[PATCH 07/12] bus: ti-sysc: Handle some devices in omap_device compatible way
Tony Lindgren
tony at atomide.com
Wed Feb 28 16:37:14 PST 2018
* Tony Lindgren <tony at atomide.com> [180223 21:03]:
> Now that ti-sysc can manage child devices, we must also be backwards
> compatible with the current omap_device code. With omap_device, we
> assume that the child device manages the interconnect target module
> directly.
...
> /* At this point the module is configured enough to read the revision */
> static int sysc_init_module(struct sysc *ddata)
> {
> int error;
>
> + if (ddata->cfg.quirks & (SYSC_QUIRK_NO_IDLE_ON_INIT |
> + SYSC_QUIRK_NO_RESET_ON_INIT)) {
> + ddata->revision = sysc_read_revision(ddata);
> + goto rev_quirks;
> + }
> +
> error = pm_runtime_get_sync(ddata->dev);
> if (error < 0) {
> pm_runtime_put_noidle(ddata->dev);
This needs to use only SYSC_QUIRK_NO_IDLE_ON_INIT to skip PM
runtime. Otherwise the module may not be enabled when it is
being accessed.
Updated patch below.
Regards,
Tony
8< -------------------
>From tony Mon Sep 17 00:00:00 2001
From: Tony Lindgren <tony at atomide.com>
Date: Thu, 22 Feb 2018 14:03:48 -0800
Subject: [PATCH] bus: ti-sysc: Handle some devices in omap_device
compatible way
Now that ti-sysc can manage child devices, we must also be backwards
compatible with the current omap_device code. With omap_device, we
assume that the child device manages the interconnect target module
directly.
The drivers needing special handling are the ones that still set
pm_runtime_irq_safe(). In the long run we want to update those drivers
as otherwise they will cause problems with genpd as a permanent PM
runtime usage count is set on the parent device.
We can handle omap_device these devices by improving the ti-sysc quirk
handling to detect the devices needing special handling based on
register map and revision register if usable. We also need to implement
dev_pm_domain for these child devices just like omap_device does.
Signed-off-by: Tony Lindgren <tony at atomide.com>
---
drivers/bus/ti-sysc.c | 226 +++++++++++++++++++++++++++++++++-
include/linux/platform_data/ti-sysc.h | 1 +
2 files changed, 224 insertions(+), 3 deletions(-)
diff --git a/drivers/bus/ti-sysc.c b/drivers/bus/ti-sysc.c
--- a/drivers/bus/ti-sysc.c
+++ b/drivers/bus/ti-sysc.c
@@ -14,8 +14,10 @@
#include <linux/io.h>
#include <linux/clk.h>
#include <linux/clkdev.h>
+#include <linux/delay.h>
#include <linux/module.h>
#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
#include <linux/pm_runtime.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
@@ -68,6 +70,7 @@ struct sysc {
u32 revision;
bool enabled;
bool needs_resume;
+ bool child_needs_resume;
struct delayed_work idle_work;
};
@@ -474,6 +477,14 @@ static int sysc_show_reg(struct sysc *ddata,
return sprintf(bufp, ":%x", ddata->offsets[reg]);
}
+static int sysc_show_name(char *bufp, struct sysc *ddata)
+{
+ if (!ddata->name)
+ return 0;
+
+ return sprintf(bufp, ":%s", ddata->name);
+}
+
/**
* sysc_show_registers - show information about interconnect target module
* @ddata: device driver data
@@ -488,7 +499,7 @@ static void sysc_show_registers(struct sysc *ddata)
bufp += sysc_show_reg(ddata, bufp, i);
bufp += sysc_show_rev(bufp, ddata);
- bufp += sysc_show_rev(bufp, ddata);
+ bufp += sysc_show_name(bufp, ddata);
dev_dbg(ddata->dev, "%llx:%x%s\n",
ddata->module_pa, ddata->module_size,
@@ -612,11 +623,93 @@ static const struct dev_pm_ops sysc_pm_ops = {
NULL)
};
+/* Module revision register based quirks */
+struct sysc_revision_quirk {
+ const char *name;
+ u32 base;
+ int rev_offset;
+ int sysc_offset;
+ int syss_offset;
+ u32 revision;
+ u32 revision_mask;
+ u32 quirks;
+};
+
+#define SYSC_QUIRK(optname, optbase, optrev, optsysc, optsyss, \
+ optrev_val, optrevmask, optquirkmask) \
+ { \
+ .name = (optname), \
+ .base = (optbase), \
+ .rev_offset = (optrev), \
+ .sysc_offset = (optsysc), \
+ .syss_offset = (optsyss), \
+ .revision = (optrev_val), \
+ .revision_mask = (optrevmask), \
+ .quirks = (optquirkmask), \
+ }
+
+static const struct sysc_revision_quirk sysc_revision_quirks[] = {
+ /* These drivers need to be fixed to not use pm_runtime_irq_safe() */
+ SYSC_QUIRK("gpio", 0, 0, 0x10, 0x114, 0x50600801, 0xffffffff,
+ SYSC_QUIRK_LEGACY_IDLE),
+ SYSC_QUIRK("mmu", 0, 0, 0x10, 0x14, 0x00000020, 0xffffffff,
+ SYSC_QUIRK_LEGACY_IDLE),
+ SYSC_QUIRK("mmu", 0, 0, 0x10, 0x14, 0x00000030, 0xffffffff,
+ SYSC_QUIRK_LEGACY_IDLE),
+ SYSC_QUIRK("sham", 0, 0x100, 0x110, 0x114, 0x40000c03, 0xffffffff,
+ SYSC_QUIRK_LEGACY_IDLE),
+ SYSC_QUIRK("smartreflex", 0, -1, 0x24, -1, 0x00000000, 0xffffffff,
+ SYSC_QUIRK_LEGACY_IDLE),
+ SYSC_QUIRK("smartreflex", 0, -1, 0x38, -1, 0x00000000, 0xffffffff,
+ SYSC_QUIRK_LEGACY_IDLE),
+ SYSC_QUIRK("timer", 0, 0, 0x10, 0x14, 0x00000015, 0xffffffff,
+ SYSC_QUIRK_LEGACY_IDLE),
+ SYSC_QUIRK("uart", 0, 0x50, 0x54, 0x58, 0x00000052, 0xffffffff,
+ SYSC_QUIRK_LEGACY_IDLE),
+};
+
+static void sysc_init_revision_quirks(struct sysc *ddata)
+{
+ const struct sysc_revision_quirk *q;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(sysc_revision_quirks); i++) {
+ q = &sysc_revision_quirks[i];
+
+ if (q->base && q->base != ddata->module_pa)
+ continue;
+
+ if (q->rev_offset >= 0 &&
+ q->rev_offset != ddata->offsets[SYSC_REVISION])
+ continue;
+
+ if (q->sysc_offset >= 0 &&
+ q->sysc_offset != ddata->offsets[SYSC_SYSCONFIG])
+ continue;
+
+ if (q->syss_offset >= 0 &&
+ q->syss_offset != ddata->offsets[SYSC_SYSSTATUS])
+ continue;
+
+ if (q->revision == ddata->revision ||
+ (q->revision & q->revision_mask) ==
+ (ddata->revision & q->revision_mask)) {
+ ddata->name = q->name;
+ ddata->cfg.quirks |= q->quirks;
+ }
+ }
+}
+
/* At this point the module is configured enough to read the revision */
static int sysc_init_module(struct sysc *ddata)
{
int error;
+ if (ddata->cfg.quirks & SYSC_QUIRK_NO_IDLE_ON_INIT) {
+ ddata->revision = sysc_read_revision(ddata);
+ goto rev_quirks;
+ }
+
error = pm_runtime_get_sync(ddata->dev);
if (error < 0) {
pm_runtime_put_noidle(ddata->dev);
@@ -626,6 +719,9 @@ static int sysc_init_module(struct sysc *ddata)
ddata->revision = sysc_read_revision(ddata);
pm_runtime_put_sync(ddata->dev);
+rev_quirks:
+ sysc_init_revision_quirks(ddata);
+
return 0;
}
@@ -753,6 +849,127 @@ static struct sysc *sysc_child_to_parent(struct device *dev)
return dev_get_drvdata(parent);
}
+static int __maybe_unused sysc_child_runtime_suspend(struct device *dev)
+{
+ struct sysc *ddata;
+ int error;
+
+ ddata = sysc_child_to_parent(dev);
+
+ error = pm_generic_runtime_suspend(dev);
+ if (error)
+ return error;
+
+ if (!ddata->enabled)
+ return 0;
+
+ return sysc_runtime_suspend(ddata->dev);
+}
+
+static int __maybe_unused sysc_child_runtime_resume(struct device *dev)
+{
+ struct sysc *ddata;
+ int error;
+
+ ddata = sysc_child_to_parent(dev);
+
+ if (!ddata->enabled) {
+ error = sysc_runtime_resume(ddata->dev);
+ if (error < 0)
+ dev_err(ddata->dev,
+ "%s error: %i\n", __func__, error);
+ }
+
+ return pm_generic_runtime_resume(dev);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int sysc_child_suspend_noirq(struct device *dev)
+{
+ struct sysc *ddata;
+ int error;
+
+ ddata = sysc_child_to_parent(dev);
+
+ error = pm_generic_suspend_noirq(dev);
+ if (error)
+ return error;
+
+ if (!pm_runtime_status_suspended(dev)) {
+ error = pm_generic_runtime_suspend(dev);
+ if (error)
+ return error;
+
+ error = sysc_runtime_suspend(ddata->dev);
+ if (error)
+ return error;
+
+ ddata->child_needs_resume = true;
+ }
+
+ return 0;
+}
+
+static int sysc_child_resume_noirq(struct device *dev)
+{
+ struct sysc *ddata;
+ int error;
+
+ ddata = sysc_child_to_parent(dev);
+
+ if (ddata->child_needs_resume) {
+ ddata->child_needs_resume = false;
+
+ error = sysc_runtime_resume(ddata->dev);
+ if (error)
+ dev_err(ddata->dev,
+ "%s runtime resume error: %i\n",
+ __func__, error);
+
+ error = pm_generic_runtime_resume(dev);
+ if (error)
+ dev_err(ddata->dev,
+ "%s generic runtime resume: %i\n",
+ __func__, error);
+ }
+
+ return pm_generic_resume_noirq(dev);
+}
+#endif
+
+struct dev_pm_domain sysc_child_pm_domain = {
+ .ops = {
+ SET_RUNTIME_PM_OPS(sysc_child_runtime_suspend,
+ sysc_child_runtime_resume,
+ NULL)
+ USE_PLATFORM_PM_SLEEP_OPS
+ SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(sysc_child_suspend_noirq,
+ sysc_child_resume_noirq)
+ }
+};
+
+/**
+ * sysc_legacy_idle_quirk - handle children in omap_device compatible way
+ * @ddata: device driver data
+ * @child: child device driver
+ *
+ * Allow idle for child devices as done with _od_runtime_suspend().
+ * Otherwise many child devices will not idle because of the permanent
+ * parent usecount set in pm_runtime_irq_safe().
+ *
+ * Note that the long term solution is to just modify the child device
+ * drivers to not set pm_runtime_irq_safe() and then this can be just
+ * dropped.
+ */
+static void sysc_legacy_idle_quirk(struct sysc *ddata, struct device *child)
+{
+ if (!ddata->legacy_mode)
+ return;
+
+ if (ddata->cfg.quirks & SYSC_QUIRK_LEGACY_IDLE)
+ dev_pm_domain_set(child, &sysc_child_pm_domain);
+}
+
static int sysc_notifier_call(struct notifier_block *nb,
unsigned long event, void *device)
{
@@ -770,6 +987,7 @@ static int sysc_notifier_call(struct notifier_block *nb,
if (error && error != -EEXIST)
dev_warn(ddata->dev, "could not add %s fck: %i\n",
dev_name(dev), error);
+ sysc_legacy_idle_quirk(ddata, dev);
break;
default:
break;
@@ -974,7 +1192,8 @@ static const struct sysc_capabilities sysc_34xx_sr = {
.type = TI_SYSC_OMAP34XX_SR,
.sysc_mask = SYSC_OMAP2_CLOCKACTIVITY,
.regbits = &sysc_regbits_omap34xx_sr,
- .mod_quirks = SYSC_QUIRK_USE_CLOCKACT | SYSC_QUIRK_UNCACHED,
+ .mod_quirks = SYSC_QUIRK_USE_CLOCKACT | SYSC_QUIRK_UNCACHED |
+ SYSC_QUIRK_LEGACY_IDLE,
};
/*
@@ -995,12 +1214,13 @@ static const struct sysc_capabilities sysc_36xx_sr = {
.type = TI_SYSC_OMAP36XX_SR,
.sysc_mask = SYSC_OMAP3_SR_ENAWAKEUP,
.regbits = &sysc_regbits_omap36xx_sr,
- .mod_quirks = SYSC_QUIRK_UNCACHED,
+ .mod_quirks = SYSC_QUIRK_UNCACHED | SYSC_QUIRK_LEGACY_IDLE,
};
static const struct sysc_capabilities sysc_omap4_sr = {
.type = TI_SYSC_OMAP4_SR,
.regbits = &sysc_regbits_omap36xx_sr,
+ .mod_quirks = SYSC_QUIRK_LEGACY_IDLE,
};
/*
diff --git a/include/linux/platform_data/ti-sysc.h b/include/linux/platform_data/ti-sysc.h
--- a/include/linux/platform_data/ti-sysc.h
+++ b/include/linux/platform_data/ti-sysc.h
@@ -45,6 +45,7 @@ struct sysc_regbits {
s8 emufree_shift;
};
+#define SYSC_QUIRK_LEGACY_IDLE BIT(8)
#define SYSC_QUIRK_RESET_STATUS BIT(7)
#define SYSC_QUIRK_NO_IDLE_ON_INIT BIT(6)
#define SYSC_QUIRK_NO_RESET_ON_INIT BIT(5)
--
2.16.2
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