linux/drivers/clk/imx/clk-scu.c
Dong Aisheng 5392c5de09 clk: imx: scu: add gpr clocks support
SCU clock protocol supports a few clocks based on GPR controller
registers including mux/divider/gate.
Add a generic clock register API to support them all.

Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Reviewed-by: Abel Vesa <abel.vesa@nxp.com>
Signed-off-by: Abel Vesa <abel.vesa@nxp.com>
2021-06-14 12:33:17 +03:00

794 lines
18 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright 2018 NXP
* Dong Aisheng <aisheng.dong@nxp.com>
*/
#include <dt-bindings/firmware/imx/rsrc.h>
#include <linux/arm-smccc.h>
#include <linux/clk-provider.h>
#include <linux/err.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/pm_domain.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include "clk-scu.h"
#define IMX_SIP_CPUFREQ 0xC2000001
#define IMX_SIP_SET_CPUFREQ 0x00
static struct imx_sc_ipc *ccm_ipc_handle;
static struct device_node *pd_np;
static struct platform_driver imx_clk_scu_driver;
struct imx_scu_clk_node {
const char *name;
u32 rsrc;
u8 clk_type;
const char * const *parents;
int num_parents;
struct clk_hw *hw;
struct list_head node;
};
struct list_head imx_scu_clks[IMX_SC_R_LAST];
/*
* 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;
/* for state save&restore */
bool is_enabled;
u32 rate;
};
/*
* struct clk_gpr_scu - Description of one SCU GPR clock
* @hw: the common clk_hw
* @rsrc_id: resource ID of this SCU clock
* @gpr_id: GPR ID index to control the divider
*/
struct clk_gpr_scu {
struct clk_hw hw;
u16 rsrc_id;
u8 gpr_id;
u8 flags;
bool gate_invert;
};
#define to_clk_gpr_scu(_hw) container_of(_hw, struct clk_gpr_scu, hw)
/*
* 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 __aligned(4);
struct req_get_clock_rate {
__le16 resource;
u8 clk;
} __packed __aligned(4);
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_get_clock_parent - clock get parent protocol
* @hdr: SCU protocol header
* @req: get parent request protocol
* @resp: get parent response protocol
*
* This structure describes the SCU protocol of clock get parent
*/
struct imx_sc_msg_get_clock_parent {
struct imx_sc_rpc_msg hdr;
union {
struct req_get_clock_parent {
__le16 resource;
u8 clk;
} __packed __aligned(4) req;
struct resp_get_clock_parent {
u8 parent;
} resp;
} data;
};
/*
* struct imx_sc_msg_set_clock_parent - clock set parent protocol
* @hdr: SCU protocol header
* @req: set parent request protocol
*
* This structure describes the SCU protocol of clock set parent
*/
struct imx_sc_msg_set_clock_parent {
struct imx_sc_rpc_msg hdr;
__le16 resource;
u8 clk;
u8 parent;
} __packed;
/*
* 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 __aligned(4);
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(struct device_node *np)
{
u32 clk_cells;
int ret, i;
ret = imx_scu_get_handle(&ccm_ipc_handle);
if (ret)
return ret;
of_property_read_u32(np, "#clock-cells", &clk_cells);
if (clk_cells == 2) {
for (i = 0; i < IMX_SC_R_LAST; i++)
INIT_LIST_HEAD(&imx_scu_clks[i]);
/* pd_np will be used to attach power domains later */
pd_np = of_find_compatible_node(NULL, NULL, "fsl,scu-pd");
if (!pd_np)
return -EINVAL;
}
return platform_driver_register(&imx_clk_scu_driver);
}
/*
* 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;
}
static int clk_scu_atf_set_cpu_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct clk_scu *clk = to_clk_scu(hw);
struct arm_smccc_res res;
unsigned long cluster_id;
if (clk->rsrc_id == IMX_SC_R_A35)
cluster_id = 0;
else
return -EINVAL;
/* CPU frequency scaling can ONLY be done by ARM-Trusted-Firmware */
arm_smccc_smc(IMX_SIP_CPUFREQ, IMX_SIP_SET_CPUFREQ,
cluster_id, rate, 0, 0, 0, 0, &res);
return 0;
}
/*
* 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 u8 clk_scu_get_parent(struct clk_hw *hw)
{
struct clk_scu *clk = to_clk_scu(hw);
struct imx_sc_msg_get_clock_parent 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_PARENT;
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 parent %d\n",
clk_hw_get_name(hw), ret);
return 0;
}
return msg.data.resp.parent;
}
static int clk_scu_set_parent(struct clk_hw *hw, u8 index)
{
struct clk_scu *clk = to_clk_scu(hw);
struct imx_sc_msg_set_clock_parent 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_PARENT;
hdr->size = 2;
msg.resource = cpu_to_le16(clk->rsrc_id);
msg.clk = clk->clk_type;
msg.parent = index;
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,
.get_parent = clk_scu_get_parent,
.set_parent = clk_scu_set_parent,
.prepare = clk_scu_prepare,
.unprepare = clk_scu_unprepare,
};
static const struct clk_ops clk_scu_cpu_ops = {
.recalc_rate = clk_scu_recalc_rate,
.round_rate = clk_scu_round_rate,
.set_rate = clk_scu_atf_set_cpu_rate,
.prepare = clk_scu_prepare,
.unprepare = clk_scu_unprepare,
};
struct clk_hw *__imx_clk_scu(struct device *dev, const char *name,
const char * const *parents, int num_parents,
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;
if (rsrc_id == IMX_SC_R_A35)
init.ops = &clk_scu_cpu_ops;
else
init.ops = &clk_scu_ops;
init.parent_names = parents;
init.num_parents = num_parents;
/*
* 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(dev, hw);
if (ret) {
kfree(clk);
hw = ERR_PTR(ret);
return hw;
}
if (dev)
dev_set_drvdata(dev, clk);
return hw;
}
struct clk_hw *imx_scu_of_clk_src_get(struct of_phandle_args *clkspec,
void *data)
{
unsigned int rsrc = clkspec->args[0];
unsigned int idx = clkspec->args[1];
struct list_head *scu_clks = data;
struct imx_scu_clk_node *clk;
list_for_each_entry(clk, &scu_clks[rsrc], node) {
if (clk->clk_type == idx)
return clk->hw;
}
return ERR_PTR(-ENODEV);
}
static int imx_clk_scu_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct imx_scu_clk_node *clk = dev_get_platdata(dev);
struct clk_hw *hw;
int ret;
pm_runtime_set_suspended(dev);
pm_runtime_set_autosuspend_delay(dev, 50);
pm_runtime_use_autosuspend(&pdev->dev);
pm_runtime_enable(dev);
ret = pm_runtime_get_sync(dev);
if (ret) {
pm_runtime_disable(dev);
return ret;
}
hw = __imx_clk_scu(dev, clk->name, clk->parents, clk->num_parents,
clk->rsrc, clk->clk_type);
if (IS_ERR(hw)) {
pm_runtime_disable(dev);
return PTR_ERR(hw);
}
clk->hw = hw;
list_add_tail(&clk->node, &imx_scu_clks[clk->rsrc]);
pm_runtime_mark_last_busy(&pdev->dev);
pm_runtime_put_autosuspend(&pdev->dev);
dev_dbg(dev, "register SCU clock rsrc:%d type:%d\n", clk->rsrc,
clk->clk_type);
return 0;
}
static int __maybe_unused imx_clk_scu_suspend(struct device *dev)
{
struct clk_scu *clk = dev_get_drvdata(dev);
clk->rate = clk_hw_get_rate(&clk->hw);
clk->is_enabled = clk_hw_is_enabled(&clk->hw);
if (clk->rate)
dev_dbg(dev, "save rate %d\n", clk->rate);
if (clk->is_enabled)
dev_dbg(dev, "save enabled state\n");
return 0;
}
static int __maybe_unused imx_clk_scu_resume(struct device *dev)
{
struct clk_scu *clk = dev_get_drvdata(dev);
int ret = 0;
if (clk->rate) {
ret = clk_scu_set_rate(&clk->hw, clk->rate, 0);
dev_dbg(dev, "restore rate %d %s\n", clk->rate,
!ret ? "success" : "failed");
}
if (clk->is_enabled) {
ret = clk_scu_prepare(&clk->hw);
dev_dbg(dev, "restore enabled state %s\n",
!ret ? "success" : "failed");
}
return ret;
}
static const struct dev_pm_ops imx_clk_scu_pm_ops = {
SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx_clk_scu_suspend,
imx_clk_scu_resume)
};
static struct platform_driver imx_clk_scu_driver = {
.driver = {
.name = "imx-scu-clk",
.suppress_bind_attrs = true,
.pm = &imx_clk_scu_pm_ops,
},
.probe = imx_clk_scu_probe,
};
static int imx_clk_scu_attach_pd(struct device *dev, u32 rsrc_id)
{
struct of_phandle_args genpdspec = {
.np = pd_np,
.args_count = 1,
.args[0] = rsrc_id,
};
if (rsrc_id == IMX_SC_R_A35 || rsrc_id == IMX_SC_R_A53 ||
rsrc_id == IMX_SC_R_A72)
return 0;
return of_genpd_add_device(&genpdspec, dev);
}
struct clk_hw *imx_clk_scu_alloc_dev(const char *name,
const char * const *parents,
int num_parents, u32 rsrc_id, u8 clk_type)
{
struct imx_scu_clk_node clk = {
.name = name,
.rsrc = rsrc_id,
.clk_type = clk_type,
.parents = parents,
.num_parents = num_parents,
};
struct platform_device *pdev;
int ret;
pdev = platform_device_alloc(name, PLATFORM_DEVID_NONE);
if (!pdev) {
pr_err("%s: failed to allocate scu clk dev rsrc %d type %d\n",
name, rsrc_id, clk_type);
return ERR_PTR(-ENOMEM);
}
ret = platform_device_add_data(pdev, &clk, sizeof(clk));
if (ret) {
platform_device_put(pdev);
return ERR_PTR(ret);
}
pdev->driver_override = "imx-scu-clk";
ret = imx_clk_scu_attach_pd(&pdev->dev, rsrc_id);
if (ret)
pr_warn("%s: failed to attached the power domain %d\n",
name, ret);
platform_device_add(pdev);
/* For API backwards compatiblilty, simply return NULL for success */
return NULL;
}
void imx_clk_scu_unregister(void)
{
struct imx_scu_clk_node *clk;
int i;
for (i = 0; i < IMX_SC_R_LAST; i++) {
list_for_each_entry(clk, &imx_scu_clks[i], node) {
clk_hw_unregister(clk->hw);
kfree(clk);
}
}
}
static unsigned long clk_gpr_div_scu_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
unsigned long rate = 0;
u32 val;
int err;
err = imx_sc_misc_get_control(ccm_ipc_handle, clk->rsrc_id,
clk->gpr_id, &val);
rate = val ? parent_rate / 2 : parent_rate;
return err ? 0 : rate;
}
static long clk_gpr_div_scu_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *prate)
{
if (rate < *prate)
rate = *prate / 2;
else
rate = *prate;
return rate;
}
static int clk_gpr_div_scu_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
uint32_t val;
int err;
val = (rate < parent_rate) ? 1 : 0;
err = imx_sc_misc_set_control(ccm_ipc_handle, clk->rsrc_id,
clk->gpr_id, val);
return err ? -EINVAL : 0;
}
static const struct clk_ops clk_gpr_div_scu_ops = {
.recalc_rate = clk_gpr_div_scu_recalc_rate,
.round_rate = clk_gpr_div_scu_round_rate,
.set_rate = clk_gpr_div_scu_set_rate,
};
static u8 clk_gpr_mux_scu_get_parent(struct clk_hw *hw)
{
struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
u32 val = 0;
imx_sc_misc_get_control(ccm_ipc_handle, clk->rsrc_id,
clk->gpr_id, &val);
return (u8)val;
}
static int clk_gpr_mux_scu_set_parent(struct clk_hw *hw, u8 index)
{
struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
return imx_sc_misc_set_control(ccm_ipc_handle, clk->rsrc_id,
clk->gpr_id, index);
}
static const struct clk_ops clk_gpr_mux_scu_ops = {
.get_parent = clk_gpr_mux_scu_get_parent,
.set_parent = clk_gpr_mux_scu_set_parent,
};
static int clk_gpr_gate_scu_prepare(struct clk_hw *hw)
{
struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
return imx_sc_misc_set_control(ccm_ipc_handle, clk->rsrc_id,
clk->gpr_id, !clk->gate_invert);
}
static void clk_gpr_gate_scu_unprepare(struct clk_hw *hw)
{
struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
int ret;
ret = imx_sc_misc_set_control(ccm_ipc_handle, clk->rsrc_id,
clk->gpr_id, clk->gate_invert);
if (ret)
pr_err("%s: clk unprepare failed %d\n", clk_hw_get_name(hw),
ret);
}
static int clk_gpr_gate_scu_is_prepared(struct clk_hw *hw)
{
struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
int ret;
u32 val;
ret = imx_sc_misc_get_control(ccm_ipc_handle, clk->rsrc_id,
clk->gpr_id, &val);
if (ret)
return ret;
return clk->gate_invert ? !val : val;
}
static const struct clk_ops clk_gpr_gate_scu_ops = {
.prepare = clk_gpr_gate_scu_prepare,
.unprepare = clk_gpr_gate_scu_unprepare,
.is_prepared = clk_gpr_gate_scu_is_prepared,
};
struct clk_hw *__imx_clk_gpr_scu(const char *name, const char * const *parent_name,
int num_parents, u32 rsrc_id, u8 gpr_id, u8 flags,
bool invert)
{
struct imx_scu_clk_node *clk_node;
struct clk_gpr_scu *clk;
struct clk_hw *hw;
struct clk_init_data init;
int ret;
if (rsrc_id >= IMX_SC_R_LAST || gpr_id >= IMX_SC_C_LAST)
return ERR_PTR(-EINVAL);
clk_node = kzalloc(sizeof(*clk_node), GFP_KERNEL);
if (!clk_node)
return ERR_PTR(-ENOMEM);
clk = kzalloc(sizeof(*clk), GFP_KERNEL);
if (!clk) {
kfree(clk_node);
return ERR_PTR(-ENOMEM);
}
clk->rsrc_id = rsrc_id;
clk->gpr_id = gpr_id;
clk->flags = flags;
clk->gate_invert = invert;
if (flags & IMX_SCU_GPR_CLK_GATE)
init.ops = &clk_gpr_gate_scu_ops;
if (flags & IMX_SCU_GPR_CLK_DIV)
init.ops = &clk_gpr_div_scu_ops;
if (flags & IMX_SCU_GPR_CLK_MUX)
init.ops = &clk_gpr_mux_scu_ops;
init.flags = 0;
init.name = name;
init.parent_names = parent_name;
init.num_parents = num_parents;
clk->hw.init = &init;
hw = &clk->hw;
ret = clk_hw_register(NULL, hw);
if (ret) {
kfree(clk);
kfree(clk_node);
hw = ERR_PTR(ret);
} else {
clk_node->hw = hw;
clk_node->clk_type = gpr_id;
list_add_tail(&clk_node->node, &imx_scu_clks[rsrc_id]);
}
return hw;
}