[U-Boot] [PATCH 156/172] ddr: altera: Clean up rw_mgr_mem_calibrate_writes_center() part 1

Marek Vasut
2015-07-27T20:51:59Z

Fix data types and constify where applicable, fix broken multiline
debug strings and fix comments. No functional change.

Signed-off-by: Marek Vasut <marex@denx.de>
---
drivers/ddr/altera/sequencer.c | 124 +++++++++++++++++++++--------------------
1 file changed, 63 insertions(+), 61 deletions(-)

diff --git a/drivers/ddr/altera/sequencer.c b/drivers/ddr/altera/sequencer.c
index b81fc8c..e99ecb4 100644
--- a/drivers/ddr/altera/sequencer.c
+++ b/drivers/ddr/altera/sequencer.c
@@ -2887,24 +2887,26 @@ static uint32_t rw_mgr_mem_calibrate_write_test(uint32_t rank_bgn,
* center all windows. do per-bit-deskew to possibly increase size of
* certain windows.
*/
-static uint32_t rw_mgr_mem_calibrate_writes_center(uint32_t rank_bgn,
- uint32_t write_group, uint32_t test_bgn)
+static int
+rw_mgr_mem_calibrate_writes_center(const u32 rank_bgn, const u32 write_group,
+ const u32 test_bgn)
{
- uint32_t i, min_index;
- int32_t d;
- /*
- * Store these as signed since there are comparisons with
- * signed numbers.
- */
- uint32_t bit_chk;
- uint32_t sticky_bit_chk;
- int32_t left_edge[RW_MGR_MEM_DQ_PER_WRITE_DQS];
- int32_t right_edge[RW_MGR_MEM_DQ_PER_WRITE_DQS];
- int32_t mid;
- int32_t mid_min, orig_mid_min;
- int32_t new_dqs, start_dqs;
- int32_t dq_margin, dqs_margin, dm_margin;
- uint32_t addr;
+ int i, d;
+ u32 bit_chk;
+ u32 sticky_bit_chk;
+ u32 min_index;
+ u32 addr;
+ int left_edge[RW_MGR_MEM_DQ_PER_WRITE_DQS];
+ int right_edge[RW_MGR_MEM_DQ_PER_WRITE_DQS];
+ int mid;
+ int mid_min, orig_mid_min;
+ int new_dqs, start_dqs;
+ int dq_margin, dqs_margin, dm_margin;
+ int bgn_curr = IO_IO_OUT1_DELAY_MAX + 1;
+ int end_curr = IO_IO_OUT1_DELAY_MAX + 1;
+ int bgn_best = IO_IO_OUT1_DELAY_MAX + 1;
+ int end_best = IO_IO_OUT1_DELAY_MAX + 1;
+ int win_best = 0;

int ret;

@@ -2916,11 +2918,11 @@ static uint32_t rw_mgr_mem_calibrate_writes_center(uint32_t rank_bgn,
start_dqs = readl(addr +
(RW_MGR_MEM_DQ_PER_WRITE_DQS << 2));

- /* per-bit deskew */
+ /* Per-bit deskew. */

/*
- * set the left and right edge of each bit to an illegal value
- * use (IO_IO_OUT1_DELAY_MAX + 1) as an illegal value.
+ * Set the left and right edge of each bit to an illegal value.
+ * Use (IO_IO_OUT1_DELAY_MAX + 1) as an illegal value.
*/
sticky_bit_chk = 0;
for (i = 0; i < RW_MGR_MEM_DQ_PER_WRITE_DQS; i++) {
@@ -2928,12 +2930,12 @@ static uint32_t rw_mgr_mem_calibrate_writes_center(uint32_t rank_bgn,
right_edge[i] = IO_IO_OUT1_DELAY_MAX + 1;
}

- /* Search for the left edge of the window for each bit */
+ /* Search for the left edge of the window for each bit. */
search_left_edge(1, rank_bgn, write_group, 0, test_bgn,
&sticky_bit_chk,
left_edge, right_edge, 0);

- /* Search for the right edge of the window for each bit */
+ /* Search for the right edge of the window for each bit. */
ret = search_right_edge(1, rank_bgn, write_group, 0,
start_dqs, 0,
&sticky_bit_chk,
@@ -2946,12 +2948,13 @@ static uint32_t rw_mgr_mem_calibrate_writes_center(uint32_t rank_bgn,

min_index = get_window_mid_index(1, left_edge, right_edge, &mid_min);

- /* Determine the amount we can change DQS (which is -mid_min) */
+ /* Determine the amount we can change DQS (which is -mid_min). */
orig_mid_min = mid_min;
new_dqs = start_dqs;
mid_min = 0;
- debug_cond(DLEVEL == 1, "%s:%d write_center: start_dqs=%d new_dqs=%d \
- mid_min=%d\n", __func__, __LINE__, start_dqs, new_dqs, mid_min);
+ debug_cond(DLEVEL == 1,
+ "%s:%d write_center: start_dqs=%d new_dqs=%d mid_min=%d\n",
+ __func__, __LINE__, start_dqs, new_dqs, mid_min);

/* Add delay to bring centre of all DQ windows to the same "level". */
center_dq_windows(1, left_edge, right_edge, mid_min, orig_mid_min,
@@ -2965,18 +2968,13 @@ static uint32_t rw_mgr_mem_calibrate_writes_center(uint32_t rank_bgn,
debug_cond(DLEVEL == 2, "%s:%d write_center: DM\n", __func__, __LINE__);

/*
- * set the left and right edge of each bit to an illegal value,
- * use (IO_IO_OUT1_DELAY_MAX + 1) as an illegal value,
+ * Set the left and right edge of each bit to an illegal value.
+ * Use (IO_IO_OUT1_DELAY_MAX + 1) as an illegal value.
*/
left_edge[0] = IO_IO_OUT1_DELAY_MAX + 1;
right_edge[0] = IO_IO_OUT1_DELAY_MAX + 1;
- int32_t bgn_curr = IO_IO_OUT1_DELAY_MAX + 1;
- int32_t end_curr = IO_IO_OUT1_DELAY_MAX + 1;
- int32_t bgn_best = IO_IO_OUT1_DELAY_MAX + 1;
- int32_t end_best = IO_IO_OUT1_DELAY_MAX + 1;
- int32_t win_best = 0;

- /* Search for the/part of the window with DM shift */
+ /* Search for the/part of the window with DM shift. */
for (d = IO_IO_OUT1_DELAY_MAX; d >= 0; d -= DELTA_D) {
scc_mgr_apply_group_dm_out1_delay(d);
writel(0, &sdr_scc_mgr->update);
@@ -2984,7 +2982,7 @@ static uint32_t rw_mgr_mem_calibrate_writes_center(uint32_t rank_bgn,
if (rw_mgr_mem_calibrate_write_test(rank_bgn, write_group, 1,
PASS_ALL_BITS, &bit_chk,
0)) {
- /* USE Set current end of the window */
+ /* Set current end of the window. */
end_curr = -d;
/*
* If a starting edge of our window has not been seen
@@ -3003,26 +3001,26 @@ static uint32_t rw_mgr_mem_calibrate_writes_center(uint32_t rank_bgn,
end_best = end_curr;
}
} else {
- /* We just saw a failing test. Reset temp edge */
+ /* We just saw a failing test. Reset temp edge. */
bgn_curr = IO_IO_OUT1_DELAY_MAX + 1;
end_curr = IO_IO_OUT1_DELAY_MAX + 1;
- }
}
+ }

-
- /* Reset DM delay chains to 0 */
+ /* Reset DM delay chains to 0. */
scc_mgr_apply_group_dm_out1_delay(0);

/*
* Check to see if the current window nudges up aganist 0 delay.
* If so we need to continue the search by shifting DQS otherwise DQS
- * search begins as a new search. */
+ * search begins as a new search.
+ */
if (end_curr != 0) {
bgn_curr = IO_IO_OUT1_DELAY_MAX + 1;
end_curr = IO_IO_OUT1_DELAY_MAX + 1;
}

- /* Search for the/part of the window with DQS shifts */
+ /* Search for the/part of the window with DQS shifts. */
for (d = 0; d <= IO_IO_OUT1_DELAY_MAX - new_dqs; d += DELTA_D) {
/*
* Note: This only shifts DQS, so are we limiting ourselve to
@@ -3035,7 +3033,7 @@ static uint32_t rw_mgr_mem_calibrate_writes_center(uint32_t rank_bgn,
if (rw_mgr_mem_calibrate_write_test(rank_bgn, write_group, 1,
PASS_ALL_BITS, &bit_chk,
0)) {
- /* USE Set current end of the window */
+ /* Set current end of the window. */
end_curr = d;
/*
* If a beginning edge of our window has not been seen
@@ -3054,40 +3052,42 @@ static uint32_t rw_mgr_mem_calibrate_writes_center(uint32_t rank_bgn,
end_best = end_curr;
}
} else {
- /* We just saw a failing test. Reset temp edge */
+ /* We just saw a failing test. Reset temp edge. */
bgn_curr = IO_IO_OUT1_DELAY_MAX + 1;
end_curr = IO_IO_OUT1_DELAY_MAX + 1;

- /* Early exit optimization: if ther remaining delay
- chain space is less than already seen largest window
- we can exit */
+ /*
+ * Early exit optimization: if the remaining delay
+ * chain space is less than already seen largest
+ * window we can exit.
+ */
if ((win_best-1) >
(IO_IO_OUT1_DELAY_MAX - new_dqs - d)) {
break;
- }
}
}
+ }

- /* assign left and right edge for cal and reporting; */
- left_edge[0] = -1*bgn_best;
+ /* Assign left and right edge for cal and reporting. */
+ left_edge[0] = -1 * bgn_best;
right_edge[0] = end_best;

- debug_cond(DLEVEL == 2, "%s:%d dm_calib: left=%d right=%d\n", __func__,
- __LINE__, left_edge[0], right_edge[0]);
+ debug_cond(DLEVEL == 2, "%s:%d dm_calib: left=%d right=%d\n",
+ __func__, __LINE__, left_edge[0], right_edge[0]);

- /* Move DQS (back to orig) */
+ /* Move DQS (back to orig). */
scc_mgr_apply_group_dqs_io_and_oct_out1(write_group, new_dqs);

/* Move DM */

- /* Find middle of window for the DM bit */
+ /* Find middle of window for the DM bit. */
mid = (left_edge[0] - right_edge[0]) / 2;

- /* only move right, since we are not moving DQS/DQ */
+ /* Only move right, since we are not moving DQS/DQ. */
if (mid < 0)
mid = 0;

- /* dm_marign should fail if we never find a window */
+ /* dm_marign should fail if we never find a window. */
if (win_best == 0)
dm_margin = -1;
else
@@ -3096,21 +3096,23 @@ static uint32_t rw_mgr_mem_calibrate_writes_center(uint32_t rank_bgn,
scc_mgr_apply_group_dm_out1_delay(mid);
writel(0, &sdr_scc_mgr->update);

- debug_cond(DLEVEL == 2, "%s:%d dm_calib: left=%d right=%d mid=%d \
- dm_margin=%d\n", __func__, __LINE__, left_edge[0],
- right_edge[0], mid, dm_margin);
- /* Export values */
+ debug_cond(DLEVEL == 2,
+ "%s:%d dm_calib: left=%d right=%d mid=%d dm_margin=%d\n",
+ __func__, __LINE__, left_edge[0], right_edge[0],
+ mid, dm_margin);
+ /* Export values. */
gbl->fom_out += dq_margin + dqs_margin;

- debug_cond(DLEVEL == 2, "%s:%d write_center: dq_margin=%d \
- dqs_margin=%d dm_margin=%d\n", __func__, __LINE__,
- dq_margin, dqs_margin, dm_margin);
+ debug_cond(DLEVEL == 2,
+ "%s:%d write_center: dq_margin=%d dqs_margin=%d dm_margin=%d\n",
+ __func__, __LINE__, dq_margin, dqs_margin, dm_margin);

/*
* Do not remove this line as it makes sure all of our
* decisions have been applied.
*/
writel(0, &sdr_scc_mgr->update);
+
return (dq_margin >= 0) && (dqs_margin >= 0) && (dm_margin >= 0);
}

--
2.1.4