// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2022, 2023 Linaro Ltd.
*/
#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/interconnect-clk.h>
#include <linux/interconnect-provider.h>
#include <linux/of.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <dt-bindings/interconnect/qcom,msm8996-cbf.h>
#include "clk-alpha-pll.h"
#include "clk-regmap.h"
/* Need to match the order of clocks in DT binding */
enum {
DT_XO,
DT_APCS_AUX,
};
enum {
CBF_XO_INDEX,
CBF_PLL_INDEX,
CBF_DIV_INDEX,
CBF_APCS_AUX_INDEX,
};
#define DIV_THRESHOLD 600000000
#define CBF_MUX_OFFSET 0x18
#define CBF_MUX_PARENT_MASK GENMASK(1, 0)
#define CBF_MUX_AUTO_CLK_SEL_ALWAYS_ON_MASK GENMASK(5, 4)
#define CBF_MUX_AUTO_CLK_SEL_ALWAYS_ON_GPLL0_SEL \
FIELD_PREP(CBF_MUX_AUTO_CLK_SEL_ALWAYS_ON_MASK, 0x03)
#define CBF_MUX_AUTO_CLK_SEL_BIT BIT(6)
#define CBF_PLL_OFFSET 0xf000
static struct alpha_pll_config cbfpll_config = {
.l = 72,
.config_ctl_val = 0x200d4828,
.config_ctl_hi_val = 0x006,
.test_ctl_val = 0x1c000000,
.test_ctl_hi_val = 0x00004000,
.pre_div_mask = BIT(12),
.post_div_mask = 0x3 << 8,
.post_div_val = 0x1 << 8,
.main_output_mask = BIT(0),
.early_output_mask = BIT(3),
};
static struct clk_alpha_pll cbf_pll = {
.offset = CBF_PLL_OFFSET,
.regs = clk_alpha_pll_regs[CLK_ALPHA_PLL_TYPE_HUAYRA_APSS],
.flags = SUPPORTS_DYNAMIC_UPDATE | SUPPORTS_FSM_MODE,
.clkr.hw.init = &(struct clk_init_data){
.name = "cbf_pll",
.parent_data = (const struct clk_parent_data[]) {
{ .index = DT_XO, },
},
.num_parents = 1,
.ops = &clk_alpha_pll_hwfsm_ops,
},
};
static struct clk_fixed_factor cbf_pll_postdiv = {
.mult = 1,
.div = 2,
.hw.init = &(struct clk_init_data){
.name = "cbf_pll_postdiv",
.parent_hws = (const struct clk_hw*[]){
&cbf_pll.clkr.hw
},
.num_parents = 1,
.ops = &clk_fixed_factor_ops,
.flags = CLK_SET_RATE_PARENT,
},
};
static const struct clk_parent_data cbf_mux_parent_data[] = {
{ .index = DT_XO },
{ .hw = &cbf_pll.clkr.hw },
{ .hw = &cbf_pll_postdiv.hw },
{ .index = DT_APCS_AUX },
};
struct clk_cbf_8996_mux {
u32 reg;
struct notifier_block nb;
struct clk_regmap clkr;
};
static struct clk_cbf_8996_mux *to_clk_cbf_8996_mux(struct clk_regmap *clkr)
{
return container_of(clkr, struct clk_cbf_8996_mux, clkr);
}
static int cbf_clk_notifier_cb(struct notifier_block *nb, unsigned long event,
void *data);
static u8 clk_cbf_8996_mux_get_parent(struct clk_hw *hw)
{
struct clk_regmap *clkr = to_clk_regmap(hw);
struct clk_cbf_8996_mux *mux = to_clk_cbf_8996_mux(clkr);
u32 val;
regmap_read(clkr->regmap, mux->reg, &val);
return FIELD_GET(CBF_MUX_PARENT_MASK, val);
}
static int clk_cbf_8996_mux_set_parent(struct clk_hw *hw, u8 index)
{
struct clk_regmap *clkr = to_clk_regmap(hw);
struct clk_cbf_8996_mux *mux = to_clk_cbf_8996_mux(clkr);
u32 val;
val = FIELD_PREP(CBF_MUX_PARENT_MASK, index);
return regmap_update_bits(clkr->regmap, mux->reg, CBF_MUX_PARENT_MASK, val);
}
static int clk_cbf_8996_mux_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
struct clk_hw *parent;
if (req->rate < (DIV_THRESHOLD / cbf_pll_postdiv.div))
return -EINVAL;
if (req->rate < DIV_THRESHOLD)
parent = clk_hw_get_parent_by_index(hw, CBF_DIV_INDEX);
else
parent = clk_hw_get_parent_by_index(hw, CBF_PLL_INDEX);
if (!parent)
return -EINVAL;
req->best_parent_rate = clk_hw_round_rate(parent, req->rate);
req->best_parent_hw = parent;
return 0;
}
static const struct clk_ops clk_cbf_8996_mux_ops = {
.set_parent = clk_cbf_8996_mux_set_parent,
.get_parent = clk_cbf_8996_mux_get_parent,
.determine_rate = clk_cbf_8996_mux_determine_rate,
};
static struct clk_cbf_8996_mux cbf_mux = {
.reg = CBF_MUX_OFFSET,
.nb.notifier_call = cbf_clk_notifier_cb,
.clkr.hw.init = &(struct clk_init_data) {
.name = "cbf_mux",
.parent_data = cbf_mux_parent_data,
.num_parents = ARRAY_SIZE(cbf_mux_parent_data),
.ops = &clk_cbf_8996_mux_ops,
/* CPU clock is critical and should never be gated */
.flags = CLK_SET_RATE_PARENT | CLK_IS_CRITICAL,
},
};
static int cbf_clk_notifier_cb(struct notifier_block *nb, unsigned long event,
void *data)
{
struct clk_notifier_data *cnd = data;
switch (event) {
case PRE_RATE_CHANGE:
/*
* Avoid overvolting. clk_core_set_rate_nolock() walks from top
* to bottom, so it will change the rate of the PLL before
* chaging the parent of PMUX. This can result in pmux getting
* clocked twice the expected rate.
*
* Manually switch to PLL/2 here.
*/
if (cnd->old_rate > DIV_THRESHOLD &&
cnd->new_rate < DIV_THRESHOLD)
clk_cbf_8996_mux_set_parent(&cbf_mux.clkr.hw, CBF_DIV_INDEX);
break;
case ABORT_RATE_CHANGE:
/* Revert manual change */
if (cnd->new_rate < DIV_THRESHOLD &&
cnd->old_rate > DIV_THRESHOLD)
clk_cbf_8996_mux_set_parent(&cbf_mux.clkr.hw, CBF_PLL_INDEX);
break;
default:
break;
}
return notifier_from_errno(0);
};
static struct clk_hw *cbf_msm8996_hw_clks[] = {
&cbf_pll_postdiv.hw,
};
static struct clk_regmap *cbf_msm8996_clks[] = {
&cbf_pll.clkr,
&cbf_mux.clkr,
};
static const struct regmap_config cbf_msm8996_regmap_config = {
.reg_bits = 32,
.reg_stride = 4,
.val_bits = 32,
.max_register = 0x10000,
.fast_io = true,
.val_format_endian = REGMAP_ENDIAN_LITTLE,
};
#ifdef CONFIG_INTERCONNECT
/* Random ID that doesn't clash with main qnoc and OSM */
#define CBF_MASTER_NODE 2000
static int qcom_msm8996_cbf_icc_register(struct platform_device *pdev, struct clk_hw *cbf_hw)
{
struct device *dev = &pdev->dev;
struct clk *clk = devm_clk_hw_get_clk(dev, cbf_hw, "cbf");
const struct icc_clk_data data[] = {
{
.clk = clk,
.name = "cbf",
.master_id = MASTER_CBF_M4M,
.slave_id = SLAVE_CBF_M4M,
},
};
struct icc_provider *provider;
provider = icc_clk_register(dev, CBF_MASTER_NODE, ARRAY_SIZE(data), data);
if (IS_ERR(provider))
return PTR_ERR(provider);
platform_set_drvdata(pdev, provider);
return 0;
}
static void qcom_msm8996_cbf_icc_remove(struct platform_device *pdev)
{
struct icc_provider *provider = platform_get_drvdata(pdev);
icc_clk_unregister(provider);
}
#define qcom_msm8996_cbf_icc_sync_state icc_sync_state
#else
static int qcom_msm8996_cbf_icc_register(struct platform_device *pdev, struct clk_hw *cbf_hw)
{
dev_warn(&pdev->dev, "CONFIG_INTERCONNECT is disabled, CBF clock is fixed\n");
return 0;
}
#define qcom_msm8996_cbf_icc_remove(pdev) { }
#define qcom_msm8996_cbf_icc_sync_state NULL
#endif
static int qcom_msm8996_cbf_probe(struct platform_device *pdev)
{
void __iomem *base;
struct regmap *regmap;
struct device *dev = &pdev->dev;
int i, ret;
base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(base))
return PTR_ERR(base);
regmap = devm_regmap_init_mmio(dev, base, &cbf_msm8996_regmap_config);
if (IS_ERR(regmap))
return PTR_ERR(regmap);
/* Select GPLL0 for 300MHz for the CBF clock */
regmap_write(regmap, CBF_MUX_OFFSET, 0x3);
/* Ensure write goes through before PLLs are reconfigured */
udelay(5);
/* Set the auto clock sel always-on source to GPLL0/2 (300MHz) */
regmap_update_bits(regmap, CBF_MUX_OFFSET,
CBF_MUX_AUTO_CLK_SEL_ALWAYS_ON_MASK,
CBF_MUX_AUTO_CLK_SEL_ALWAYS_ON_GPLL0_SEL);
clk_alpha_pll_configure(&cbf_pll, regmap, &cbfpll_config);
/* Wait for PLL(s) to lock */
udelay(50);
/* Enable auto clock selection for CBF */
regmap_update_bits(regmap, CBF_MUX_OFFSET,
CBF_MUX_AUTO_CLK_SEL_BIT,
CBF_MUX_AUTO_CLK_SEL_BIT);
/* Ensure write goes through before muxes are switched */
udelay(5);
/* Switch CBF to use the primary PLL */
regmap_update_bits(regmap, CBF_MUX_OFFSET, CBF_MUX_PARENT_MASK, 0x1);
if (of_device_is_compatible(dev->of_node, "qcom,msm8996pro-cbf")) {
cbfpll_config.post_div_val = 0x3 << 8;
cbf_pll_postdiv.div = 4;
}
for (i = 0; i < ARRAY_SIZE(cbf_msm8996_hw_clks); i++) {
ret = devm_clk_hw_register(dev, cbf_msm8996_hw_clks[i]);
if (ret)
return ret;
}
for (i = 0; i < ARRAY_SIZE(cbf_msm8996_clks); i++) {
ret = devm_clk_register_regmap(dev, cbf_msm8996_clks[i]);
if (ret)
return ret;
}
ret = devm_clk_notifier_register(dev, cbf_mux.clkr.hw.clk, &cbf_mux.nb);
if (ret)
return ret;
ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get, &cbf_mux.clkr.hw);
if (ret)
return ret;
return qcom_msm8996_cbf_icc_register(pdev, &cbf_mux.clkr.hw);
}
static void qcom_msm8996_cbf_remove(struct platform_device *pdev)
{
qcom_msm8996_cbf_icc_remove(pdev);
}
static const struct of_device_id qcom_msm8996_cbf_match_table[] = {
{ .compatible = "qcom,msm8996-cbf" },
{ .compatible = "qcom,msm8996pro-cbf" },
{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, qcom_msm8996_cbf_match_table);
static struct platform_driver qcom_msm8996_cbf_driver = {
.probe = qcom_msm8996_cbf_probe,
.remove = qcom_msm8996_cbf_remove,
.driver = {
.name = "qcom-msm8996-cbf",
.of_match_table = qcom_msm8996_cbf_match_table,
.sync_state = qcom_msm8996_cbf_icc_sync_state,
},
};
/* Register early enough to fix the clock to be used for other cores */
static int __init qcom_msm8996_cbf_init(void)
{
return platform_driver_register(&qcom_msm8996_cbf_driver);
}
postcore_initcall(qcom_msm8996_cbf_init);
static void __exit qcom_msm8996_cbf_exit(void)
{
platform_driver_unregister(&qcom_msm8996_cbf_driver);
}
module_exit(qcom_msm8996_cbf_exit);
MODULE_DESCRIPTION("QCOM MSM8996 CPU Bus Fabric Clock Driver");
MODULE_LICENSE("GPL");
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