linux_dsm_epyc7002/drivers/clk/at91/pmc.c
Alexandre Belloni b3b02eac33 clk: at91: Add sama5d2 suspend/resume
On sama5d2, VDD core maybe be cut while in suspend. This means registers
will be lost. Ensure they are saved and restored properly.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2017-06-29 18:47:35 -07:00

173 lines
4.0 KiB
C

/*
* Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
*/
#include <linux/clk-provider.h>
#include <linux/clkdev.h>
#include <linux/clk/at91_pmc.h>
#include <linux/of.h>
#include <linux/mfd/syscon.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/syscore_ops.h>
#include <asm/proc-fns.h>
#include "pmc.h"
#define PMC_MAX_IDS 128
int of_at91_get_clk_range(struct device_node *np, const char *propname,
struct clk_range *range)
{
u32 min, max;
int ret;
ret = of_property_read_u32_index(np, propname, 0, &min);
if (ret)
return ret;
ret = of_property_read_u32_index(np, propname, 1, &max);
if (ret)
return ret;
if (range) {
range->min = min;
range->max = max;
}
return 0;
}
EXPORT_SYMBOL_GPL(of_at91_get_clk_range);
#ifdef CONFIG_PM
static struct regmap *pmcreg;
static u8 registered_ids[PMC_MAX_IDS];
static struct
{
u32 scsr;
u32 pcsr0;
u32 uckr;
u32 mor;
u32 mcfr;
u32 pllar;
u32 mckr;
u32 usb;
u32 imr;
u32 pcsr1;
u32 pcr[PMC_MAX_IDS];
u32 audio_pll0;
u32 audio_pll1;
} pmc_cache;
void pmc_register_id(u8 id)
{
int i;
for (i = 0; i < PMC_MAX_IDS; i++) {
if (registered_ids[i] == 0) {
registered_ids[i] = id;
break;
}
if (registered_ids[i] == id)
break;
}
}
static int pmc_suspend(void)
{
int i;
regmap_read(pmcreg, AT91_PMC_IMR, &pmc_cache.scsr);
regmap_read(pmcreg, AT91_PMC_PCSR, &pmc_cache.pcsr0);
regmap_read(pmcreg, AT91_CKGR_UCKR, &pmc_cache.uckr);
regmap_read(pmcreg, AT91_CKGR_MOR, &pmc_cache.mor);
regmap_read(pmcreg, AT91_CKGR_MCFR, &pmc_cache.mcfr);
regmap_read(pmcreg, AT91_CKGR_PLLAR, &pmc_cache.pllar);
regmap_read(pmcreg, AT91_PMC_MCKR, &pmc_cache.mckr);
regmap_read(pmcreg, AT91_PMC_USB, &pmc_cache.usb);
regmap_read(pmcreg, AT91_PMC_IMR, &pmc_cache.imr);
regmap_read(pmcreg, AT91_PMC_PCSR1, &pmc_cache.pcsr1);
for (i = 0; registered_ids[i]; i++) {
regmap_write(pmcreg, AT91_PMC_PCR,
(registered_ids[i] & AT91_PMC_PCR_PID_MASK));
regmap_read(pmcreg, AT91_PMC_PCR,
&pmc_cache.pcr[registered_ids[i]]);
}
return 0;
}
static void pmc_resume(void)
{
int i, ret = 0;
u32 tmp;
regmap_read(pmcreg, AT91_PMC_MCKR, &tmp);
if (pmc_cache.mckr != tmp)
pr_warn("MCKR was not configured properly by the firmware\n");
regmap_read(pmcreg, AT91_CKGR_PLLAR, &tmp);
if (pmc_cache.pllar != tmp)
pr_warn("PLLAR was not configured properly by the firmware\n");
regmap_write(pmcreg, AT91_PMC_IMR, pmc_cache.scsr);
regmap_write(pmcreg, AT91_PMC_PCER, pmc_cache.pcsr0);
regmap_write(pmcreg, AT91_CKGR_UCKR, pmc_cache.uckr);
regmap_write(pmcreg, AT91_CKGR_MOR, pmc_cache.mor);
regmap_write(pmcreg, AT91_CKGR_MCFR, pmc_cache.mcfr);
regmap_write(pmcreg, AT91_PMC_USB, pmc_cache.usb);
regmap_write(pmcreg, AT91_PMC_IMR, pmc_cache.imr);
regmap_write(pmcreg, AT91_PMC_PCER1, pmc_cache.pcsr1);
for (i = 0; registered_ids[i]; i++) {
regmap_write(pmcreg, AT91_PMC_PCR,
pmc_cache.pcr[registered_ids[i]] |
AT91_PMC_PCR_CMD);
}
if (pmc_cache.uckr & AT91_PMC_UPLLEN) {
ret = regmap_read_poll_timeout(pmcreg, AT91_PMC_SR, tmp,
!(tmp & AT91_PMC_LOCKU),
10, 5000);
if (ret)
pr_crit("USB PLL didn't lock when resuming\n");
}
}
static struct syscore_ops pmc_syscore_ops = {
.suspend = pmc_suspend,
.resume = pmc_resume,
};
static const struct of_device_id sama5d2_pmc_dt_ids[] = {
{ .compatible = "atmel,sama5d2-pmc" },
{ /* sentinel */ }
};
static int __init pmc_register_ops(void)
{
struct device_node *np;
np = of_find_matching_node(NULL, sama5d2_pmc_dt_ids);
pmcreg = syscon_node_to_regmap(np);
if (IS_ERR(pmcreg))
return PTR_ERR(pmcreg);
register_syscore_ops(&pmc_syscore_ops);
return 0;
}
/* This has to happen before arch_initcall because of the tcb_clksrc driver */
postcore_initcall(pmc_register_ops);
#endif