drivers: move the early platform device support to arch/sh

SuperH is the only user of the current implementation of early platform
device support. We want to introduce a more robust approach to early
probing. As the first step - move all the current early platform code
to arch/sh.

In order not to export internal drivers/base functions to arch code for
this temporary solution - copy the two needed routines for driver
matching from drivers/base/platform.c to arch/sh/drivers/platform_early.c.

Also: call early_platform_cleanup() from subsys_initcall() so that it's
called after all early devices are probed.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Rich Felker <dalias@libc.org>
Link: https://lore.kernel.org/r/20191003092913.10731-2-brgl@bgdev.pl
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

5 files changed, 28 insertions, 289 deletions

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index b6c6c7d97d5b..be1e67ee3af6 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -1264,8 +1264,6 @@ int __init platform_bus_init(void)
 {
 	int error;
 
-	early_platform_cleanup();
-
 	error = device_register(&platform_bus);
 	if (error) {
 		put_device(&platform_bus);
@@ -1277,289 +1275,3 @@ int __init platform_bus_init(void)
 	of_platform_register_reconfig_notifier();
 	return error;
 }
-
-static __initdata LIST_HEAD(early_platform_driver_list);
-static __initdata LIST_HEAD(early_platform_device_list);
-
-/**
- * early_platform_driver_register - register early platform driver
- * @epdrv: early_platform driver structure
- * @buf: string passed from early_param()
- *
- * Helper function for early_platform_init() / early_platform_init_buffer()
- */
-int __init early_platform_driver_register(struct early_platform_driver *epdrv,
-					  char *buf)
-{
-	char *tmp;
-	int n;
-
-	/* Simply add the driver to the end of the global list.
-	 * Drivers will by default be put on the list in compiled-in order.
-	 */
-	if (!epdrv->list.next) {
-		INIT_LIST_HEAD(&epdrv->list);
-		list_add_tail(&epdrv->list, &early_platform_driver_list);
-	}
-
-	/* If the user has specified device then make sure the driver
-	 * gets prioritized. The driver of the last device specified on
-	 * command line will be put first on the list.
-	 */
-	n = strlen(epdrv->pdrv->driver.name);
-	if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
-		list_move(&epdrv->list, &early_platform_driver_list);
-
-		/* Allow passing parameters after device name */
-		if (buf[n] == '\0' || buf[n] == ',')
-			epdrv->requested_id = -1;
-		else {
-			epdrv->requested_id = simple_strtoul(&buf[n + 1],
-							     &tmp, 10);
-
-			if (buf[n] != '.' || (tmp == &buf[n + 1])) {
-				epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
-				n = 0;
-			} else
-				n += strcspn(&buf[n + 1], ",") + 1;
-		}
-
-		if (buf[n] == ',')
-			n++;
-
-		if (epdrv->bufsize) {
-			memcpy(epdrv->buffer, &buf[n],
-			       min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
-			epdrv->buffer[epdrv->bufsize - 1] = '\0';
-		}
-	}
-
-	return 0;
-}
-
-/**
- * early_platform_add_devices - adds a number of early platform devices
- * @devs: array of early platform devices to add
- * @num: number of early platform devices in array
- *
- * Used by early architecture code to register early platform devices and
- * their platform data.
- */
-void __init early_platform_add_devices(struct platform_device **devs, int num)
-{
-	struct device *dev;
-	int i;
-
-	/* simply add the devices to list */
-	for (i = 0; i < num; i++) {
-		dev = &devs[i]->dev;
-
-		if (!dev->devres_head.next) {
-			pm_runtime_early_init(dev);
-			INIT_LIST_HEAD(&dev->devres_head);
-			list_add_tail(&dev->devres_head,
-				      &early_platform_device_list);
-		}
-	}
-}
-
-/**
- * early_platform_driver_register_all - register early platform drivers
- * @class_str: string to identify early platform driver class
- *
- * Used by architecture code to register all early platform drivers
- * for a certain class. If omitted then only early platform drivers
- * with matching kernel command line class parameters will be registered.
- */
-void __init early_platform_driver_register_all(char *class_str)
-{
-	/* The "class_str" parameter may or may not be present on the kernel
-	 * command line. If it is present then there may be more than one
-	 * matching parameter.
-	 *
-	 * Since we register our early platform drivers using early_param()
-	 * we need to make sure that they also get registered in the case
-	 * when the parameter is missing from the kernel command line.
-	 *
-	 * We use parse_early_options() to make sure the early_param() gets
-	 * called at least once. The early_param() may be called more than
-	 * once since the name of the preferred device may be specified on
-	 * the kernel command line. early_platform_driver_register() handles
-	 * this case for us.
-	 */
-	parse_early_options(class_str);
-}
-
-/**
- * early_platform_match - find early platform device matching driver
- * @epdrv: early platform driver structure
- * @id: id to match against
- */
-static struct platform_device * __init
-early_platform_match(struct early_platform_driver *epdrv, int id)
-{
-	struct platform_device *pd;
-
-	list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
-		if (platform_match(&pd->dev, &epdrv->pdrv->driver))
-			if (pd->id == id)
-				return pd;
-
-	return NULL;
-}
-
-/**
- * early_platform_left - check if early platform driver has matching devices
- * @epdrv: early platform driver structure
- * @id: return true if id or above exists
- */
-static int __init early_platform_left(struct early_platform_driver *epdrv,
-				       int id)
-{
-	struct platform_device *pd;
-
-	list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
-		if (platform_match(&pd->dev, &epdrv->pdrv->driver))
-			if (pd->id >= id)
-				return 1;
-
-	return 0;
-}
-
-/**
- * early_platform_driver_probe_id - probe drivers matching class_str and id
- * @class_str: string to identify early platform driver class
- * @id: id to match against
- * @nr_probe: number of platform devices to successfully probe before exiting
- */
-static int __init early_platform_driver_probe_id(char *class_str,
-						 int id,
-						 int nr_probe)
-{
-	struct early_platform_driver *epdrv;
-	struct platform_device *match;
-	int match_id;
-	int n = 0;
-	int left = 0;
-
-	list_for_each_entry(epdrv, &early_platform_driver_list, list) {
-		/* only use drivers matching our class_str */
-		if (strcmp(class_str, epdrv->class_str))
-			continue;
-
-		if (id == -2) {
-			match_id = epdrv->requested_id;
-			left = 1;
-
-		} else {
-			match_id = id;
-			left += early_platform_left(epdrv, id);
-
-			/* skip requested id */
-			switch (epdrv->requested_id) {
-			case EARLY_PLATFORM_ID_ERROR:
-			case EARLY_PLATFORM_ID_UNSET:
-				break;
-			default:
-				if (epdrv->requested_id == id)
-					match_id = EARLY_PLATFORM_ID_UNSET;
-			}
-		}
-
-		switch (match_id) {
-		case EARLY_PLATFORM_ID_ERROR:
-			pr_warn("%s: unable to parse %s parameter\n",
-				class_str, epdrv->pdrv->driver.name);
-			/* fall-through */
-		case EARLY_PLATFORM_ID_UNSET:
-			match = NULL;
-			break;
-		default:
-			match = early_platform_match(epdrv, match_id);
-		}
-
-		if (match) {
-			/*
-			 * Set up a sensible init_name to enable
-			 * dev_name() and others to be used before the
-			 * rest of the driver core is initialized.
-			 */
-			if (!match->dev.init_name && slab_is_available()) {
-				if (match->id != -1)
-					match->dev.init_name =
-						kasprintf(GFP_KERNEL, "%s.%d",
-							  match->name,
-							  match->id);
-				else
-					match->dev.init_name =
-						kasprintf(GFP_KERNEL, "%s",
-							  match->name);
-
-				if (!match->dev.init_name)
-					return -ENOMEM;
-			}
-
-			if (epdrv->pdrv->probe(match))
-				pr_warn("%s: unable to probe %s early.\n",
-					class_str, match->name);
-			else
-				n++;
-		}
-
-		if (n >= nr_probe)
-			break;
-	}
-
-	if (left)
-		return n;
-	else
-		return -ENODEV;
-}
-
-/**
- * early_platform_driver_probe - probe a class of registered drivers
- * @class_str: string to identify early platform driver class
- * @nr_probe: number of platform devices to successfully probe before exiting
- * @user_only: only probe user specified early platform devices
- *
- * Used by architecture code to probe registered early platform drivers
- * within a certain class. For probe to happen a registered early platform
- * device matching a registered early platform driver is needed.
- */
-int __init early_platform_driver_probe(char *class_str,
-				       int nr_probe,
-				       int user_only)
-{
-	int k, n, i;
-
-	n = 0;
-	for (i = -2; n < nr_probe; i++) {
-		k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
-
-		if (k < 0)
-			break;
-
-		n += k;
-
-		if (user_only)
-			break;
-	}
-
-	return n;
-}
-
-/**
- * early_platform_cleanup - clean up early platform code
- */
-void __init early_platform_cleanup(void)
-{
-	struct platform_device *pd, *pd2;
-
-	/* clean up the devres list used to chain devices */
-	list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
-				 dev.devres_head) {
-		list_del(&pd->dev.devres_head);
-		memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));
-	}
-}
-
diff --git a/drivers/clocksource/sh_cmt.c b/drivers/clocksource/sh_cmt.c
index ef773db080e9..3a185485300e 100644
--- a/drivers/clocksource/sh_cmt.c
+++ b/drivers/clocksource/sh_cmt.c
@@ -25,6 +25,10 @@
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 
+#ifdef CONFIG_SUPERH
+#include <asm/platform_early.h>
+#endif
+
 struct sh_cmt_device;
 
 /*
@@ -1109,7 +1113,10 @@ static void __exit sh_cmt_exit(void)
 	platform_driver_unregister(&sh_cmt_device_driver);
 }
 
+#ifdef CONFIG_SUPERH
 early_platform_init("earlytimer", &sh_cmt_device_driver);
+#endif
+
 subsys_initcall(sh_cmt_init);
 module_exit(sh_cmt_exit);
 
diff --git a/drivers/clocksource/sh_mtu2.c b/drivers/clocksource/sh_mtu2.c
index 354b27d14a19..d581060d33a2 100644
--- a/drivers/clocksource/sh_mtu2.c
+++ b/drivers/clocksource/sh_mtu2.c
@@ -23,6 +23,10 @@
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 
+#ifdef CONFIG_SUPERH
+#include <asm/platform_early.h>
+#endif
+
 struct sh_mtu2_device;
 
 struct sh_mtu2_channel {
@@ -511,7 +515,10 @@ static void __exit sh_mtu2_exit(void)
 	platform_driver_unregister(&sh_mtu2_device_driver);
 }
 
+#ifdef CONFIG_SUPERH
 early_platform_init("earlytimer", &sh_mtu2_device_driver);
+#endif
+
 subsys_initcall(sh_mtu2_init);
 module_exit(sh_mtu2_exit);
 
diff --git a/drivers/clocksource/sh_tmu.c b/drivers/clocksource/sh_tmu.c
index 8c4f3753b36e..50e30ead050e 100644
--- a/drivers/clocksource/sh_tmu.c
+++ b/drivers/clocksource/sh_tmu.c
@@ -24,6 +24,10 @@
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 
+#ifdef CONFIG_SUPERH
+#include <asm/platform_early.h>
+#endif
+
 enum sh_tmu_model {
 	SH_TMU,
 	SH_TMU_SH3,
@@ -615,6 +619,7 @@ static int sh_tmu_probe(struct platform_device *pdev)
 		pm_runtime_idle(&pdev->dev);
 		return ret;
 	}
+
 	if (is_early_platform_device(pdev))
 		return 0;
 
@@ -665,7 +670,10 @@ static void __exit sh_tmu_exit(void)
 	platform_driver_unregister(&sh_tmu_device_driver);
 }
 
+#ifdef CONFIG_SUPERH
 early_platform_init("earlytimer", &sh_tmu_device_driver);
+#endif
+
 subsys_initcall(sh_tmu_init);
 module_exit(sh_tmu_exit);
 
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 4e754a4850e6..2a645fd7f07b 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -54,6 +54,7 @@
 
 #ifdef CONFIG_SUPERH
 #include <asm/sh_bios.h>
+#include <asm/platform_early.h>
 #endif
 
 #include "serial_mctrl_gpio.h"
@@ -3086,6 +3087,7 @@ static struct console serial_console = {
 	.data		= &sci_uart_driver,
 };
 
+#ifdef CONFIG_SUPERH
 static struct console early_serial_console = {
 	.name           = "early_ttySC",
 	.write          = serial_console_write,
@@ -3114,6 +3116,7 @@ static int sci_probe_earlyprintk(struct platform_device *pdev)
 	register_console(&early_serial_console);
 	return 0;
 }
+#endif
 
 #define SCI_CONSOLE	(&serial_console)
 
@@ -3314,8 +3317,10 @@ static int sci_probe(struct platform_device *dev)
 	 * the special early probe. We don't have sufficient device state
 	 * to make it beyond this yet.
 	 */
+#ifdef CONFIG_SUPERH
 	if (is_early_platform_device(dev))
 		return sci_probe_earlyprintk(dev);
+#endif
 
 	if (dev->dev.of_node) {
 		p = sci_parse_dt(dev, &dev_id);
@@ -3410,7 +3415,7 @@ static void __exit sci_exit(void)
 		uart_unregister_driver(&sci_uart_driver);
 }
 
-#ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
+#if defined(CONFIG_SUPERH) && defined(CONFIG_SERIAL_SH_SCI_CONSOLE)
 early_platform_init_buffer("earlyprintk", &sci_driver,
 			   early_serial_buf, ARRAY_SIZE(early_serial_buf));
 #endif