog; +} __packed; + +static inline struct clk_scu *to_clk_scu(struct clk_hw *hw) +{ + return container_of(hw, struct clk_scu, hw); +} + +int imx_clk_scu_init(void) +{ + return imx_scu_get_handle(&ccm_ipc_handle); +} + +/* + * clk_scu_recalc_rate - Get clock rate for a SCU clock + * @hw: clock to get rate for + * @parent_rate: parent rate provided by common clock framework, not used + * + * Gets the current clock rate of a SCU clock. Returns the current + * clock rate, or zero in failure. + */ +static unsigned long clk_scu_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_scu *clk = to_clk_scu(hw); + struct imx_sc_msg_get_clock_rate msg; + struct imx_sc_rpc_msg *hdr = &msg.hdr; + int ret; + + hdr->ver = IMX_SC_RPC_VERSION; + hdr->svc = IMX_SC_RPC_SVC_PM; + hdr->func = IMX_SC_PM_FUNC_GET_CLOCK_RATE; + hdr->size = 2; + + msg.data.req.resource = cpu_to_le16(clk->rsrc_id); + msg.data.req.clk = clk->clk_type; + + ret = imx_scu_call_rpc(ccm_ipc_handle, &msg, true); + if (ret) { + pr_err("%s: failed to get clock rate %d\n", + clk_hw_get_name(hw), ret); + return 0; + } + + return le32_to_cpu(msg.data.resp.rate); +} + +/* + * clk_scu_round_rate - Round clock rate for a SCU clock + * @hw: clock to round rate for + * @rate: rate to round + * @parent_rate: parent rate provided by common clock framework, not used + * + * Returns the current clock rate, or zero in failure. + */ +static long clk_scu_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + /* + * Assume we support all the requested rate and let the SCU firmware + * to handle the left work + */ + return rate; +} + +/* + * clk_scu_set_rate - Set rate for a SCU clock + * @hw: clock to change rate for + * @rate: target rate for the clock + * @parent_rate: rate of the clock parent, not used for SCU clocks + * + * Sets a clock frequency for a SCU clock. Returns the SCU + * protocol status. + */ +static int clk_scu_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_scu *clk = to_clk_scu(hw); + struct imx_sc_msg_req_set_clock_rate msg; + struct imx_sc_rpc_msg *hdr = &msg.hdr; + + hdr->ver = IMX_SC_RPC_VERSION; + hdr->svc = IMX_SC_RPC_SVC_PM; + hdr->func = IMX_SC_PM_FUNC_SET_CLOCK_RATE; + hdr->size = 3; + + msg.rate = cpu_to_le32(rate); + msg.resource = cpu_to_le16(clk->rsrc_id); + msg.clk = clk->clk_type; + + return imx_scu_call_rpc(ccm_ipc_handle, &msg, true); +} + +static int sc_pm_clock_enable(struct imx_sc_ipc *ipc, u16 resource, + u8 clk, bool enable, bool autog) +{ + struct imx_sc_msg_req_clock_enable msg; + struct imx_sc_rpc_msg *hdr = &msg.hdr; + + hdr->ver = IMX_SC_RPC_VERSION; + hdr->svc = IMX_SC_RPC_SVC_PM; + hdr->func = IMX_SC_PM_FUNC_CLOCK_ENABLE; + hdr->size = 3; + + msg.resource = cpu_to_le16(resource); + msg.clk = clk; + msg.enable = enable; + msg.autog = autog; + + return imx_scu_call_rpc(ccm_ipc_handle, &msg, true); +} + +/* + * clk_scu_prepare - Enable a SCU clock + * @hw: clock to enable + * + * Enable the clock at the DSC slice level + */ +static int clk_scu_prepare(struct clk_hw *hw) +{ + struct clk_scu *clk = to_clk_scu(hw); + + return sc_pm_clock_enable(ccm_ipc_handle, clk->rsrc_id, + clk->clk_type, true, false); +} + +/* + * clk_scu_unprepare - Disable a SCU clock + * @hw: clock to enable + * + * Disable the clock at the DSC slice level + */ +static void clk_scu_unprepare(struct clk_hw *hw) +{ + struct clk_scu *clk = to_clk_scu(hw); + int ret; + + ret = sc_pm_clock_enable(ccm_ipc_handle, clk->rsrc_id, + clk->clk_type, false, false); + if (ret) + pr_warn("%s: clk unprepare failed %d\n", clk_hw_get_name(hw), + ret); +} + +static const struct clk_ops clk_scu_ops = { + .recalc_rate = clk_scu_recalc_rate, + .round_rate = clk_scu_round_rate, + .set_rate = clk_scu_set_rate, + .prepare = clk_scu_prepare, + .unprepare = clk_scu_unprepare, +}; + +struct clk_hw *imx_clk_scu(const char *name, u32 rsrc_id, u8 clk_type) +{ + struct clk_init_data init; + struct clk_scu *clk; + struct clk_hw *hw; + int ret; + + clk = kzalloc(sizeof(*clk), GFP_KERNEL); + if (!clk) + return ERR_PTR(-ENOMEM); + + clk->rsrc_id = rsrc_id; + clk->clk_type = clk_type; + + init.name = name; + init.ops = &clk_scu_ops; + init.num_parents = 0; + /* + * Note on MX8, the clocks are tightly coupled with power domain + * that once the power domain is off, the clock status may be + * lost. So we make it NOCACHE to let user to retrieve the real + * clock status from HW instead of using the possible invalid + * cached rate. + */ + init.flags = CLK_GET_RATE_NOCACHE; + clk->hw.init = &init; + + hw = &clk->hw; + ret = clk_hw_register(NULL, hw); + if (ret) { + kfree(clk); + hw = ERR_PTR(ret); + } + + return hw; +} diff --git a/drivers/clk/imx/clk-scu.h b/drivers/clk/imx/clk-scu.h new file mode 100644 index 000000000000..309b4de20b25 --- /dev/null +++ b/drivers/clk/imx/clk-scu.h @@ -0,0 +1,15 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Copyright 2018 NXP + * Dong Aisheng <aisheng.dong@nxp.com> + */ + +#ifndef __IMX_CLK_SCU_H +#define __IMX_CLK_SCU_H + +#include <linux/firmware/imx/sci.h> + +int imx_clk_scu_init(void); +struct clk_hw *imx_clk_scu(const char *name, u32 rsrc_id, u8 clk_type); + +#endif |