mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-12-22 19:23:07 +00:00
147 lines
3.3 KiB
C
147 lines
3.3 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* Copyright (C) 2018 Microhip / Atmel Corporation
|
|
* Wenyou.Yang <wenyou.yang@microchip.com>
|
|
*/
|
|
|
|
#include <common.h>
|
|
#include <clk-uclass.h>
|
|
#include <log.h>
|
|
#include <dm/device.h>
|
|
#include <linux/err.h>
|
|
#include <linux/io.h>
|
|
#include <mach/at91_pmc.h>
|
|
#include "pmc.h"
|
|
|
|
DECLARE_GLOBAL_DATA_PTR;
|
|
|
|
#define AT91_USB_CLK_SOURCE_MAX 2
|
|
#define AT91_USB_CLK_MAX_DIV 15
|
|
|
|
struct at91_usb_clk_priv {
|
|
u32 num_clksource;
|
|
};
|
|
|
|
static ulong at91_usb_clk_get_rate(struct clk *clk)
|
|
{
|
|
struct pmc_platdata *plat = dev_get_platdata(clk->dev);
|
|
struct at91_pmc *pmc = plat->reg_base;
|
|
struct clk source;
|
|
u32 tmp, usbdiv;
|
|
u8 source_index;
|
|
int ret;
|
|
|
|
tmp = readl(&pmc->pcr);
|
|
source_index = (tmp >> AT91_PMC_USB_USBS_OFFSET) &
|
|
AT91_PMC_USB_USBS_MASK;
|
|
usbdiv = (tmp >> AT91_PMC_USB_DIV_OFFSET) & AT91_PMC_USB_DIV_MASK;
|
|
|
|
ret = clk_get_by_index(clk->dev, source_index, &source);
|
|
if (ret)
|
|
return 0;
|
|
|
|
return clk_get_rate(&source) / (usbdiv + 1);
|
|
}
|
|
|
|
static ulong at91_usb_clk_set_rate(struct clk *clk, ulong rate)
|
|
{
|
|
struct pmc_platdata *plat = dev_get_platdata(clk->dev);
|
|
struct at91_pmc *pmc = plat->reg_base;
|
|
struct at91_usb_clk_priv *priv = dev_get_priv(clk->dev);
|
|
struct clk source, best_source;
|
|
ulong tmp_rate, best_rate = rate, source_rate;
|
|
int tmp_diff, best_diff = -1;
|
|
u32 div, best_div = 0;
|
|
u8 best_source_index = 0;
|
|
u8 i;
|
|
u32 tmp;
|
|
int ret;
|
|
|
|
for (i = 0; i < priv->num_clksource; i++) {
|
|
ret = clk_get_by_index(clk->dev, i, &source);
|
|
if (ret)
|
|
return ret;
|
|
|
|
source_rate = clk_get_rate(&source);
|
|
if (IS_ERR_VALUE(source_rate))
|
|
return source_rate;
|
|
|
|
for (div = 1; div < AT91_USB_CLK_MAX_DIV + 2; div++) {
|
|
tmp_rate = DIV_ROUND_CLOSEST(source_rate, div);
|
|
tmp_diff = abs(rate - tmp_rate);
|
|
|
|
if (best_diff < 0 || best_diff > tmp_diff) {
|
|
best_rate = tmp_rate;
|
|
best_diff = tmp_diff;
|
|
|
|
best_div = div - 1;
|
|
best_source = source;
|
|
best_source_index = i;
|
|
}
|
|
|
|
if (!best_diff || tmp_rate < rate)
|
|
break;
|
|
}
|
|
|
|
if (!best_diff)
|
|
break;
|
|
}
|
|
|
|
debug("AT91 USB: best sourc: %s, best_rate = %ld, best_div = %d\n",
|
|
best_source.dev->name, best_rate, best_div);
|
|
|
|
ret = clk_enable(&best_source);
|
|
if (ret)
|
|
return ret;
|
|
|
|
tmp = AT91_PMC_USB_USBS_(best_source_index) |
|
|
AT91_PMC_USB_DIV_(best_div);
|
|
writel(tmp, &pmc->usb);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct clk_ops at91_usb_clk_ops = {
|
|
.get_rate = at91_usb_clk_get_rate,
|
|
.set_rate = at91_usb_clk_set_rate,
|
|
};
|
|
|
|
static int at91_usb_clk_ofdata_to_platdata(struct udevice *dev)
|
|
{
|
|
struct at91_usb_clk_priv *priv = dev_get_priv(dev);
|
|
u32 cells[AT91_USB_CLK_SOURCE_MAX];
|
|
u32 num_clksource;
|
|
|
|
num_clksource = fdtdec_get_int_array_count(gd->fdt_blob,
|
|
dev_of_offset(dev),
|
|
"clocks", cells,
|
|
AT91_USB_CLK_SOURCE_MAX);
|
|
|
|
if (!num_clksource)
|
|
return -1;
|
|
|
|
priv->num_clksource = num_clksource;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int at91_usb_clk_probe(struct udevice *dev)
|
|
{
|
|
return at91_pmc_core_probe(dev);
|
|
}
|
|
|
|
static const struct udevice_id at91_usb_clk_match[] = {
|
|
{ .compatible = "atmel,at91sam9x5-clk-usb" },
|
|
{}
|
|
};
|
|
|
|
U_BOOT_DRIVER(at91_usb_clk) = {
|
|
.name = "at91-usb-clk",
|
|
.id = UCLASS_CLK,
|
|
.of_match = at91_usb_clk_match,
|
|
.probe = at91_usb_clk_probe,
|
|
.ofdata_to_platdata = at91_usb_clk_ofdata_to_platdata,
|
|
.priv_auto_alloc_size = sizeof(struct at91_usb_clk_priv),
|
|
.platdata_auto_alloc_size = sizeof(struct pmc_platdata),
|
|
.ops = &at91_usb_clk_ops,
|
|
};
|