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clk: at91: pmc: execute suspend/resume only for backup mode

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Before going to backup mode architecture specific PM code sets the first
word in securam (file arch/arm/mach-at91/pm.c, function at91_pm_begin()).
Thus take this into account when suspending/resuming clocks. This will
avoid executing unnecessary instructions when suspending to non backup
modes.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20211011112719.3951784-3-claudiu.beznea@microchip.com
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
This commit is contained in:
Claudiu Beznea 2021-10-11 14:27:06 +03:00 committed by Stephen Boyd
parent 36971566ea
commit 4d21be8640
1 changed files with 39 additions and 0 deletions
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39
drivers/clk/at91/pmc.c
View File

@ -8,6 +8,7 @@
#include <linux/clkdev.h>
#include <linux/clk/at91_pmc.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/mfd/syscon.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
@ -110,13 +111,35 @@ struct pmc_data *pmc_data_allocate(unsigned int ncore, unsigned int nsystem,
}
#ifdef CONFIG_PM
/* Address in SECURAM that say if we suspend to backup mode. */
static void __iomem *at91_pmc_backup_suspend;
static int at91_pmc_suspend(void)
{
unsigned int backup;
if (!at91_pmc_backup_suspend)
return 0;
backup = readl_relaxed(at91_pmc_backup_suspend);
if (!backup)
return 0;
return clk_save_context();
}
static void at91_pmc_resume(void)
{
unsigned int backup;
if (!at91_pmc_backup_suspend)
return;
backup = readl_relaxed(at91_pmc_backup_suspend);
if (!backup)
return;
clk_restore_context();
}
@ -144,6 +167,22 @@ static int __init pmc_register_ops(void)
}
of_node_put(np);
np = of_find_compatible_node(NULL, NULL, "atmel,sama5d2-securam");
if (!np)
return -ENODEV;
if (!of_device_is_available(np)) {
of_node_put(np);
return -ENODEV;
}
of_node_put(np);
at91_pmc_backup_suspend = of_iomap(np, 0);
if (!at91_pmc_backup_suspend) {
pr_warn("%s(): unable to map securam\n", __func__);
return -ENOMEM;
}
register_syscore_ops(&pmc_syscore_ops);
return 0;