ddr: altera: Clean up rw_mgr_mem_calibrate_lfifo()

Minor coding style cleanup, add kerneldoc. No functional change.

Signed-off-by: Marek Vasut <marex@denx.de>

diff --git a/drivers/ddr/altera/sequencer.c b/drivers/ddr/altera/sequencer.c
index 2baf77dd7782e491be6c20d1cd73c0eee3b6e77c..eb0e8cf2593e24b00046326badd5e8b38efe4981 100644 (file)
--- a/drivers/ddr/altera/sequencer.c
+++ b/drivers/ddr/altera/sequencer.c
@@ -2818,60 +2818,65 @@ static int rw_mgr_mem_calibrate_vfifo_end(const u32 rw_group,
        return ret;
 }
 
-/* Calibrate LFIFO to find smallest read latency */
+/**
+ * rw_mgr_mem_calibrate_lfifo() - Minimize latency
+ *
+ * Stage 4: Minimize latency.
+ *
+ * This function implements UniPHY calibration Stage 4, as explained in
+ * detail in Altera EMI_RM 2015.05.04 , "UniPHY Calibration Stages".
+ * Calibrate LFIFO to find smallest read latency.
+ */
 static uint32_t rw_mgr_mem_calibrate_lfifo(void)
 {
-       uint32_t found_one;
+       int found_one = 0;
 
        debug("%s:%d\n", __func__, __LINE__);
 
-       /* update info for sims */
+       /* Update info for sims. */
        reg_file_set_stage(CAL_STAGE_LFIFO);
        reg_file_set_sub_stage(CAL_SUBSTAGE_READ_LATENCY);
 
        /* Load up the patterns used by read calibration for all ranks */
        rw_mgr_mem_calibrate_read_load_patterns(0, 1);
-       found_one = 0;
 
        do {
                writel(gbl->curr_read_lat, &phy_mgr_cfg->phy_rlat);
                debug_cond(DLEVEL == 2, "%s:%d lfifo: read_lat=%u",
                           __func__, __LINE__, gbl->curr_read_lat);
 
-               if (!rw_mgr_mem_calibrate_read_test_all_ranks(0,
-                                                             NUM_READ_TESTS,
-                                                             PASS_ALL_BITS,
-                                                             1)) {
+               if (!rw_mgr_mem_calibrate_read_test_all_ranks(0, NUM_READ_TESTS,
+                                                             PASS_ALL_BITS, 1))
                        break;
-               }
 
                found_one = 1;
-               /* reduce read latency and see if things are working */
-               /* correctly */
+               /*
+                * Reduce read latency and see if things are
+                * working correctly.
+                */
                gbl->curr_read_lat--;
        } while (gbl->curr_read_lat > 0);
 
-       /* reset the fifos to get pointers to known state */
-
+       /* Reset the fifos to get pointers to known state. */
        writel(0, &phy_mgr_cmd->fifo_reset);
 
        if (found_one) {
-               /* add a fudge factor to the read latency that was determined */
+               /* Add a fudge factor to the read latency that was determined */
                gbl->curr_read_lat += 2;
                writel(gbl->curr_read_lat, &phy_mgr_cfg->phy_rlat);
-               debug_cond(DLEVEL == 2, "%s:%d lfifo: success: using \
-                          read_lat=%u\n", __func__, __LINE__,
-                          gbl->curr_read_lat);
-               return 1;
+               debug_cond(DLEVEL == 2,
+                          "%s:%d lfifo: success: using read_lat=%u\n",
+                          __func__, __LINE__, gbl->curr_read_lat);
        } else {
                set_failing_group_stage(0xff, CAL_STAGE_LFIFO,
                                        CAL_SUBSTAGE_READ_LATENCY);
 
-               debug_cond(DLEVEL == 2, "%s:%d lfifo: failed at initial \
-                          read_lat=%u\n", __func__, __LINE__,
-                          gbl->curr_read_lat);
-               return 0;
+               debug_cond(DLEVEL == 2,
+                          "%s:%d lfifo: failed at initial read_lat=%u\n",
+                          __func__, __LINE__, gbl->curr_read_lat);
        }
+
+       return found_one;
 }
 
 /**