diff mbox series

[v2,1/2] regmap: Add hardware spinlock support

Message ID 00b91de822135699da81f70c4d2b8fecbc113ab1.1509501110.git.baolin.wang@linaro.org
State New
Headers show
Series [v2,1/2] regmap: Add hardware spinlock support | expand

Commit Message

(Exiting) Baolin Wang Nov. 1, 2017, 2:11 a.m. UTC 
On some platforms, when reading or writing some special registers through
regmap, we should acquire one hardware spinlock to synchronize between
the multiple subsystems. Thus this patch adds the hardware spinlock
support for regmap.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>

---
Changes since v1:
 - Move hwspinlock.h including to regmap.c file.
 - Remove hwspin_trylock_xxx() functions.
 - We always set the timeout as maximum values to avoid getting lock failed.
 - Coding style fixes.
---
 drivers/base/regmap/internal.h |    2 +
 drivers/base/regmap/regmap.c   |  101 +++++++++++++++++++++++++++++++++-------
 include/linux/regmap.h         |    6 +++
 3 files changed, 93 insertions(+), 16 deletions(-)

-- 
1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Comments

Mark Brown Nov. 1, 2017, 10:13 a.m. UTC | #1 
On Wed, Nov 01, 2017 at 10:11:55AM +0800, Baolin Wang wrote:
> On some platforms, when reading or writing some special registers through

> regmap, we should acquire one hardware spinlock to synchronize between

> the multiple subsystems. Thus this patch adds the hardware spinlock

> support for regmap.


The following changes since commit 2bd6bf03f4c1c59381d62c61d03f6cc3fe71f66e:

  Linux 4.14-rc1 (2017-09-16 15:47:51 -0700)

are available in the Git repository at:

  https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap.git tags/regmap-hwspinlock-support

for you to fetch changes up to 8698b9364710e7bac84b3af07dd410e39c8c2e08:

  regmap: Add hardware spinlock support (2017-11-01 10:06:29 +0000)

----------------------------------------------------------------
regmap: Add hwspinlock support

----------------------------------------------------------------
Baolin Wang (1):
      regmap: Add hardware spinlock support

 drivers/base/regmap/internal.h |   2 +
 drivers/base/regmap/regmap.c   | 101 ++++++++++++++++++++++++++++++++++-------
 include/linux/regmap.h         |   6 +++
 3 files changed, 93 insertions(+), 16 deletions(-)
Rob Herring (Arm) Nov. 2, 2017, 12:12 a.m. UTC | #2 
On Wed, Nov 01, 2017 at 10:11:56AM +0800, Baolin Wang wrote:
> Some system control registers need hardware spinlock to synchronize

> between the multiple subsystems, so we should add hardware spinlock

> support for syscon.

> 

> Signed-off-by: Baolin Wang <baolin.wang@linaro.org>

> ---

> Changes since v1:

>  - Remove timeout configuration.

>  - Modify the binding file to add hwlocks.

> ---

>  Documentation/devicetree/bindings/mfd/syscon.txt |    1 +

>  drivers/mfd/syscon.c                             |    7 +++++++

>  2 files changed, 8 insertions(+)


Acked-by: Rob Herring <robh@kernel.org>

--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox series

Patch

diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h
index 2a4435d..8641183 100644
--- a/drivers/base/regmap/internal.h
+++ b/drivers/base/regmap/internal.h
@@ -157,6 +157,8 @@  struct regmap {
 
 	struct rb_root range_tree;
 	void *selector_work_buf;	/* Scratch buffer used for selector */
+
+	struct hwspinlock *hwlock;
 };
 
 struct regcache_ops {
diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index b9a779a..999e981 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -20,6 +20,7 @@ 
 #include <linux/sched.h>
 #include <linux/delay.h>
 #include <linux/log2.h>
+#include <linux/hwspinlock.h>
 
 #define CREATE_TRACE_POINTS
 #include "trace.h"
@@ -413,6 +414,49 @@  static unsigned int regmap_parse_64_native(const void *buf)
 }
 #endif
 
+static void regmap_lock_hwlock(void *__map)
+{
+	struct regmap *map = __map;
+
+	hwspin_lock_timeout(map->hwlock, UINT_MAX);
+}
+
+static void regmap_lock_hwlock_irq(void *__map)
+{
+	struct regmap *map = __map;
+
+	hwspin_lock_timeout_irq(map->hwlock, UINT_MAX);
+}
+
+static void regmap_lock_hwlock_irqsave(void *__map)
+{
+	struct regmap *map = __map;
+
+	hwspin_lock_timeout_irqsave(map->hwlock, UINT_MAX,
+				    &map->spinlock_flags);
+}
+
+static void regmap_unlock_hwlock(void *__map)
+{
+	struct regmap *map = __map;
+
+	hwspin_unlock(map->hwlock);
+}
+
+static void regmap_unlock_hwlock_irq(void *__map)
+{
+	struct regmap *map = __map;
+
+	hwspin_unlock_irq(map->hwlock);
+}
+
+static void regmap_unlock_hwlock_irqrestore(void *__map)
+{
+	struct regmap *map = __map;
+
+	hwspin_unlock_irqrestore(map->hwlock, &map->spinlock_flags);
+}
+
 static void regmap_lock_mutex(void *__map)
 {
 	struct regmap *map = __map;
@@ -627,6 +671,29 @@  struct regmap *__regmap_init(struct device *dev,
 		map->lock = config->lock;
 		map->unlock = config->unlock;
 		map->lock_arg = config->lock_arg;
+	} else if (config->hwlock_id) {
+		map->hwlock = hwspin_lock_request_specific(config->hwlock_id);
+		if (!map->hwlock) {
+			ret = -ENXIO;
+			goto err_map;
+		}
+
+		switch (config->hwlock_mode) {
+		case HWLOCK_IRQSTATE:
+			map->lock = regmap_lock_hwlock_irqsave;
+			map->unlock = regmap_unlock_hwlock_irqrestore;
+			break;
+		case HWLOCK_IRQ:
+			map->lock = regmap_lock_hwlock_irq;
+			map->unlock = regmap_unlock_hwlock_irq;
+			break;
+		default:
+			map->lock = regmap_lock_hwlock;
+			map->unlock = regmap_unlock_hwlock;
+			break;
+		}
+
+		map->lock_arg = map;
 	} else {
 		if ((bus && bus->fast_io) ||
 		    config->fast_io) {
@@ -729,7 +796,7 @@  struct regmap *__regmap_init(struct device *dev,
 			map->format.format_write = regmap_format_2_6_write;
 			break;
 		default:
-			goto err_map;
+			goto err_hwlock;
 		}
 		break;
 
@@ -739,7 +806,7 @@  struct regmap *__regmap_init(struct device *dev,
 			map->format.format_write = regmap_format_4_12_write;
 			break;
 		default:
-			goto err_map;
+			goto err_hwlock;
 		}
 		break;
 
@@ -749,7 +816,7 @@  struct regmap *__regmap_init(struct device *dev,
 			map->format.format_write = regmap_format_7_9_write;
 			break;
 		default:
-			goto err_map;
+			goto err_hwlock;
 		}
 		break;
 
@@ -759,7 +826,7 @@  struct regmap *__regmap_init(struct device *dev,
 			map->format.format_write = regmap_format_10_14_write;
 			break;
 		default:
-			goto err_map;
+			goto err_hwlock;
 		}
 		break;
 
@@ -779,13 +846,13 @@  struct regmap *__regmap_init(struct device *dev,
 			map->format.format_reg = regmap_format_16_native;
 			break;
 		default:
-			goto err_map;
+			goto err_hwlock;
 		}
 		break;
 
 	case 24:
 		if (reg_endian != REGMAP_ENDIAN_BIG)
-			goto err_map;
+			goto err_hwlock;
 		map->format.format_reg = regmap_format_24;
 		break;
 
@@ -801,7 +868,7 @@  struct regmap *__regmap_init(struct device *dev,
 			map->format.format_reg = regmap_format_32_native;
 			break;
 		default:
-			goto err_map;
+			goto err_hwlock;
 		}
 		break;
 
@@ -818,13 +885,13 @@  struct regmap *__regmap_init(struct device *dev,
 			map->format.format_reg = regmap_format_64_native;
 			break;
 		default:
-			goto err_map;
+			goto err_hwlock;
 		}
 		break;
 #endif
 
 	default:
-		goto err_map;
+		goto err_hwlock;
 	}
 
 	if (val_endian == REGMAP_ENDIAN_NATIVE)
@@ -853,12 +920,12 @@  struct regmap *__regmap_init(struct device *dev,
 			map->format.parse_val = regmap_parse_16_native;
 			break;
 		default:
-			goto err_map;
+			goto err_hwlock;
 		}
 		break;
 	case 24:
 		if (val_endian != REGMAP_ENDIAN_BIG)
-			goto err_map;
+			goto err_hwlock;
 		map->format.format_val = regmap_format_24;
 		map->format.parse_val = regmap_parse_24;
 		break;
@@ -879,7 +946,7 @@  struct regmap *__regmap_init(struct device *dev,
 			map->format.parse_val = regmap_parse_32_native;
 			break;
 		default:
-			goto err_map;
+			goto err_hwlock;
 		}
 		break;
 #ifdef CONFIG_64BIT
@@ -900,7 +967,7 @@  struct regmap *__regmap_init(struct device *dev,
 			map->format.parse_val = regmap_parse_64_native;
 			break;
 		default:
-			goto err_map;
+			goto err_hwlock;
 		}
 		break;
 #endif
@@ -909,18 +976,18 @@  struct regmap *__regmap_init(struct device *dev,
 	if (map->format.format_write) {
 		if ((reg_endian != REGMAP_ENDIAN_BIG) ||
 		    (val_endian != REGMAP_ENDIAN_BIG))
-			goto err_map;
+			goto err_hwlock;
 		map->use_single_write = true;
 	}
 
 	if (!map->format.format_write &&
 	    !(map->format.format_reg && map->format.format_val))
-		goto err_map;
+		goto err_hwlock;
 
 	map->work_buf = kzalloc(map->format.buf_size, GFP_KERNEL);
 	if (map->work_buf == NULL) {
 		ret = -ENOMEM;
-		goto err_map;
+		goto err_hwlock;
 	}
 
 	if (map->format.format_write) {
@@ -1041,6 +1108,8 @@  struct regmap *__regmap_init(struct device *dev,
 err_range:
 	regmap_range_exit(map);
 	kfree(map->work_buf);
+err_hwlock:
+	hwspin_lock_free(map->hwlock);
 err_map:
 	kfree(map);
 err:
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index 978abfb..edc32aa 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -273,6 +273,9 @@  struct regmap_access_table {
  *
  * @ranges: Array of configuration entries for virtual address ranges.
  * @num_ranges: Number of range configuration entries.
+ * @hwlock_id: Specify the hardware spinlock id.
+ * @hwlock_mode: The hardware spinlock mode, should be HWLOCK_IRQSTATE,
+ *		 HWLOCK_IRQ or 0.
  */
 struct regmap_config {
 	const char *name;
@@ -317,6 +320,9 @@  struct regmap_config {
 
 	const struct regmap_range_cfg *ranges;
 	unsigned int num_ranges;
+
+	unsigned int hwlock_id;
+	unsigned int hwlock_mode;
 };
 
 /**