[PATCH] ppc64: SMU partition recovery

This patch adds the ability to the SMU driver to recover missing
calibration partitions from the SMU chip itself. It also adds some
dynamic mecanism to /proc/device-tree so that new properties are visible
to userland.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 143 insertions, 10 deletions

diff --git a/include/asm-powerpc/smu.h b/include/asm-powerpc/smu.h
index 959bad660233..76c29a9784dd 100644
--- a/include/asm-powerpc/smu.h
+++ b/include/asm-powerpc/smu.h
@@ -20,16 +20,52 @@
 /*
  * Partition info commands
  *
- * I do not know what those are for at this point
+ * These commands are used to retreive the sdb-partition-XX datas from
+ * the SMU. The lenght is always 2. First byte is the subcommand code
+ * and second byte is the partition ID.
+ *
+ * The reply is 6 bytes:
+ *
+ *  - 0..1 : partition address
+ *  - 2    : a byte containing the partition ID
+ *  - 3    : length (maybe other bits are rest of header ?)
+ *
+ * The data must then be obtained with calls to another command:
+ * SMU_CMD_MISC_ee_GET_DATABLOCK_REC (described below).
  */
 #define SMU_CMD_PARTITION_COMMAND               0x3e
+#define   SMU_CMD_PARTITION_LATEST              0x01
+#define   SMU_CMD_PARTITION_BASE                0x02
+#define   SMU_CMD_PARTITION_UPDATE              0x03
 
 
 /*
  * Fan control
  *
- * This is a "mux" for fan control commands, first byte is the
- * "sub" command.
+ * This is a "mux" for fan control commands. The command seem to
+ * act differently based on the number of arguments. With 1 byte
+ * of argument, this seem to be queries for fans status, setpoint,
+ * etc..., while with 0xe arguments, we will set the fans speeds.
+ *
+ * Queries (1 byte arg):
+ * ---------------------
+ *
+ * arg=0x01: read RPM fans status
+ * arg=0x02: read RPM fans setpoint
+ * arg=0x11: read PWM fans status
+ * arg=0x12: read PWM fans setpoint
+ *
+ * the "status" queries return the current speed while the "setpoint" ones
+ * return the programmed/target speed. It _seems_ that the result is a bit
+ * mask in the first byte of active/available fans, followed by 6 words (16
+ * bits) containing the requested speed.
+ *
+ * Setpoint (14 bytes arg):
+ * ------------------------
+ *
+ * first arg byte is 0 for RPM fans and 0x10 for PWM. Second arg byte is the
+ * mask of fans affected by the command. Followed by 6 words containing the
+ * setpoint value for selected fans in the mask (or 0 if mask value is 0)
  */
 #define SMU_CMD_FAN_COMMAND                     0x4a
 
@@ -156,6 +192,14 @@
 #define   SMU_CMD_POWER_SHUTDOWN                "SHUTDOWN"
 #define   SMU_CMD_POWER_VOLTAGE_SLEW            "VSLEW"
 
+/*
+ * Read ADC sensors
+ *
+ * This command takes one byte of parameter: the sensor ID (or "reg"
+ * value in the device-tree) and returns a 16 bits value
+ */
+#define SMU_CMD_READ_ADC                        0xd8
+
 /* Misc commands
  *
  * This command seem to be a grab bag of various things
@@ -176,6 +220,25 @@
  * Misc commands
  *
  * This command seem to be a grab bag of various things
+ *
+ * SMU_CMD_MISC_ee_GET_DATABLOCK_REC is used, among others, to
+ * transfer blocks of data from the SMU. So far, I've decrypted it's
+ * usage to retreive partition data. In order to do that, you have to
+ * break your transfer in "chunks" since that command cannot transfer
+ * more than a chunk at a time. The chunk size used by OF is 0xe bytes,
+ * but it seems that the darwin driver will let you do 0x1e bytes if
+ * your "PMU" version is >= 0x30. You can get the "PMU" version apparently
+ * either in the last 16 bits of property "smu-version-pmu" or as the 16
+ * bytes at offset 1 of "smu-version-info"
+ *
+ * For each chunk, the command takes 7 bytes of arguments:
+ *  byte 0: subcommand code (0x02)
+ *  byte 1: 0x04 (always, I don't know what it means, maybe the address
+ *                space to use or some other nicety. It's hard coded in OF)
+ *  byte 2..5: SMU address of the chunk (big endian 32 bits)
+ *  byte 6: size to transfer (up to max chunk size)
+ *
+ * The data is returned directly
  */
 #define SMU_CMD_MISC_ee_COMMAND                 0xee
 #define   SMU_CMD_MISC_ee_GET_DATABLOCK_REC     0x02
@@ -353,21 +416,26 @@ struct smu_sdbp_header {
         __u8    flags;
 };
 
-/*
- * 32 bits integers are usually encoded with 2x16 bits swapped,
- * this demangles them
+
+ /*
+ * demangle 16 and 32 bits integer in some SMU partitions
+ * (currently, afaik, this concerns only the FVT partition
+ * (0x12)
  */
-#define SMU_U32_MIX(x)  ((((x) << 16) & 0xffff0000u) | (((x) >> 16) & 0xffffu))
+#define SMU_U16_MIX(x)  le16_to_cpu(x);
+#define SMU_U32_MIX(x)  ((((x) & 0xff00ff00u) >> 8)|(((x) & 0x00ff00ffu) << 8))
+
 
 /* This is the definition of the SMU sdb-partition-0x12 table (called
  * CPU F/V/T operating points in Darwin). The definition for all those
  * SMU tables should be moved to some separate file
  */
-#define SMU_SDB_FVT_ID          0x12
+#define SMU_SDB_FVT_ID                  0x12
 
 struct smu_sdbp_fvt {
         __u32   sysclk;                 /* Base SysClk frequency in Hz for
-                                         * this operating point
+                                         * this operating point. Value need to
+                                         * be unmixed with SMU_U32_MIX()
                                          */
         __u8    pad;
         __u8    maxtemp;                /* Max temp. supported by this
@@ -376,10 +444,73 @@ struct smu_sdbp_fvt {
 
         __u16   volts[3];               /* CPU core voltage for the 3
                                          * PowerTune modes, a mode with
-                                         * 0V = not supported.
+                                         * 0V = not supported. Value need
+                                         * to be unmixed with SMU_U16_MIX()
                                          */
 };
 
+/* This partition contains voltage & current sensor calibration
+ * informations
+ */
+#define SMU_SDB_CPUVCP_ID               0x21
+
+struct smu_sdbp_cpuvcp {
+        __u16   volt_scale;             /* u4.12 fixed point */
+        __s16   volt_offset;            /* s4.12 fixed point */
+        __u16   curr_scale;             /* u4.12 fixed point */
+        __s16   curr_offset;            /* s4.12 fixed point */
+        __s32   power_quads[3];         /* s4.28 fixed point */
+};
+
+/* This partition contains CPU thermal diode calibration
+ */
+#define SMU_SDB_CPUDIODE_ID             0x18
+
+struct smu_sdbp_cpudiode {
+        __u16   m_value;                /* u1.15 fixed point */
+        __s16   b_value;                /* s10.6 fixed point */
+
+};
+
+/* This partition contains Slots power calibration
+ */
+#define SMU_SDB_SLOTSPOW_ID             0x78
+
+struct smu_sdbp_slotspow {
+        __u16   pow_scale;              /* u4.12 fixed point */
+        __s16   pow_offset;             /* s4.12 fixed point */
+};
+
+/* This partition contains machine specific version information about
+ * the sensor/control layout
+ */
+#define SMU_SDB_SENSORTREE_ID           0x25
+
+struct smu_sdbp_sensortree {
+        u8      model_id;
+        u8      unknown[3];
+};
+
+/* This partition contains CPU thermal control PID informations. So far
+ * only single CPU machines have been seen with an SMU, so we assume this
+ * carries only informations for those
+ */
+#define SMU_SDB_CPUPIDDATA_ID           0x17
+
+struct smu_sdbp_cpupiddata {
+        u8      unknown1;
+        u8      target_temp_delta;
+        u8      unknown2;
+        u8      history_len;
+        s16     power_adj;
+        u16     max_power;
+        s32     gp,gr,gd;
+};
+
+
+/* Other partitions without known structures */
+#define SMU_SDB_DEBUG_SWITCHES_ID       0x05
+
 #ifdef __KERNEL__
 /*
  * This returns the pointer to an SMU "sdb" partition data or NULL
@@ -423,8 +554,10 @@ struct smu_user_cmd_hdr
         __u32           cmdtype;
 #define SMU_CMDTYPE_SMU                 0       /* SMU command */
 #define SMU_CMDTYPE_WANTS_EVENTS        1       /* switch fd to events mode */
+#define SMU_CMDTYPE_GET_PARTITION       2       /* retreive an sdb partition */
 
         __u8            cmd;                    /* SMU command byte */
+        __u8            pad[3];                 /* padding */
         __u32           data_len;               /* Lenght of data following */
 };