Fix DIMM temperature reads

FIFO4 register requires a 4 byte read or will hang.
OCC will request 4 byte read, but only look at first 2 for temperature.
FIFO register can only read one byte per request which is less efficient.

Change-Id: Ia0bbbc70f5b7de76f1bea64279b2ff7dd5b5a861
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/35974
Tested-by: FSP CI Jenkins <fsp-CI-jenkins+hostboot@us.ibm.com>
Reviewed-by: Martha Broyles <mbroyles@us.ibm.com>
Reviewed-by: William A. Bryan <wilbryan@us.ibm.com>
Reviewed-by: Christopher J. Cain <cjcain@us.ibm.com>

4 files changed, 14 insertions, 23 deletions

diff --git a/src/occ_gpe1/gpe1.h b/src/occ_gpe1/gpe1.h
index af26829..4ce0823 100755
--- a/src/occ_gpe1/gpe1.h
+++ b/src/occ_gpe1/gpe1.h
@@ -48,14 +48,6 @@
 #define I2C_FIFO4_REG_READ          0x000A0012
 
 
-// I2C Status Reigster masks
-#define STATUS_ERROR_MASK               0xFE80330000000000
-#define STATUS_ERROR_OR_COMPLETE_MASK   0xFF80330000000000
-#define STATUS_COMPLETE_MASK            0x0100000000000000
-#define PEEK_ERROR_MASK                 0x00000000FC000000
-#define PEEK_MORE_DATA                  0x0000000002000000
-
-
 // Debug trace
 #ifdef GPE1_DEBUG
   #define GPE1_DIMM_DBG(frmt,args...)  \
diff --git a/src/occ_gpe1/gpe1_dimm.h b/src/occ_gpe1/gpe1_dimm.h
index c3249c6..b151f87 100755
--- a/src/occ_gpe1/gpe1_dimm.h
+++ b/src/occ_gpe1/gpe1_dimm.h
@@ -44,9 +44,9 @@
 
 #define SCOM_ENGINE_OFFSET(engine) (engine << 12)
 
-// I2C Status Reigster masks
-#define STATUS_ERROR_MASK               0xFE80330000000000
-#define STATUS_ERROR_OR_COMPLETE_MASK   0xFF80330000000000
+// I2C Status Register masks
+#define STATUS_ERROR_MASK               0xFC80000000000000
+#define STATUS_ERROR_OR_COMPLETE_MASK   0xFF80000000000000
 #define STATUS_COMPLETE_MASK            0x0100000000000000
 #define PEEK_ERROR_MASK                 0x00000000FC000000
 #define PEEK_MORE_DATA                  0x0000000002000000
diff --git a/src/occ_gpe1/gpe1_dimm_control.c b/src/occ_gpe1/gpe1_dimm_control.c
index 65ca4b6..a87a464 100644
--- a/src/occ_gpe1/gpe1_dimm_control.c
+++ b/src/occ_gpe1/gpe1_dimm_control.c
@@ -146,15 +146,16 @@ void gpe_reset_mem_deadman(ipc_msg_t* cmd, void* arg)
     ipc_async_cmd_t *async_cmd = (ipc_async_cmd_t*)cmd;
     reset_mem_deadman_args_t *args = (reset_mem_deadman_args_t*)async_cmd->cmd_data;
 
-    int mca = args->mca; // Nimbus MCA; mc_pair = mca >>2 and port = mca & 3
-
     args->error.error = 0;
     args->error.ffdc = 0;
 
     do
     {   // read Deadman timer's SCOM Register for specified MCA (MC pair and port numbers)
         // @TODO: uncomment when deadman timer scom registers are definied in simics. RTC: 163713, RTC: 163934
-        //rc = getscom_abs(DEADMAN_TIMER_MCA(mca), &regValue);
+#if 0
+        int mca = args->mca; // Nimbus MCA; mc_pair = mca >>2 and port = mca & 3
+
+        rc = getscom_abs(DEADMAN_TIMER_MCA(mca), &regValue);
         if(rc)
         {
             PK_TRACE("gpe_reset_mem_deadman: Deadman timer read failed"
@@ -172,6 +173,7 @@ void gpe_reset_mem_deadman(ipc_msg_t* cmd, void* arg)
                      mca, DEADMAN_TIMER_MCA(mca), regValue);
 
         }
+#endif
     } while(0);
 
     // send back a response, IPC success even if ffdc/rc are non zeros
diff --git a/src/occ_gpe1/gpe1_dimm_read.c b/src/occ_gpe1/gpe1_dimm_read.c
index e0ee84c..86d80b6 100644
--- a/src/occ_gpe1/gpe1_dimm_read.c
+++ b/src/occ_gpe1/gpe1_dimm_read.c
@@ -370,10 +370,12 @@ void dimm_initiate_read(ipc_msg_t* cmd, void* arg)
         if ((regValue & STATUS_ERROR_OR_COMPLETE_MASK) == STATUS_COMPLETE_MASK)
         {
             // Status register indicates no errors and last command completed.
-            // Write the I2C command register with a 2 byte read request
+            // Write the I2C command register with a 2 byte read request.
+            // Since FIFO4 can read 4 bytes in one operation, we will do a read of 4 bytes
+            // and only look at first 2 bytes.  (FIFO4 will hang if only try to read 2 bytes)
             scomAddr = I2C_COMMAND_REG | SCOM_ENGINE_OFFSET(args->i2cEngine);
-            // start+address+stop + slave_address, rw=1=read, length=2
-            regValue  = 0xD001000200000000;
+            // start+address+stop + slave_address, rw=1=read, length=4
+            regValue  = 0xD001000400000000;
             regValue |= ((uint64_t)args->i2cAddr << 48);
             rc = putscom_abs(scomAddr, regValue);
             if(rc)
@@ -497,12 +499,7 @@ void dimm_read_temp(ipc_msg_t* cmd, void* arg)
                                  WORD_HIGH(regValue), WORD_LOW(regValue));
                         gpe_set_ffdc(&(args->error), scomAddr, GPE_RC_I2C_ERROR, regValue);
                     }
-                    else if (regValue & PEEK_MORE_DATA)
-                    {
-                        // The data_request bit is non-zero, but no more data is needed!
-                        PK_TRACE("dimm_read_temp: Got data, but more data needs access??");
-                        gpe_set_ffdc(&(args->error), scomAddr, GPE_RC_NOT_COMPLETE, regValue);
-                    }
+                    // PEEK_MORE_DATA will be set because we only read 2 of the 4 bytes (ignore this bit)
                 }
             }
             // else, all data not available yet (NOT_COMPLETE)