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// SPDX-License-Identifier: GPL-2.0-only
/*
* Daire McNamara,<daire.mcnamara@microchip.com>
* Copyright (C) 2020 Microchip Technology Inc. All rights reserved.
*/
#include <linux/auxiliary_bus.h>
#include <linux/clk-provider.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <dt-bindings/clock/microchip,mpfs-clock.h>
#include <soc/microchip/mpfs.h>
/* address offset of control registers */
#define REG_MSSPLL_REF_CR 0x08u
#define REG_MSSPLL_POSTDIV_CR 0x10u
#define REG_MSSPLL_SSCG_2_CR 0x2Cu
#define REG_CLOCK_CONFIG_CR 0x08u
#define REG_RTC_CLOCK_CR 0x0Cu
#define REG_SUBBLK_CLOCK_CR 0x84u
#define REG_SUBBLK_RESET_CR 0x88u
#define MSSPLL_FBDIV_SHIFT 0x00u
#define MSSPLL_FBDIV_WIDTH 0x0Cu
#define MSSPLL_REFDIV_SHIFT 0x08u
#define MSSPLL_REFDIV_WIDTH 0x06u
#define MSSPLL_POSTDIV_SHIFT 0x08u
#define MSSPLL_POSTDIV_WIDTH 0x07u
#define MSSPLL_FIXED_DIV 4u
struct mpfs_clock_data {
struct device *dev;
void __iomem *base;
void __iomem *msspll_base;
struct clk_hw_onecell_data hw_data;
};
struct mpfs_msspll_hw_clock {
void __iomem *base;
unsigned int id;
u32 reg_offset;
u32 shift;
u32 width;
u32 flags;
struct clk_hw hw;
struct clk_init_data init;
};
#define to_mpfs_msspll_clk(_hw) container_of(_hw, struct mpfs_msspll_hw_clock, hw)
struct mpfs_cfg_hw_clock {
struct clk_divider cfg;
struct clk_init_data init;
unsigned int id;
u32 reg_offset;
};
struct mpfs_periph_hw_clock {
struct clk_gate periph;
unsigned int id;
};
/*
* mpfs_clk_lock prevents anything else from writing to the
* mpfs clk block while a software locked register is being written.
*/
static DEFINE_SPINLOCK(mpfs_clk_lock);
static const struct clk_parent_data mpfs_ext_ref[] = {
{ .index = 0 },
};
static const struct clk_div_table mpfs_div_cpu_axi_table[] = {
{ 0, 1 }, { 1, 2 }, { 2, 4 }, { 3, 8 },
{ 0, 0 }
};
static const struct clk_div_table mpfs_div_ahb_table[] = {
{ 1, 2 }, { 2, 4}, { 3, 8 },
{ 0, 0 }
};
/*
* The only two supported reference clock frequencies for the PolarFire SoC are
* 100 and 125 MHz, as the rtc reference is required to be 1 MHz.
* It therefore only needs to have divider table entries corresponding to
* divide by 100 and 125.
*/
static const struct clk_div_table mpfs_div_rtcref_table[] = {
{ 100, 100 }, { 125, 125 },
{ 0, 0 }
};
static unsigned long mpfs_clk_msspll_recalc_rate(struct clk_hw *hw, unsigned long prate)
{
struct mpfs_msspll_hw_clock *msspll_hw = to_mpfs_msspll_clk(hw);
void __iomem *mult_addr = msspll_hw->base + msspll_hw->reg_offset;
void __iomem *ref_div_addr = msspll_hw->base + REG_MSSPLL_REF_CR;
void __iomem *postdiv_addr = msspll_hw->base + REG_MSSPLL_POSTDIV_CR;
u32 mult, ref_div, postdiv;
mult = readl_relaxed(mult_addr) >> MSSPLL_FBDIV_SHIFT;
mult &= clk_div_mask(MSSPLL_FBDIV_WIDTH);
ref_div = readl_relaxed(ref_div_addr) >> MSSPLL_REFDIV_SHIFT;
ref_div &= clk_div_mask(MSSPLL_REFDIV_WIDTH);
postdiv = readl_relaxed(postdiv_addr) >> MSSPLL_POSTDIV_SHIFT;
postdiv &= clk_div_mask(MSSPLL_POSTDIV_WIDTH);
return prate * mult / (ref_div * MSSPLL_FIXED_DIV * postdiv);
}
static long mpfs_clk_msspll_round_rate(struct clk_hw *hw, unsigned long rate, unsigned long *prate)
{
struct mpfs_msspll_hw_clock *msspll_hw = to_mpfs_msspll_clk(hw);
void __iomem *mult_addr = msspll_hw->base + msspll_hw->reg_offset;
void __iomem *ref_div_addr = msspll_hw->base + REG_MSSPLL_REF_CR;
u32 mult, ref_div;
unsigned long rate_before_ctrl;
mult = readl_relaxed(mult_addr) >> MSSPLL_FBDIV_SHIFT;
mult &= clk_div_mask(MSSPLL_FBDIV_WIDTH);
ref_div = readl_relaxed(ref_div_addr) >> MSSPLL_REFDIV_SHIFT;
ref_div &= clk_div_mask(MSSPLL_REFDIV_WIDTH);
rate_before_ctrl = rate * (ref_div * MSSPLL_FIXED_DIV) / mult;
return divider_round_rate(hw, rate_before_ctrl, prate, NULL, MSSPLL_POSTDIV_WIDTH,
msspll_hw->flags);
}
static int mpfs_clk_msspll_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long prate)
{
struct mpfs_msspll_hw_clock *msspll_hw = to_mpfs_msspll_clk(hw);
void __iomem *mult_addr = msspll_hw->base + msspll_hw->reg_offset;
void __iomem *ref_div_addr = msspll_hw->base + REG_MSSPLL_REF_CR;
void __iomem *postdiv_addr = msspll_hw->base + REG_MSSPLL_POSTDIV_CR;
u32 mult, ref_div, postdiv;
int divider_setting;
unsigned long rate_before_ctrl, flags;
mult = readl_relaxed(mult_addr) >> MSSPLL_FBDIV_SHIFT;
mult &= clk_div_mask(MSSPLL_FBDIV_WIDTH);
ref_div = readl_relaxed(ref_div_addr) >> MSSPLL_REFDIV_SHIFT;
ref_div &= clk_div_mask(MSSPLL_REFDIV_WIDTH);
rate_before_ctrl = rate * (ref_div * MSSPLL_FIXED_DIV) / mult;
divider_setting = divider_get_val(rate_before_ctrl, prate, NULL, MSSPLL_POSTDIV_WIDTH,
msspll_hw->flags);
if (divider_setting < 0)
return divider_setting;
spin_lock_irqsave(&mpfs_clk_lock, flags);
postdiv = readl_relaxed(postdiv_addr);
postdiv &= ~(clk_div_mask(MSSPLL_POSTDIV_WIDTH) << MSSPLL_POSTDIV_SHIFT);
writel_relaxed(postdiv, postdiv_addr);
spin_unlock_irqrestore(&mpfs_clk_lock, flags);
return 0;
}
static const struct clk_ops mpfs_clk_msspll_ops = {
.recalc_rate = mpfs_clk_msspll_recalc_rate,
.round_rate = mpfs_clk_msspll_round_rate,
.set_rate = mpfs_clk_msspll_set_rate,
};
#define CLK_PLL(_id, _name, _parent, _shift, _width, _flags, _offset) { \
.id = _id, \
.shift = _shift, \
.width = _width, \
.reg_offset = _offset, \
.flags = _flags, \
.hw.init = CLK_HW_INIT_PARENTS_DATA(_name, _parent, &mpfs_clk_msspll_ops, 0), \
}
static struct mpfs_msspll_hw_clock mpfs_msspll_clks[] = {
CLK_PLL(CLK_MSSPLL, "clk_msspll", mpfs_ext_ref, MSSPLL_FBDIV_SHIFT,
MSSPLL_FBDIV_WIDTH, 0, REG_MSSPLL_SSCG_2_CR),
};
static int mpfs_clk_register_mssplls(struct device *dev, struct mpfs_msspll_hw_clock *msspll_hws,
unsigned int num_clks, struct mpfs_clock_data *data)
{
unsigned int i;
int ret;
for (i = 0; i < num_clks; i++) {
struct mpfs_msspll_hw_clock *msspll_hw = &msspll_hws[i];
msspll_hw->base = data->msspll_base;
ret = devm_clk_hw_register(dev, &msspll_hw->hw);
if (ret)
return dev_err_probe(dev, ret, "failed to register msspll id: %d\n",
CLK_MSSPLL);
data->hw_data.hws[msspll_hw->id] = &msspll_hw->hw;
}
return 0;
}
/*
* "CFG" clocks
*/
#define CLK_CFG(_id, _name, _parent, _shift, _width, _table, _flags, _offset) { \
.id = _id, \
.cfg.shift = _shift, \
.cfg.width = _width, \
.cfg.table = _table, \
.reg_offset = _offset, \
.cfg.flags = _flags, \
.cfg.hw.init = CLK_HW_INIT(_name, _parent, &clk_divider_ops, 0), \
.cfg.lock = &mpfs_clk_lock, \
}
#define CLK_CPU_OFFSET 0u
#define CLK_AXI_OFFSET 1u
#define CLK_AHB_OFFSET 2u
#define CLK_RTCREF_OFFSET 3u
static struct mpfs_cfg_hw_clock mpfs_cfg_clks[] = {
CLK_CFG(CLK_CPU, "clk_cpu", "clk_msspll", 0, 2, mpfs_div_cpu_axi_table, 0,
REG_CLOCK_CONFIG_CR),
CLK_CFG(CLK_AXI, "clk_axi", "clk_msspll", 2, 2, mpfs_div_cpu_axi_table, 0,
REG_CLOCK_CONFIG_CR),
CLK_CFG(CLK_AHB, "clk_ahb", "clk_msspll", 4, 2, mpfs_div_ahb_table, 0,
REG_CLOCK_CONFIG_CR),
{
.id = CLK_RTCREF,
.cfg.shift = 0,
.cfg.width = 12,
.cfg.table = mpfs_div_rtcref_table,
.reg_offset = REG_RTC_CLOCK_CR,
.cfg.flags = CLK_DIVIDER_ONE_BASED,
.cfg.hw.init =
CLK_HW_INIT_PARENTS_DATA("clk_rtcref", mpfs_ext_ref, &clk_divider_ops, 0),
}
};
static int mpfs_clk_register_cfgs(struct device *dev, struct mpfs_cfg_hw_clock *cfg_hws,
unsigned int num_clks, struct mpfs_clock_data *data)
{
unsigned int i, id;
int ret;
for (i = 0; i < num_clks; i++) {
struct mpfs_cfg_hw_clock *cfg_hw = &cfg_hws[i];
cfg_hw->cfg.reg = data->base + cfg_hw->reg_offset;
ret = devm_clk_hw_register(dev, &cfg_hw->cfg.hw);
if (ret)
return dev_err_probe(dev, ret, "failed to register clock id: %d\n",
cfg_hw->id);
id = cfg_hw->id;
data->hw_data.hws[id] = &cfg_hw->cfg.hw;
}
return 0;
}
/*
* peripheral clocks - devices connected to axi or ahb buses.
*/
#define CLK_PERIPH(_id, _name, _parent, _shift, _flags) { \
.id = _id, \
.periph.bit_idx = _shift, \
.periph.hw.init = CLK_HW_INIT_HW(_name, _parent, &clk_gate_ops, \
_flags), \
.periph.lock = &mpfs_clk_lock, \
}
#define PARENT_CLK(PARENT) (&mpfs_cfg_clks[CLK_##PARENT##_OFFSET].cfg.hw)
/*
* Critical clocks:
* - CLK_ENVM: reserved by hart software services (hss) superloop monitor/m mode interrupt
* trap handler
* - CLK_MMUART0: reserved by the hss
* - CLK_DDRC: provides clock to the ddr subsystem
* - CLK_RTC: the onboard RTC's AHB bus clock must be kept running as the rtc will stop
* if the AHB interface clock is disabled
* - CLK_FICx: these provide the processor side clocks to the "FIC" (Fabric InterConnect)
* clock domain crossers which provide the interface to the FPGA fabric. Disabling them
* causes the FPGA fabric to go into reset.
* - CLK_ATHENA: The athena clock is FIC4, which is reserved for the Athena TeraFire.
*/
static struct mpfs_periph_hw_clock mpfs_periph_clks[] = {
CLK_PERIPH(CLK_ENVM, "clk_periph_envm", PARENT_CLK(AHB), 0, CLK_IS_CRITICAL),
CLK_PERIPH(CLK_MAC0, "clk_periph_mac0", PARENT_CLK(AHB), 1, 0),
CLK_PERIPH(CLK_MAC1, "clk_periph_mac1", PARENT_CLK(AHB), 2, 0),
CLK_PERIPH(CLK_MMC, "clk_periph_mmc", PARENT_CLK(AHB), 3, 0),
CLK_PERIPH(CLK_TIMER, "clk_periph_timer", PARENT_CLK(RTCREF), 4, 0),
CLK_PERIPH(CLK_MMUART0, "clk_periph_mmuart0", PARENT_CLK(AHB), 5, CLK_IS_CRITICAL),
CLK_PERIPH(CLK_MMUART1, "clk_periph_mmuart1", PARENT_CLK(AHB), 6, 0),
CLK_PERIPH(CLK_MMUART2, "clk_periph_mmuart2", PARENT_CLK(AHB), 7, 0),
CLK_PERIPH(CLK_MMUART3, "clk_periph_mmuart3", PARENT_CLK(AHB), 8, 0),
CLK_PERIPH(CLK_MMUART4, "clk_periph_mmuart4", PARENT_CLK(AHB), 9, 0),
CLK_PERIPH(CLK_SPI0, "clk_periph_spi0", PARENT_CLK(AHB), 10, 0),
CLK_PERIPH(CLK_SPI1, "clk_periph_spi1", PARENT_CLK(AHB), 11, 0),
CLK_PERIPH(CLK_I2C0, "clk_periph_i2c0", PARENT_CLK(AHB), 12, 0),
CLK_PERIPH(CLK_I2C1, "clk_periph_i2c1", PARENT_CLK(AHB), 13, 0),
CLK_PERIPH(CLK_CAN0, "clk_periph_can0", PARENT_CLK(AHB), 14, 0),
CLK_PERIPH(CLK_CAN1, "clk_periph_can1", PARENT_CLK(AHB), 15, 0),
CLK_PERIPH(CLK_USB, "clk_periph_usb", PARENT_CLK(AHB), 16, 0),
CLK_PERIPH(CLK_RTC, "clk_periph_rtc", PARENT_CLK(AHB), 18, CLK_IS_CRITICAL),
CLK_PERIPH(CLK_QSPI, "clk_periph_qspi", PARENT_CLK(AHB), 19, 0),
CLK_PERIPH(CLK_GPIO0, "clk_periph_gpio0", PARENT_CLK(AHB), 20, 0),
CLK_PERIPH(CLK_GPIO1, "clk_periph_gpio1", PARENT_CLK(AHB), 21, 0),
CLK_PERIPH(CLK_GPIO2, "clk_periph_gpio2", PARENT_CLK(AHB), 22, 0),
CLK_PERIPH(CLK_DDRC, "clk_periph_ddrc", PARENT_CLK(AHB), 23, CLK_IS_CRITICAL),
CLK_PERIPH(CLK_FIC0, "clk_periph_fic0", PARENT_CLK(AXI), 24, CLK_IS_CRITICAL),
CLK_PERIPH(CLK_FIC1, "clk_periph_fic1", PARENT_CLK(AXI), 25, CLK_IS_CRITICAL),
CLK_PERIPH(CLK_FIC2, "clk_periph_fic2", PARENT_CLK(AXI), 26, CLK_IS_CRITICAL),
CLK_PERIPH(CLK_FIC3, "clk_periph_fic3", PARENT_CLK(AXI), 27, CLK_IS_CRITICAL),
CLK_PERIPH(CLK_ATHENA, "clk_periph_athena", PARENT_CLK(AXI), 28, CLK_IS_CRITICAL),
CLK_PERIPH(CLK_CFM, "clk_periph_cfm", PARENT_CLK(AHB), 29, 0),
};
static int mpfs_clk_register_periphs(struct device *dev, struct mpfs_periph_hw_clock *periph_hws,
int num_clks, struct mpfs_clock_data *data)
{
unsigned int i, id;
int ret;
for (i = 0; i < num_clks; i++) {
struct mpfs_periph_hw_clock *periph_hw = &periph_hws[i];
periph_hw->periph.reg = data->base + REG_SUBBLK_CLOCK_CR;
ret = devm_clk_hw_register(dev, &periph_hw->periph.hw);
if (ret)
return dev_err_probe(dev, ret, "failed to register clock id: %d\n",
periph_hw->id);
id = periph_hws[i].id;
data->hw_data.hws[id] = &periph_hw->periph.hw;
}
return 0;
}
/*
* Peripheral clock resets
*/
#if IS_ENABLED(CONFIG_RESET_CONTROLLER)
u32 mpfs_reset_read(struct device *dev)
{
struct mpfs_clock_data *clock_data = dev_get_drvdata(dev->parent);
return readl_relaxed(clock_data->base + REG_SUBBLK_RESET_CR);
}
EXPORT_SYMBOL_NS_GPL(mpfs_reset_read, MCHP_CLK_MPFS);
void mpfs_reset_write(struct device *dev, u32 val)
{
struct mpfs_clock_data *clock_data = dev_get_drvdata(dev->parent);
writel_relaxed(val, clock_data->base + REG_SUBBLK_RESET_CR);
}
EXPORT_SYMBOL_NS_GPL(mpfs_reset_write, MCHP_CLK_MPFS);
static void mpfs_reset_unregister_adev(void *_adev)
{
struct auxiliary_device *adev = _adev;
auxiliary_device_delete(adev);
}
static void mpfs_reset_adev_release(struct device *dev)
{
struct auxiliary_device *adev = to_auxiliary_dev(dev);
auxiliary_device_uninit(adev);
kfree(adev);
}
static struct auxiliary_device *mpfs_reset_adev_alloc(struct mpfs_clock_data *clk_data)
{
struct auxiliary_device *adev;
int ret;
adev = kzalloc(sizeof(*adev), GFP_KERNEL);
if (!adev)
return ERR_PTR(-ENOMEM);
adev->name = "reset-mpfs";
adev->dev.parent = clk_data->dev;
adev->dev.release = mpfs_reset_adev_release;
adev->id = 666u;
ret = auxiliary_device_init(adev);
if (ret) {
kfree(adev);
return ERR_PTR(ret);
}
return adev;
}
static int mpfs_reset_controller_register(struct mpfs_clock_data *clk_data)
{
struct auxiliary_device *adev;
int ret;
adev = mpfs_reset_adev_alloc(clk_data);
if (IS_ERR(adev))
return PTR_ERR(adev);
ret = auxiliary_device_add(adev);
if (ret) {
auxiliary_device_uninit(adev);
return ret;
}
return devm_add_action_or_reset(clk_data->dev, mpfs_reset_unregister_adev, adev);
}
#else /* !CONFIG_RESET_CONTROLLER */
static int mpfs_reset_controller_register(struct mpfs_clock_data *clk_data)
{
return 0;
}
#endif /* !CONFIG_RESET_CONTROLLER */
static int mpfs_clk_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct mpfs_clock_data *clk_data;
unsigned int num_clks;
int ret;
/* CLK_RESERVED is not part of clock arrays, so add 1 */
num_clks = ARRAY_SIZE(mpfs_msspll_clks) + ARRAY_SIZE(mpfs_cfg_clks)
+ ARRAY_SIZE(mpfs_periph_clks) + 1;
clk_data = devm_kzalloc(dev, struct_size(clk_data, hw_data.hws, num_clks), GFP_KERNEL);
if (!clk_data)
return -ENOMEM;
clk_data->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(clk_data->base))
return PTR_ERR(clk_data->base);
clk_data->msspll_base = devm_platform_ioremap_resource(pdev, 1);
if (IS_ERR(clk_data->msspll_base))
return PTR_ERR(clk_data->msspll_base);
clk_data->hw_data.num = num_clks;
clk_data->dev = dev;
dev_set_drvdata(dev, clk_data);
ret = mpfs_clk_register_mssplls(dev, mpfs_msspll_clks, ARRAY_SIZE(mpfs_msspll_clks),
clk_data);
if (ret)
return ret;
ret = mpfs_clk_register_cfgs(dev, mpfs_cfg_clks, ARRAY_SIZE(mpfs_cfg_clks), clk_data);
if (ret)
return ret;
ret = mpfs_clk_register_periphs(dev, mpfs_periph_clks, ARRAY_SIZE(mpfs_periph_clks),
clk_data);
if (ret)
return ret;
ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, &clk_data->hw_data);
if (ret)
return ret;
return mpfs_reset_controller_register(clk_data);
}
static const struct of_device_id mpfs_clk_of_match_table[] = {
{ .compatible = "microchip,mpfs-clkcfg", },
{}
};
MODULE_DEVICE_TABLE(of, mpfs_clk_of_match_table);
static struct platform_driver mpfs_clk_driver = {
.probe = mpfs_clk_probe,
.driver = {
.name = "microchip-mpfs-clkcfg",
.of_match_table = mpfs_clk_of_match_table,
},
};
static int __init clk_mpfs_init(void)
{
return platform_driver_register(&mpfs_clk_driver);
}
core_initcall(clk_mpfs_init);
static void __exit clk_mpfs_exit(void)
{
platform_driver_unregister(&mpfs_clk_driver);
}
module_exit(clk_mpfs_exit);
MODULE_DESCRIPTION("Microchip PolarFire SoC Clock Driver");
MODULE_LICENSE("GPL v2");
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