[PATCH 3/3] memory: brcmstb_memc: Add new DDR attributes

Florian Fainelli f.fainelli at gmail.com
Fri Mar 24 09:52:31 PDT 2023


Provide information about the DDR size, type, width, total width,
dual/single rank. This is useful for reporting purposes and inventory of
the system(s).

Signed-off-by: Florian Fainelli <f.fainelli at gmail.com>
---
 drivers/memory/brcmstb_memc.c | 80 ++++++++++++++++++++++++++++++++++-
 1 file changed, 79 insertions(+), 1 deletion(-)

diff --git a/drivers/memory/brcmstb_memc.c b/drivers/memory/brcmstb_memc.c
index 67c75e21c95e..032567dfd6e2 100644
--- a/drivers/memory/brcmstb_memc.c
+++ b/drivers/memory/brcmstb_memc.c
@@ -13,7 +13,14 @@
 
 #define REG_MEMC_CNTRLR_CONFIG		0x00
 #define  CNTRLR_CONFIG_LPDDR4_SHIFT	5
-#define  CNTRLR_CONFIG_MASK		0xf
+#define  CNTRLR_CONFIG_MASK		GENMASK(3, 0)
+#define  CNTRLR_CONFIG_SIZE_SHIFT	4
+#define  CNTRLR_CONFIG_SIZE_MASK	GENMASK(7, 4)
+#define  CNTRLR_CONFIG_WIDTH_SHIFT	8
+#define  CNTRLR_CONFIG_WIDTH_MASK	GENMASK(9, 8)
+#define  CNTRLR_CONFIG_TOT_WIDTH_SHIFT	10
+#define  CNTRLR_CONFIG_TOT_WIDTH_MASK	GENMASK(11, 10)
+#define  CNTRLR_CONFIG_RANK_SHIFT	16
 #define REG_MEMC_SRPD_CFG_21		0x20
 #define REG_MEMC_SRPD_CFG_20		0x34
 #define REG_MEMC_SRPD_CFG_1x		0x3c
@@ -63,6 +70,67 @@ static int brcmstb_memc_srpd_config(struct brcmstb_memc *memc,
 	return 0;
 }
 
+static ssize_t ddr_rank_show(struct device *dev,
+			     struct device_attribute *attr, char *buf)
+{
+	struct brcmstb_memc *memc = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%s\n",
+		       memc->config_reg & CNTRLR_CONFIG_RANK_SHIFT ?
+		       "dual" : "single");
+}
+
+static ssize_t ddr_size_show(struct device *dev,
+			     struct device_attribute *attr, char *buf)
+{
+	struct brcmstb_memc *memc = dev_get_drvdata(dev);
+	u32 val = (memc->config_reg & CNTRLR_CONFIG_SIZE_MASK) >>
+		  CNTRLR_CONFIG_SIZE_SHIFT;
+
+	return sprintf(buf, "%dMb\n", 256 << val);
+}
+
+static ssize_t ddr_total_width_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct brcmstb_memc *memc = dev_get_drvdata(dev);
+	u32 val = (memc->config_reg & CNTRLR_CONFIG_TOT_WIDTH_MASK) >>
+		   CNTRLR_CONFIG_TOT_WIDTH_SHIFT;
+
+	return sprintf(buf, "x%d\n", 8 << val);
+}
+
+static ssize_t ddr_type_show(struct device *dev,
+			     struct device_attribute *attr, char *buf)
+{
+	struct brcmstb_memc *memc = dev_get_drvdata(dev);
+	const char *ddr_type_to_str[] = {
+		"DDR2",
+		"DDR3",
+		"DDR4",
+		"GDDR5M",
+		"GDDR5",
+		"LPDDR4",
+	};
+	u32 val = memc->config_reg & CNTRLR_CONFIG_MASK;
+	const char *type = "unknown";
+
+	if (val < ARRAY_SIZE(ddr_type_to_str))
+		type = ddr_type_to_str[val];
+
+	return sprintf(buf, "%s\n", type);
+}
+
+static ssize_t ddr_width_show(struct device *dev,
+			      struct device_attribute *attr, char *buf)
+{
+	struct brcmstb_memc *memc = dev_get_drvdata(dev);
+	u32 val = (memc->config_reg & CNTRLR_CONFIG_WIDTH_MASK) >>
+		  CNTRLR_CONFIG_WIDTH_SHIFT;
+
+	return sprintf(buf, "x%d\n", 8 << val);
+}
+
 static ssize_t frequency_show(struct device *dev,
 			      struct device_attribute *attr, char *buf)
 {
@@ -105,10 +173,20 @@ static ssize_t srpd_store(struct device *dev, struct device_attribute *attr,
 	return count;
 }
 
+static DEVICE_ATTR_RO(ddr_rank);
+static DEVICE_ATTR_RO(ddr_size);
+static DEVICE_ATTR_RO(ddr_total_width);
+static DEVICE_ATTR_RO(ddr_type);
+static DEVICE_ATTR_RO(ddr_width);
 static DEVICE_ATTR_RO(frequency);
 static DEVICE_ATTR_RW(srpd);
 
 static struct attribute *dev_attrs[] = {
+	&dev_attr_ddr_rank.attr,
+	&dev_attr_ddr_size.attr,
+	&dev_attr_ddr_total_width.attr,
+	&dev_attr_ddr_type.attr,
+	&dev_attr_ddr_width.attr,
 	&dev_attr_frequency.attr,
 	&dev_attr_srpd.attr,
 	NULL,
-- 
2.34.1




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