From 080bf64ef1b3bcf8703a3bc4a8474314ea7c0071 Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Mon, 20 Jul 2015 08:15:57 +0200 Subject: [PATCH] ddr: altera: Clean up set_rank_and_odt_mask() part 3 Clean up comments and add kerneldoc. Signed-off-by: Marek Vasut --- drivers/ddr/altera/sequencer.c | 34 ++++++++++++++++++++-------------- 1 file changed, 20 insertions(+), 14 deletions(-) diff --git a/drivers/ddr/altera/sequencer.c b/drivers/ddr/altera/sequencer.c index f7b5f526c5..56ca6f377c 100644 --- a/drivers/ddr/altera/sequencer.c +++ b/drivers/ddr/altera/sequencer.c @@ -154,6 +154,13 @@ static void phy_mgr_initialize(void) param->dm_correct_mask = (1 << ratio) - 1; } +/** + * set_rank_and_odt_mask() - Set Rank and ODT mask + * @rank: Rank mask + * @odt_mode: ODT mode, OFF or READ_WRITE + * + * Set Rank and ODT mask (On-Die Termination). + */ static void set_rank_and_odt_mask(const u32 rank, const u32 odt_mode) { u32 odt_mask_0 = 0; @@ -172,14 +179,15 @@ static void set_rank_and_odt_mask(const u32 rank, const u32 odt_mode) break; case 2: /* 2 Ranks */ if (RW_MGR_MEM_NUMBER_OF_CS_PER_DIMM == 1) { - /* - Dual-Slot , Single-Rank - * (1 chip-select per DIMM) - * OR - * - RDIMM, 4 total CS (2 CS per DIMM) - * means 2 DIMM - * Since MEM_NUMBER_OF_RANKS is 2 they are - * both single rank - * with 2 CS each (special for RDIMM) + /* + * - Dual-Slot , Single-Rank (1 CS per DIMM) + * OR + * - RDIMM, 4 total CS (2 CS per DIMM, 2 DIMM) + * + * Since MEM_NUMBER_OF_RANKS is 2, they + * are both single rank with 2 CS each + * (special for RDIMM). + * * Read: Turn on ODT on the opposite rank * Write: Turn on ODT on all ranks */ @@ -187,10 +195,10 @@ static void set_rank_and_odt_mask(const u32 rank, const u32 odt_mode) odt_mask_1 = 0x3; } else { /* - * USER - Single-Slot , Dual-rank DIMMs - * (2 chip-selects per DIMM) - * USER Read: Turn on ODT off on all ranks - * USER Write: Turn on ODT on active rank + * - Single-Slot , Dual-Rank (2 CS per DIMM) + * + * Read: Turn on ODT off on all ranks + * Write: Turn on ODT on active rank */ odt_mask_0 = 0x0; odt_mask_1 = 0x3 & (1 << rank); @@ -199,7 +207,6 @@ static void set_rank_and_odt_mask(const u32 rank, const u32 odt_mode) case 4: /* 4 Ranks */ /* Read: * ----------+-----------------------+ - * | | * | ODT | * Read From +-----------------------+ * Rank | 3 | 2 | 1 | 0 | @@ -212,7 +219,6 @@ static void set_rank_and_odt_mask(const u32 rank, const u32 odt_mode) * * Write: * ----------+-----------------------+ - * | | * | ODT | * Write To +-----------------------+ * Rank | 3 | 2 | 1 | 0 | -- 2.30.2