[PATCH 1/3] firmware: arm_scpi: improve struct dvfs_info to make code better readable

[PATCH 1/3] firmware: arm_scpi: improve struct dvfs_info to make code better readable

[Heiner Kallweit]

Making the header subfields members of struct dvfs_info allows to make
the code better readable and avoids some macro magic.

In addition remove a useless statement using info->latency.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 drivers/firmware/arm_scpi.c | 13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/drivers/firmware/arm_scpi.c b/drivers/firmware/arm_scpi.c
index f713a64c..412f1c4c 100644
--- a/drivers/firmware/arm_scpi.c
+++ b/drivers/firmware/arm_scpi.c
@@ -72,8 +72,6 @@
 
 #define MAX_DVFS_DOMAINS	8
 #define MAX_DVFS_OPPS		16
-#define DVFS_LATENCY(hdr)	(le32_to_cpu(hdr) >> 16)
-#define DVFS_OPP_COUNT(hdr)	((le32_to_cpu(hdr) >> 8) & 0xff)
 
 #define PROTOCOL_REV_MINOR_BITS	16
 #define PROTOCOL_REV_MINOR_MASK	((1U << PROTOCOL_REV_MINOR_BITS) - 1)
@@ -328,7 +326,9 @@ struct legacy_clk_set_value {
 } __packed;
 
 struct dvfs_info {
-	__le32 header;
+	u8 domain;
+	u8 opp_count;
+	__le16 latency;
 	struct {
 		__le32 freq;
 		__le32 m_volt;
@@ -667,8 +667,8 @@ static int scpi_dvfs_populate_info(struct device *dev, u8 domain)
 	if (!info)
 		return -ENOMEM;
 
-	info->count = DVFS_OPP_COUNT(buf.header);
-	info->latency = DVFS_LATENCY(buf.header) * 1000; /* uS to nS */
+	info->count = buf.opp_count;
+	info->latency = le16_to_cpu(buf.latency) * 1000; /* uS to nS */
 
 	info->opps = devm_kcalloc(dev, info->count, sizeof(*opp), GFP_KERNEL);
 	if (!info->opps)
@@ -721,9 +721,6 @@ static int scpi_dvfs_get_transition_latency(struct device *dev)
 	if (IS_ERR(info))
 		return PTR_ERR(info);
 
-	if (!info->latency)
-		return 0;
-
 	return info->latency;
 }
 
-- 
2.14.2

[PATCH 2/3] firmware: arm_scpi: improve handling of protocol and firmware version subfields

[Heiner Kallweit]

By using FIELD_GET and proper masks we can avoid quite some shifting
and masking macro magic and make the code better readable.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 drivers/firmware/arm_scpi.c | 43 +++++++++++++++++++------------------------
 1 file changed, 19 insertions(+), 24 deletions(-)

diff --git a/drivers/firmware/arm_scpi.c b/drivers/firmware/arm_scpi.c
index 412f1c4c..d305b926 100644
--- a/drivers/firmware/arm_scpi.c
+++ b/drivers/firmware/arm_scpi.c
@@ -28,6 +28,7 @@
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/bitmap.h>
+#include <linux/bitfield.h>
 #include <linux/device.h>
 #include <linux/err.h>
 #include <linux/export.h>
@@ -73,18 +74,12 @@
 #define MAX_DVFS_DOMAINS	8
 #define MAX_DVFS_OPPS		16
 
-#define PROTOCOL_REV_MINOR_BITS	16
-#define PROTOCOL_REV_MINOR_MASK	((1U << PROTOCOL_REV_MINOR_BITS) - 1)
-#define PROTOCOL_REV_MAJOR(x)	((x) >> PROTOCOL_REV_MINOR_BITS)
-#define PROTOCOL_REV_MINOR(x)	((x) & PROTOCOL_REV_MINOR_MASK)
+#define PROTO_REV_MAJOR_MASK	GENMASK(31, 16)
+#define PROTO_REV_MINOR_MASK	GENMASK(15, 0)
 
-#define FW_REV_MAJOR_BITS	24
-#define FW_REV_MINOR_BITS	16
-#define FW_REV_PATCH_MASK	((1U << FW_REV_MINOR_BITS) - 1)
-#define FW_REV_MINOR_MASK	((1U << FW_REV_MAJOR_BITS) - 1)
-#define FW_REV_MAJOR(x)		((x) >> FW_REV_MAJOR_BITS)
-#define FW_REV_MINOR(x)		(((x) & FW_REV_MINOR_MASK) >> FW_REV_MINOR_BITS)
-#define FW_REV_PATCH(x)		((x) & FW_REV_PATCH_MASK)
+#define FW_REV_MAJOR_MASK	GENMASK(31, 24)
+#define FW_REV_MINOR_MASK	GENMASK(23, 16)
+#define FW_REV_PATCH_MASK	GENMASK(15, 0)
 
 #define MAX_RX_TIMEOUT		(msecs_to_jiffies(30))
 
@@ -867,19 +862,19 @@ static int scpi_init_versions(struct scpi_drvinfo *info)
 static ssize_t protocol_version_show(struct device *dev,
 				     struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%d.%d\n",
-		       PROTOCOL_REV_MAJOR(scpi_info->protocol_version),
-		       PROTOCOL_REV_MINOR(scpi_info->protocol_version));
+	return sprintf(buf, "%lu.%lu\n",
+		FIELD_GET(PROTO_REV_MAJOR_MASK, scpi_info->protocol_version),
+		FIELD_GET(PROTO_REV_MINOR_MASK, scpi_info->protocol_version));
 }
 static DEVICE_ATTR_RO(protocol_version);
 
 static ssize_t firmware_version_show(struct device *dev,
 				     struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%d.%d.%d\n",
-		       FW_REV_MAJOR(scpi_info->firmware_version),
-		       FW_REV_MINOR(scpi_info->firmware_version),
-		       FW_REV_PATCH(scpi_info->firmware_version));
+	return sprintf(buf, "%lu.%lu.%lu\n",
+		     FIELD_GET(FW_REV_MAJOR_MASK, scpi_info->firmware_version),
+		     FIELD_GET(FW_REV_MINOR_MASK, scpi_info->firmware_version),
+		     FIELD_GET(FW_REV_PATCH_MASK, scpi_info->firmware_version));
 }
 static DEVICE_ATTR_RO(firmware_version);
 
@@ -1021,12 +1016,12 @@ static int scpi_probe(struct platform_device *pdev)
 
 	scpi_dvfs_populate(dev);
 
-	_dev_info(dev, "SCP Protocol %d.%d Firmware %d.%d.%d version\n",
-		  PROTOCOL_REV_MAJOR(scpi_info->protocol_version),
-		  PROTOCOL_REV_MINOR(scpi_info->protocol_version),
-		  FW_REV_MAJOR(scpi_info->firmware_version),
-		  FW_REV_MINOR(scpi_info->firmware_version),
-		  FW_REV_PATCH(scpi_info->firmware_version));
+	_dev_info(dev, "SCP Protocol %lu.%lu Firmware %lu.%lu.%lu version\n",
+		  FIELD_GET(PROTO_REV_MAJOR_MASK, scpi_info->protocol_version),
+		  FIELD_GET(PROTO_REV_MINOR_MASK, scpi_info->protocol_version),
+		  FIELD_GET(FW_REV_MAJOR_MASK, scpi_info->firmware_version),
+		  FIELD_GET(FW_REV_MINOR_MASK, scpi_info->firmware_version),
+		  FIELD_GET(FW_REV_PATCH_MASK, scpi_info->firmware_version));
 
 	ret = devm_device_add_groups(dev, versions_groups);
 	if (ret)
-- 
2.14.2

[PATCH 3/3] firmware: arm_scpi: improve struct sensor_value

[Heiner Kallweit]

lo_val and hi_val together in this order are a little endian 64 bit value.
Therefore we can simplify struct sensor_value and the code by defining
it as a __le64 value and by using le64_to_cpu.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 drivers/firmware/arm_scpi.c | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/drivers/firmware/arm_scpi.c b/drivers/firmware/arm_scpi.c
index d305b926..c923d1eb 100644
--- a/drivers/firmware/arm_scpi.c
+++ b/drivers/firmware/arm_scpi.c
@@ -347,9 +347,8 @@ struct _scpi_sensor_info {
 };
 
 struct sensor_value {
-	__le32 lo_val;
-	__le32 hi_val;
-} __packed;
+	__le64 val;
+};
 
 struct dev_pstate_set {
 	__le16 dev_id;
@@ -785,11 +784,10 @@ static int scpi_sensor_get_value(u16 sensor, u64 *val)
 		return ret;
 
 	if (scpi_info->is_legacy)
-		/* only 32-bits supported, hi_val can be junk */
-		*val = le32_to_cpu(buf.lo_val);
+		/* only 32-bits supported, upper 32 bits can be junk */
+		*val = le32_to_cpup((__le32 *)&buf.val);
 	else
-		*val = (u64)le32_to_cpu(buf.hi_val) << 32 |
-			le32_to_cpu(buf.lo_val);
+		*val = le64_to_cpu(buf.val);
 
 	return 0;
 }
-- 
2.14.2

[PATCH 1/3] firmware: arm_scpi: improve struct dvfs_info to make code better readable

[Sudeep Holla]

On 04/10/17 19:56, Heiner Kallweit wrote:
> Making the header subfields members of struct dvfs_info allows to make
> the code better readable and avoids some macro magic.
> 
> In addition remove a useless statement using info->latency.
> 

All 3 looks trivial and applied now. Thanks for the cleanup.

I found couple of other trivial things that can be cleaned. I will CC
you on them, it would be good if you can review and/or test.

I need to send PR by end of this week or early next week.

-- 
Regards,
Sudeep