blob: aed7d22fae63130999d7888068407a91792a9134 [file] [log] [blame]
// SPDX-License-Identifier: MIT
/*
* clock framework for AMD FCH controller block
*
* Copyright 2018 Advanced Micro Devices, Inc.
*/
#include <linux/clk.h>
#include <linux/clkdev.h>
#include <linux/clk-provider.h>
#include <linux/pci.h>
#include <linux/platform_data/clk-fch.h>
#include <linux/platform_device.h>
/* Clock Driving Strength 2 register */
#define CLKDRVSTR2 0x28
/* Clock Control 1 register */
#define MISCCLKCNTL1 0x40
/* Auxiliary clock1 enable bit */
#define OSCCLKENB 2
/* 25Mhz auxiliary output clock freq bit */
#define OSCOUT1CLK25MHZ 16
#define ST_CLK_48M 0
#define ST_CLK_25M 1
#define ST_CLK_MUX 2
#define ST_CLK_GATE 3
#define ST_MAX_CLKS 4
#define CLK_48M_FIXED 0
#define CLK_GATE_FIXED 1
#define CLK_MAX_FIXED 2
/* List of supported CPU ids for clk mux with 25Mhz clk support */
#define AMD_CPU_ID_ST 0x1576
static const char * const clk_oscout1_parents[] = { "clk48MHz", "clk25MHz" };
static struct clk_hw *hws[ST_MAX_CLKS];
static const struct pci_device_id fch_pci_ids[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_CPU_ID_ST) },
{ }
};
static int fch_clk_probe(struct platform_device *pdev)
{
struct fch_clk_data *fch_data;
struct pci_dev *rdev;
fch_data = dev_get_platdata(&pdev->dev);
if (!fch_data || !fch_data->base)
return -EINVAL;
rdev = pci_get_domain_bus_and_slot(0, 0, PCI_DEVFN(0, 0));
if (!rdev) {
dev_err(&pdev->dev, "FCH device not found\n");
return -ENODEV;
}
if (pci_match_id(fch_pci_ids, rdev)) {
hws[ST_CLK_48M] = clk_hw_register_fixed_rate(NULL, "clk48MHz",
NULL, 0, 48000000);
hws[ST_CLK_25M] = clk_hw_register_fixed_rate(NULL, "clk25MHz",
NULL, 0, 25000000);
hws[ST_CLK_MUX] = clk_hw_register_mux(NULL, "oscout1_mux",
clk_oscout1_parents, ARRAY_SIZE(clk_oscout1_parents),
0, fch_data->base + CLKDRVSTR2, OSCOUT1CLK25MHZ, 3, 0,
NULL);
clk_set_parent(hws[ST_CLK_MUX]->clk, hws[ST_CLK_48M]->clk);
hws[ST_CLK_GATE] = clk_hw_register_gate(NULL, "oscout1",
"oscout1_mux", 0, fch_data->base + MISCCLKCNTL1,
OSCCLKENB, CLK_GATE_SET_TO_DISABLE, NULL);
devm_clk_hw_register_clkdev(&pdev->dev, hws[ST_CLK_GATE],
fch_data->name, NULL);
} else {
hws[CLK_48M_FIXED] = clk_hw_register_fixed_rate(NULL, "clk48MHz",
NULL, 0, 48000000);
hws[CLK_GATE_FIXED] = clk_hw_register_gate(NULL, "oscout1",
"clk48MHz", 0, fch_data->base + MISCCLKCNTL1,
OSCCLKENB, 0, NULL);
devm_clk_hw_register_clkdev(&pdev->dev, hws[CLK_GATE_FIXED],
fch_data->name, NULL);
}
pci_dev_put(rdev);
return 0;
}
static void fch_clk_remove(struct platform_device *pdev)
{
int i, clks;
struct pci_dev *rdev;
rdev = pci_get_domain_bus_and_slot(0, 0, PCI_DEVFN(0, 0));
if (!rdev)
return;
clks = pci_match_id(fch_pci_ids, rdev) ? CLK_MAX_FIXED : ST_MAX_CLKS;
for (i = 0; i < clks; i++)
clk_hw_unregister(hws[i]);
pci_dev_put(rdev);
}
static struct platform_driver fch_clk_driver = {
.driver = {
.name = "clk-fch",
.suppress_bind_attrs = true,
},
.probe = fch_clk_probe,
.remove_new = fch_clk_remove,
};
builtin_platform_driver(fch_clk_driver);