u-boot/drivers/clk/at91/clk-peripheral.c
Claudiu Beznea f89268e468 clk: at91: clk-peripheral: add driver compatible with ccf
Add clk-peripheral compatible with common clock framework.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
2020-09-22 11:27:18 +03:00

254 lines
6 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Peripheral clock support for AT91 architectures.
*
* Copyright (C) 2020 Microchip Technology Inc. and its subsidiaries
*
* Author: Claudiu Beznea <claudiu.beznea@microchip.com>
*
* Based on drivers/clk/at91/clk-peripheral.c from Linux.
*/
#include <common.h>
#include <clk-uclass.h>
#include <dm.h>
#include <linux/io.h>
#include <linux/clk-provider.h>
#include <linux/clk/at91_pmc.h>
#include "pmc.h"
#define UBOOT_DM_CLK_AT91_PERIPH "at91-periph-clk"
#define UBOOT_DM_CLK_AT91_SAM9X5_PERIPH "at91-sam9x5-periph-clk"
#define PERIPHERAL_ID_MIN 2
#define PERIPHERAL_ID_MAX 31
#define PERIPHERAL_MASK(id) (1 << ((id) & PERIPHERAL_ID_MAX))
#define PERIPHERAL_MAX_SHIFT 3
struct clk_peripheral {
void __iomem *base;
struct clk clk;
u32 id;
};
#define to_clk_peripheral(_c) container_of(_c, struct clk_peripheral, clk)
struct clk_sam9x5_peripheral {
const struct clk_pcr_layout *layout;
void __iomem *base;
struct clk clk;
struct clk_range range;
u32 id;
u32 div;
bool auto_div;
};
#define to_clk_sam9x5_peripheral(_c) \
container_of(_c, struct clk_sam9x5_peripheral, clk)
static int clk_peripheral_enable(struct clk *clk)
{
struct clk_peripheral *periph = to_clk_peripheral(clk);
int offset = AT91_PMC_PCER;
u32 id = periph->id;
if (id < PERIPHERAL_ID_MIN)
return 0;
if (id > PERIPHERAL_ID_MAX)
offset = AT91_PMC_PCER1;
pmc_write(periph->base, offset, PERIPHERAL_MASK(id));
return 0;
}
static int clk_peripheral_disable(struct clk *clk)
{
struct clk_peripheral *periph = to_clk_peripheral(clk);
int offset = AT91_PMC_PCDR;
u32 id = periph->id;
if (id < PERIPHERAL_ID_MIN)
return -EINVAL;
if (id > PERIPHERAL_ID_MAX)
offset = AT91_PMC_PCDR1;
pmc_write(periph->base, offset, PERIPHERAL_MASK(id));
return 0;
}
static const struct clk_ops peripheral_ops = {
.enable = clk_peripheral_enable,
.disable = clk_peripheral_disable,
.get_rate = clk_generic_get_rate,
};
struct clk *
at91_clk_register_peripheral(void __iomem *base, const char *name,
const char *parent_name, u32 id)
{
struct clk_peripheral *periph;
struct clk *clk;
int ret;
if (!base || !name || !parent_name || id > PERIPHERAL_ID_MAX)
return ERR_PTR(-EINVAL);
periph = kzalloc(sizeof(*periph), GFP_KERNEL);
if (!periph)
return ERR_PTR(-ENOMEM);
periph->id = id;
periph->base = base;
clk = &periph->clk;
clk->flags = CLK_GET_RATE_NOCACHE;
ret = clk_register(clk, UBOOT_DM_CLK_AT91_PERIPH, name, parent_name);
if (ret) {
kfree(periph);
clk = ERR_PTR(ret);
}
return clk;
}
U_BOOT_DRIVER(at91_periph_clk) = {
.name = UBOOT_DM_CLK_AT91_PERIPH,
.id = UCLASS_CLK,
.ops = &peripheral_ops,
.flags = DM_FLAG_PRE_RELOC,
};
static int clk_sam9x5_peripheral_enable(struct clk *clk)
{
struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(clk);
if (periph->id < PERIPHERAL_ID_MIN)
return 0;
pmc_write(periph->base, periph->layout->offset,
(periph->id & periph->layout->pid_mask));
pmc_update_bits(periph->base, periph->layout->offset,
periph->layout->cmd | AT91_PMC_PCR_EN,
periph->layout->cmd | AT91_PMC_PCR_EN);
return 0;
}
static int clk_sam9x5_peripheral_disable(struct clk *clk)
{
struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(clk);
if (periph->id < PERIPHERAL_ID_MIN)
return -EINVAL;
pmc_write(periph->base, periph->layout->offset,
(periph->id & periph->layout->pid_mask));
pmc_update_bits(periph->base, periph->layout->offset,
AT91_PMC_PCR_EN | periph->layout->cmd,
periph->layout->cmd);
return 0;
}
static ulong clk_sam9x5_peripheral_get_rate(struct clk *clk)
{
struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(clk);
ulong parent_rate = clk_get_parent_rate(clk);
u32 val, shift = ffs(periph->layout->div_mask) - 1;
if (!parent_rate)
return 0;
pmc_write(periph->base, periph->layout->offset,
(periph->id & periph->layout->pid_mask));
pmc_read(periph->base, periph->layout->offset, &val);
shift = (val & periph->layout->div_mask) >> shift;
return parent_rate >> shift;
}
static ulong clk_sam9x5_peripheral_set_rate(struct clk *clk, ulong rate)
{
struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(clk);
ulong parent_rate = clk_get_parent_rate(clk);
int shift;
if (!parent_rate)
return 0;
if (periph->id < PERIPHERAL_ID_MIN || !periph->range.max) {
if (parent_rate == rate)
return rate;
else
return 0;
}
if (periph->range.max && rate > periph->range.max)
return 0;
for (shift = 0; shift <= PERIPHERAL_MAX_SHIFT; shift++) {
if (parent_rate >> shift <= rate)
break;
}
if (shift == PERIPHERAL_MAX_SHIFT + 1)
return 0;
pmc_write(periph->base, periph->layout->offset,
(periph->id & periph->layout->pid_mask));
pmc_update_bits(periph->base, periph->layout->offset,
periph->layout->div_mask | periph->layout->cmd,
(shift << (ffs(periph->layout->div_mask) - 1)) |
periph->layout->cmd);
return parent_rate >> shift;
}
static const struct clk_ops sam9x5_peripheral_ops = {
.enable = clk_sam9x5_peripheral_enable,
.disable = clk_sam9x5_peripheral_disable,
.get_rate = clk_sam9x5_peripheral_get_rate,
.set_rate = clk_sam9x5_peripheral_set_rate,
};
struct clk *
at91_clk_register_sam9x5_peripheral(void __iomem *base,
const struct clk_pcr_layout *layout,
const char *name, const char *parent_name,
u32 id, const struct clk_range *range)
{
struct clk_sam9x5_peripheral *periph;
struct clk *clk;
int ret;
if (!base || !layout || !name || !parent_name || !range)
return ERR_PTR(-EINVAL);
periph = kzalloc(sizeof(*periph), GFP_KERNEL);
if (!periph)
return ERR_PTR(-ENOMEM);
periph->id = id;
periph->base = base;
periph->layout = layout;
periph->range = *range;
clk = &periph->clk;
clk->flags = CLK_GET_RATE_NOCACHE;
ret = clk_register(clk, UBOOT_DM_CLK_AT91_SAM9X5_PERIPH, name,
parent_name);
if (ret) {
kfree(periph);
clk = ERR_PTR(ret);
}
return clk;
}
U_BOOT_DRIVER(at91_sam9x5_periph_clk) = {
.name = UBOOT_DM_CLK_AT91_SAM9X5_PERIPH,
.id = UCLASS_CLK,
.ops = &sam9x5_peripheral_ops,
.flags = DM_FLAG_PRE_RELOC,
};