Some fuse ranges are protected by the XPU such that the AP cannot
access them. Attempting to do so causes an SError. Use the newly
introduced per-soc compatible string to attach the set of regions
we should not access. Then tiptoe around those regions.
Signed-off-by: Evan Green <evgr...@chromium.org>
---
drivers/nvmem/qfprom.c | 55 +++++++++++++++++++++++++++++++++++++++---
1 file changed, 51 insertions(+), 4 deletions(-)
diff --git a/drivers/nvmem/qfprom.c b/drivers/nvmem/qfprom.c
index 5e9e60e2e591d..feea39ae52164 100644
--- a/drivers/nvmem/qfprom.c
+++ b/drivers/nvmem/qfprom.c
@@ -12,6 +12,7 @@
#include <linux/mod_devicetable.h>
#include <linux/nvmem-provider.h>
#include <linux/platform_device.h>
+#include <linux/property.h>
#include <linux/regulator/consumer.h>
/* Blow timer clock frequency in Mhz */
@@ -51,6 +52,17 @@ struct qfprom_soc_data {
u32 qfprom_blow_set_freq;
};
+/**
+ * struct qfprom_keepout_region - registers to avoid touching.
+ *
+ * @start: The first byte offset to avoid.
+ * @end: One after the last byte offset to avoid.
+ */
+struct qfprom_keepout_region {
+ u32 start;
+ u32 end;
+};
+
/**
* struct qfprom_priv - structure holding qfprom attributes
*
@@ -63,6 +75,7 @@ struct qfprom_soc_data {
* @secclk: Clock supply.
* @vcc: Regulator supply.
* @soc_data: Data that for things that varies from SoC to SoC.
+ * @keepout: Fuse regions not to access, as they may cause SErrors.
*/
struct qfprom_priv {
void __iomem *qfpraw;
@@ -73,6 +86,7 @@ struct qfprom_priv {
struct clk *secclk;
struct regulator *vcc;
const struct qfprom_soc_data *soc_data;
+ const struct qfprom_keepout_region *keepout;
};
/**
@@ -88,6 +102,12 @@ struct qfprom_touched_values {
u32 timer_val;
};
+const struct qfprom_keepout_region sc7180_qfprom[] = {
+ {.start = 0x128, .end = 0x148},
+ {.start = 0x220, .end = 0x228},
+ {} /* Sentinal where start == end. */
+};
+
/**
* qfprom_disable_fuse_blowing() - Undo enabling of fuse blowing.
* @priv: Our driver data.
@@ -171,6 +191,23 @@ static int qfprom_enable_fuse_blowing(const struct
qfprom_priv *priv,
return ret;
}
+static int qfprom_check_reg(struct qfprom_priv *priv, unsigned int reg)
+{
+ const struct qfprom_keepout_region *keepout = priv->keepout;
+
+ if (!keepout)
+ return 1;
+
+ while (keepout->start != keepout->end) {
+ if ((reg >= keepout->start) && (reg < keepout->end))
+ return 0;
+
+ keepout++;
+ }
+
+ return 1;
+}
+
/**
* qfprom_efuse_reg_write() - Write to fuses.
* @context: Our driver data.
@@ -228,8 +265,10 @@ static int qfprom_reg_write(void *context, unsigned int
reg, void *_val,
goto exit_enabled_fuse_blowing;
}
- for (i = 0; i < words; i++)
- writel(value[i], priv->qfpraw + reg + (i * 4));
+ for (i = 0; i < words; i++) {
+ if (qfprom_check_reg(priv, reg + (i * 4)))
+ writel(value[i], priv->qfpraw + reg + (i * 4));
+ }
ret = readl_relaxed_poll_timeout(
priv->qfpconf + QFPROM_BLOW_STATUS_OFFSET,
@@ -257,8 +296,14 @@ static int qfprom_reg_read(void *context,
if (read_raw_data && priv->qfpraw)
base = priv->qfpraw;
- while (words--)
- *val++ = readb(base + reg + i++);
+ while (words--) {
+ if (qfprom_check_reg(priv, reg + i))
+ *val++ = readb(base + reg + i);
+ else
+ *val++ = 0;
+
+ i++;
+ }
return 0;
}
@@ -299,6 +344,7 @@ static int qfprom_probe(struct platform_device *pdev)
econfig.priv = priv;
priv->dev = dev;
+ priv->keepout = device_get_match_data(dev);
/*
* If more than one region is provided then the OS has the ability
@@ -354,6 +400,7 @@ static int qfprom_probe(struct platform_device *pdev)
static const struct of_device_id qfprom_of_match[] = {
{ .compatible = "qcom,qfprom",},
+ { .compatible = "qcom,sc7180-qfprom", .data = &sc7180_qfprom},
{/* sentinel */},
};
MODULE_DEVICE_TABLE(of, qfprom_of_match);
--
2.26.2
