On 04/08/2015 12:00 AM, Cédric Le Goater wrote:
The new OPAL device tree adds a few properties which can be used to add
extra information on the sensor label.
In the case of a cpu core sensor, the firmware exposes the physical
identifier of the core in the "ibm,pir" property. The driver
translates this identifier in a linux cpu number and prints out a
range corresponding to the hardware threads of the core (as they
share the same sensor).
The numbering gives a hint on the localization of the core in the
system (which socket, which chip).
Signed-off-by: Cédric Le Goater <c...@fr.ibm.com>
---
Changes since v2:
- fix bogus logical cpu retrieval
- use 'threads_per_core' to print out cpu range
Changes since v1:
- check cpu validity before printing out the attribute label.
if invalid, use a "phy" prefix to distinguish a linux cpu
number from a physical cpu number.
drivers/hwmon/ibmpowernv.c | 43 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 43 insertions(+)
Index: linux.git/drivers/hwmon/ibmpowernv.c
===================================================================
--- linux.git.orig/drivers/hwmon/ibmpowernv.c
+++ linux.git/drivers/hwmon/ibmpowernv.c
@@ -30,6 +30,7 @@
#include <linux/platform_device.h>
#include <asm/opal.h>
#include <linux/err.h>
+#include <asm/cputhreads.h>
#define MAX_ATTR_LEN 32
#define MAX_LABEL_LEN 64
@@ -110,12 +111,54 @@ static ssize_t show_label(struct device
return sprintf(buf, "%s\n", sdata->label);
}
+static int __init get_logical_cpu(unsigned int hwcpu)
+{
+ int cpu;
+
+ for_each_possible_cpu(cpu)
+ if (get_hard_smp_processor_id(cpu) == hwcpu)
+ return cpu;
+
+ pr_err("%s: could not find a cpu with physical id 0x%x\n",
+ __func__, hwcpu);
I like moving this into a function, but I really dislike this error
message. If the devicetree data is wrong/bad, the log and the console
will be clogged with that message. And the user will not be able
to do anything about it.
Guenter
+ return -ENOENT;
+}
+
static void __init make_sensor_label(struct device_node *np,
struct sensor_data *sdata, const char *label)
{
+ u32 id;
size_t n;
n = snprintf(sdata->label, sizeof(sdata->label), "%s", label);
+
+ /*
+ * Core temp pretty print
+ */
+ if (!of_property_read_u32(np, "ibm,pir", &id)) {
+ int cpuid = get_logical_cpu(id);
+
+ if (cpuid >= 0)
+ /*
+ * The digital thermal sensors are associated
+ * with a core. Let's print out the range of
+ * cpu ids corresponding to the hardware
+ * threads of the core.
+ */
+ n += snprintf(sdata->label + n,
+ sizeof(sdata->label) - n, " %d-%d",
+ cpuid, cpuid + threads_per_core - 1);
+ else
+ n += snprintf(sdata->label + n,
+ sizeof(sdata->label) - n, " phy%d", id);
+ }
+
+ /*
+ * Membuffer pretty print
+ */
+ if (!of_property_read_u32(np, "ibm,chip-id", &id))
+ n += snprintf(sdata->label + n, sizeof(sdata->label) - n,
+ " %d", id & 0xffff);
}
static int get_sensor_index_attr(const char *name, u32 *index,
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