// SPDX-License-Identifier: GPL-2.0
/*
* AM33XX Power Management Routines
*
* Copyright (C) 2012-2018 Texas Instruments Incorporated - http://www.ti.com/
* Vaibhav Bedia, Dave Gerlach
*/
#include <linux/clk.h>
#include <linux/cpu.h>
#include <linux/err.h>
#include <linux/genalloc.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/nvmem-consumer.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/platform_data/pm33xx.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/rtc.h>
#include <linux/rtc/rtc-omap.h>
#include <linux/sizes.h>
#include <linux/sram.h>
#include <linux/suspend.h>
#include <linux/ti-emif-sram.h>
#include <linux/wkup_m3_ipc.h>
#include <asm/proc-fns.h>
#include <asm/suspend.h>
#include <asm/system_misc.h>
#define AMX3_PM_SRAM_SYMBOL_OFFSET(sym) ((unsigned long)(sym) - \
(unsigned long)pm_sram->do_wfi)
#define RTC_SCRATCH_RESUME_REG 0
#define RTC_SCRATCH_MAGIC_REG 1
#define RTC_REG_BOOT_MAGIC 0x8cd0 /* RTC */
#define GIC_INT_SET_PENDING_BASE 0x200
#define AM43XX_GIC_DIST_BASE 0x48241000
static void __iomem *rtc_base_virt;
static struct clk *rtc_fck;
static u32 rtc_magic_val;
static int (*am33xx_do_wfi_sram)(unsigned long unused);
static phys_addr_t am33xx_do_wfi_sram_phys;
static struct gen_pool *sram_pool, *sram_pool_data;
static unsigned long ocmcram_location, ocmcram_location_data;
static struct rtc_device *omap_rtc;
static void __iomem *gic_dist_base;
static struct am33xx_pm_platform_data *pm_ops;
static struct am33xx_pm_sram_addr *pm_sram;
static struct device *pm33xx_dev;
static struct wkup_m3_ipc *m3_ipc;
#ifdef CONFIG_SUSPEND
static int rtc_only_idle;
static int retrigger_irq;
static unsigned long suspend_wfi_flags;
static struct wkup_m3_wakeup_src wakeup_src = {.irq_nr = 0,
.src = "Unknown",
};
static struct wkup_m3_wakeup_src rtc_alarm_wakeup = {
.irq_nr = 108, .src = "RTC Alarm",
};
static struct wkup_m3_wakeup_src rtc_ext_wakeup = {
.irq_nr = 0, .src = "Ext wakeup",
};
#endif
static u32 sram_suspend_address(unsigned long addr)
{
return ((unsigned long)am33xx_do_wfi_sram +
AMX3_PM_SRAM_SYMBOL_OFFSET(addr));
}
static int am33xx_push_sram_idle(void)
{
struct am33xx_pm_ro_sram_data ro_sram_data;
int ret;
u32 table_addr, ro_data_addr;
void *copy_addr;
ro_sram_data.amx3_pm_sram_data_virt = ocmcram_location_data;
ro_sram_data.amx3_pm_sram_data_phys =
gen_pool_virt_to_phys(sram_pool_data, ocmcram_location_data);
ro_sram_data.rtc_base_virt = rtc_base_virt;
/* Save physical address to calculate resume offset during pm init */
am33xx_do_wfi_sram_phys = gen_pool_virt_to_phys(sram_pool,
ocmcram_location);
am33xx_do_wfi_sram = sram_exec_copy(sram_pool, (void *)ocmcram_location,
pm_sram->do_wfi,
*pm_sram->do_wfi_sz);
if (!am33xx_do_wfi_sram) {
dev_err(pm33xx_dev,
"PM: %s: am33xx_do_wfi copy to sram failed\n",
__func__);
return -ENODEV;
}
table_addr =
sram_suspend_address((unsigned long)pm_sram->emif_sram_table);
ret = ti_emif_copy_pm_function_table(sram_pool, (void *)table_addr);
if (ret) {
dev_dbg(pm33xx_dev,
"PM: %s: EMIF function copy failed\n", __func__);
return -EPROBE_DEFER;
}
ro_data_addr =
sram_suspend_address((unsigned long)pm_sram->ro_sram_data);
copy_addr = sram_exec_copy(sram_pool, (void *)ro_data_addr,
&ro_sram_data,
sizeof(ro_sram_data));
if (!copy_addr) {
dev_err(pm33xx_dev,
"PM: %s: ro_sram_data copy to sram failed\n",
__func__);
return -ENODEV;
}
return 0;
}
static int am33xx_do_sram_idle(u32 wfi_flags)
{
if (!m3_ipc || !pm_ops)
return 0;
if (wfi_flags & WFI_FLAG_WAKE_M3)
m3_ipc->ops->prepare_low_power(m3_ipc, WKUP_M3_IDLE);
return pm_ops->cpu_suspend(am33xx_do_wfi_sram, wfi_flags);
}
static int __init am43xx_map_gic(void)
{
gic_dist_base = ioremap(AM43XX_GIC_DIST_BASE, SZ_4K);
if (!gic_dist_base)
return -ENOMEM;
return 0;
}
#ifdef CONFIG_SUSPEND
static struct wkup_m3_wakeup_src rtc_wake_src(void)
{
u32 i;
i = __raw_readl(rtc_base_virt + 0x44) & 0x40;
if (i) {
retrigger_irq = rtc_alarm_wakeup.irq_nr;
return rtc_alarm_wakeup;
}
retrigger_irq = rtc_ext_wakeup.irq_nr;
return rtc_ext_wakeup;
}
static int am33xx_rtc_only_idle(unsigned long wfi_flags)
{
omap_rtc_power_off_program(&omap_rtc->dev);
am33xx_do_wfi_sram(wfi_flags);
return 0;
}
/*
* Note that the RTC module clock must be re-enabled only for rtc+ddr suspend.
* And looks like the module can stay in SYSC_IDLE_SMART_WKUP mode configured
* by the interconnect code just fine for both rtc+ddr suspend and retention
* suspend.
*/
static int am33xx_pm_suspend(suspend_state_t suspend_state)
{
int i, ret = 0;
if (suspend_state == PM_SUSPEND_MEM &&
pm_ops->check_off_mode_enable()) {
ret = clk_prepare_enable(rtc_fck);
if (ret) {
dev_err(pm33xx_dev, "Failed to enable clock: %i\n", ret);
return ret;
}
pm_ops->save_context();
suspend_wfi_flags |= WFI_FLAG_RTC_ONLY;
clk_save_context();
ret = pm_ops->soc_suspend(suspend_state, am33xx_rtc_only_idle,
suspend_wfi_flags);
suspend_wfi_flags &= ~WFI_FLAG_RTC_ONLY;
dev_info(pm33xx_dev, "Entering RTC Only mode with DDR in self-refresh\n");
if (!ret) {
clk_restore_context();
pm_ops->restore_context();
m3_ipc->ops->set_rtc_only(m3_ipc);
am33xx_push_sram_idle();
}
} else {
ret = pm_ops->soc_suspend(suspend_state, am33xx_do_wfi_sram,
suspend_wfi_flags);
}
if (ret) {
dev_err(pm33xx_dev, "PM: Kernel suspend failure\n");
} else {
i = m3_ipc->ops->request_pm_status(m3_ipc);
switch (i) {
case 0:
dev_info(pm33xx_dev,
"PM: Successfully put all powerdomains to target state\n");
break;
case 1:
dev_err(pm33xx_dev,
"PM: Could not transition all powerdomains to target state\n");
ret = -1;
break;
default:
dev_err(pm33xx_dev,
"PM: CM3 returned unknown result = %d\n", i);
ret = -1;
}
/* print the wakeup reason */
if (rtc_only_idle) {
wakeup_src = rtc_wake_src();
pr_info("PM: Wakeup source %s\n", wakeup_src.src);
} else {
pr_info("PM: Wakeup source %s\n",
m3_ipc->ops->request_wake_src(m3_ipc));
}
}
if (suspend_state == PM_SUSPEND_MEM && pm_ops->check_off_mode_enable())
clk_disable_unprepare(rtc_fck);
return ret;
}
static int am33xx_pm_enter(suspend_state_t suspend_state)
{
int ret = 0;
switch (suspend_state) {
case PM_SUSPEND_MEM:
case PM_SUSPEND_STANDBY:
ret = am33xx_pm_suspend(suspend_state);
break;
default:
ret = -EINVAL;
}
return ret;
}
static int am33xx_pm_begin(suspend_state_t state)
{
int ret = -EINVAL;
struct nvmem_device *nvmem;
if (state == PM_SUSPEND_MEM && pm_ops->check_off_mode_enable()) {
nvmem = devm_nvmem_device_get(&omap_rtc->dev,
"omap_rtc_scratch0");
if (!IS_ERR(nvmem))
nvmem_device_write(nvmem, RTC_SCRATCH_MAGIC_REG * 4, 4,
(void *)&rtc_magic_val);
rtc_only_idle = 1;
} else {
rtc_only_idle = 0;
}
pm_ops->begin_suspend();
switch (state) {
case PM_SUSPEND_MEM:
ret = m3_ipc->ops->prepare_low_power(m3_ipc, WKUP_M3_DEEPSLEEP);
break;
case PM_SUSPEND_STANDBY:
ret = m3_ipc->ops->prepare_low_power(m3_ipc, WKUP_M3_STANDBY);
break;
}
return ret;
}
static void am33xx_pm_end(void)
{
u32 val = 0;
struct nvmem_device *nvmem;
nvmem = devm_nvmem_device_get(&omap_rtc->dev, "omap_rtc_scratch0");
if (IS_ERR(nvmem))
return;
m3_ipc->ops->finish_low_power(m3_ipc);
if (rtc_only_idle) {
if (retrigger_irq) {
/*
* 32 bits of Interrupt Set-Pending correspond to 32
* 32 interrupts. Compute the bit offset of the
* Interrupt and set that particular bit
* Compute the register offset by dividing interrupt
* number by 32 and mutiplying by 4
*/
writel_relaxed(1 << (retrigger_irq & 31),
gic_dist_base + GIC_INT_SET_PENDING_BASE
+ retrigger_irq / 32 * 4);
}
nvmem_device_write(nvmem, RTC_SCRATCH_MAGIC_REG * 4, 4,
(void *)&val);
}
rtc_only_idle = 0;
pm_ops->finish_suspend();
}
static int am33xx_pm_valid(suspend_state_t state)
{
switch (state) {
case PM_SUSPEND_STANDBY:
case PM_SUSPEND_MEM:
return 1;
default:
return 0;
}
}
static const struct platform_suspend_ops am33xx_pm_ops = {
.begin = am33xx_pm_begin,
.end = am33xx_pm_end,
.enter = am33xx_pm_enter,
.valid = am33xx_pm_valid,
};
#endif /* CONFIG_SUSPEND */
static void am33xx_pm_set_ipc_ops(void)
{
u32 resume_address;
int temp;
temp = ti_emif_get_mem_type();
if (temp < 0) {
dev_err(pm33xx_dev, "PM: Cannot determine memory type, no PM available\n");
return;
}
m3_ipc->ops->set_mem_type(m3_ipc, temp);
/* Physical resume address to be used by ROM code */
resume_address = am33xx_do_wfi_sram_phys +
*pm_sram->resume_offset + 0x4;
m3_ipc->ops->set_resume_address(m3_ipc, (void *)resume_address);
}
static void am33xx_pm_free_sram(void)
{
gen_pool_free(sram_pool, ocmcram_location, *pm_sram->do_wfi_sz);
gen_pool_free(sram_pool_data, ocmcram_location_data,
sizeof(struct am33xx_pm_ro_sram_data));
}
/*
* Push the minimal suspend-resume code to SRAM
*/
static int am33xx_pm_alloc_sram(void)
{
struct device_node *np;
int ret = 0;
np = of_find_compatible_node(NULL, NULL, "ti,omap3-mpu");
if (!np) {
np = of_find_compatible_node(NULL, NULL, "ti,omap4-mpu");
if (!np) {
dev_err(pm33xx_dev, "PM: %s: Unable to find device node for mpu\n",
__func__);
return -ENODEV;
}
}
sram_pool = of_gen_pool_get(np, "pm-sram", 0);
if (!sram_pool) {
dev_err(pm33xx_dev, "PM: %s: Unable to get sram pool for ocmcram\n",
__func__);
ret = -ENODEV;
goto mpu_put_node;
}
sram_pool_data = of_gen_pool_get(np, "pm-sram", 1);
if (!sram_pool_data) {
dev_err(pm33xx_dev, "PM: %s: Unable to get sram data pool for ocmcram\n",
__func__);
ret = -ENODEV;
goto mpu_put_node;
}
ocmcram_location = gen_pool_alloc(sram_pool, *pm_sram->do_wfi_sz);
if (!ocmcram_location) {
dev_err(pm33xx_dev, "PM: %s: Unable to allocate memory from ocmcram\n",
__func__);
ret = -ENOMEM;
goto mpu_put_node;
}
ocmcram_location_data = gen_pool_alloc(sram_pool_data,
sizeof(struct emif_regs_amx3));
if (!ocmcram_location_data) {
dev_err(pm33xx_dev, "PM: Unable to allocate memory from ocmcram\n");
gen_pool_free(sram_pool, ocmcram_location, *pm_sram->do_wfi_sz);
ret = -ENOMEM;
}
mpu_put_node:
of_node_put(np);
return ret;
}
static int am33xx_pm_rtc_setup(void)
{
struct device_node *np;
unsigned long val = 0;
struct nvmem_device *nvmem;
int error;
np = of_find_node_by_name(NULL, "rtc");
if (of_device_is_available(np)) {
/* RTC interconnect target module clock */
rtc_fck = of_clk_get_by_name(np->parent, "fck");
if (IS_ERR(rtc_fck))
return PTR_ERR(rtc_fck);
rtc_base_virt = of_iomap(np, 0);
if (!rtc_base_virt) {
pr_warn("PM: could not iomap rtc\n");
error = -ENODEV;
goto err_clk_put;
}
omap_rtc = rtc_class_open("rtc0");
if (!omap_rtc) {
pr_warn("PM: rtc0 not available\n");
error = -EPROBE_DEFER;
goto err_iounmap;
}
nvmem = devm_nvmem_device_get(&omap_rtc->dev,
"omap_rtc_scratch0");
if (!IS_ERR(nvmem)) {
nvmem_device_read(nvmem, RTC_SCRATCH_MAGIC_REG * 4,
4, (void *)&rtc_magic_val);
if ((rtc_magic_val & 0xffff) != RTC_REG_BOOT_MAGIC)
pr_warn("PM: bootloader does not support rtc-only!\n");
nvmem_device_write(nvmem, RTC_SCRATCH_MAGIC_REG * 4,
4, (void *)&val);
val = pm_sram->resume_address;
nvmem_device_write(nvmem, RTC_SCRATCH_RESUME_REG * 4,
4, (void *)&val);
}
} else {
pr_warn("PM: no-rtc available, rtc-only mode disabled.\n");
}
return 0;
err_iounmap:
iounmap(rtc_base_virt);
err_clk_put:
clk_put(rtc_fck);
return error;
}
static int am33xx_pm_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
int ret;
if (!of_machine_is_compatible("ti,am33xx") &&
!of_machine_is_compatible("ti,am43"))
return -ENODEV;
pm_ops = dev->platform_data;
if (!pm_ops) {
dev_err(dev, "PM: Cannot get core PM ops!\n");
return -ENODEV;
}
ret = am43xx_map_gic();
if (ret) {
pr_err("PM: Could not ioremap GIC base\n");
return ret;
}
pm_sram = pm_ops->get_sram_addrs();
if (!pm_sram) {
dev_err(dev, "PM: Cannot get PM asm function addresses!!\n");
return -ENODEV;
}
m3_ipc = wkup_m3_ipc_get();
if (!m3_ipc) {
pr_err("PM: Cannot get wkup_m3_ipc handle\n");
return -EPROBE_DEFER;
}
pm33xx_dev = dev;
ret = am33xx_pm_alloc_sram();
if (ret)
goto err_wkup_m3_ipc_put;
ret = am33xx_pm_rtc_setup();
if (ret)
goto err_free_sram;
ret = am33xx_push_sram_idle();
if (ret)
goto err_unsetup_rtc;
am33xx_pm_set_ipc_ops();
#ifdef CONFIG_SUSPEND
suspend_set_ops(&am33xx_pm_ops);
/*
* For a system suspend we must flush the caches, we want
* the DDR in self-refresh, we want to save the context
* of the EMIF, and we want the wkup_m3 to handle low-power
* transition.
*/
suspend_wfi_flags |= WFI_FLAG_FLUSH_CACHE;
suspend_wfi_flags |= WFI_FLAG_SELF_REFRESH;
suspend_wfi_flags |= WFI_FLAG_SAVE_EMIF;
suspend_wfi_flags |= WFI_FLAG_WAKE_M3;
#endif /* CONFIG_SUSPEND */
pm_runtime_enable(dev);
ret = pm_runtime_resume_and_get(dev);
if (ret < 0)
goto err_pm_runtime_disable;
ret = pm_ops->init(am33xx_do_sram_idle);
if (ret) {
dev_err(dev, "Unable to call core pm init!\n");
ret = -ENODEV;
goto err_pm_runtime_put;
}
return 0;
err_pm_runtime_put:
pm_runtime_put_sync(dev);
err_pm_runtime_disable:
pm_runtime_disable(dev);
err_unsetup_rtc:
iounmap(rtc_base_virt);
clk_put(rtc_fck);
err_free_sram:
am33xx_pm_free_sram();
pm33xx_dev = NULL;
err_wkup_m3_ipc_put:
wkup_m3_ipc_put(m3_ipc);
return ret;
}
static void am33xx_pm_remove(struct platform_device *pdev)
{
pm_runtime_put_sync(&pdev->dev);
pm_runtime_disable(&pdev->dev);
if (pm_ops->deinit)
pm_ops->deinit();
suspend_set_ops(NULL);
wkup_m3_ipc_put(m3_ipc);
am33xx_pm_free_sram();
iounmap(rtc_base_virt);
clk_put(rtc_fck);
}
static struct platform_driver am33xx_pm_driver = {
.driver = {
.name = "pm33xx",
},
.probe = am33xx_pm_probe,
.remove_new = am33xx_pm_remove,
};
module_platform_driver(am33xx_pm_driver);
MODULE_ALIAS("platform:pm33xx");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("am33xx power management driver");
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