Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757605Ab3IBJTr (ORCPT ); Mon, 2 Sep 2013 05:19:47 -0400 Received: from rtits2.realtek.com ([60.250.210.242]:41534 "EHLO rtits2.realtek.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755639Ab3IBJTp (ORCPT ); Mon, 2 Sep 2013 05:19:45 -0400 X-SpamFilter-By: BOX Solutions SpamTrap 5.34 with qID r829FwYC020379, This message is accepted by code: ctloc85258 From: To: , CC: , , , , , Micky Ching Subject: [PATCH] mmc: rtsx: change phase searching method Date: Mon, 2 Sep 2013 17:16:52 +0800 Message-ID: <1378113412-24200-1-git-send-email-micky_ching@realsil.com.cn> X-Mailer: git-send-email 1.7.9.5 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [172.29.41.103] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4422 Lines: 154 From: Micky Ching The new phase searching method is more concise, and makes the code easier to understand. Signed-off-by: Micky Ching --- drivers/mmc/host/rtsx_pci_sdmmc.c | 107 +++++++++++-------------------------- 1 file changed, 30 insertions(+), 77 deletions(-) diff --git a/drivers/mmc/host/rtsx_pci_sdmmc.c b/drivers/mmc/host/rtsx_pci_sdmmc.c index f981f7d..299a27c 100644 --- a/drivers/mmc/host/rtsx_pci_sdmmc.c +++ b/drivers/mmc/host/rtsx_pci_sdmmc.c @@ -32,15 +32,6 @@ #include #include -/* SD Tuning Data Structure - * Record continuous timing phase path - */ -struct timing_phase_path { - int start; - int end; - int mid; - int len; -}; struct realtek_pci_sdmmc { struct platform_device *pdev; @@ -497,85 +488,47 @@ static int sd_change_phase(struct realtek_pci_sdmmc *host, u8 sample_point) return 0; } -static u8 sd_search_final_phase(struct realtek_pci_sdmmc *host, u32 phase_map) +static inline u32 get_phase_point(u32 phase_map, unsigned int idx) { - struct timing_phase_path path[MAX_PHASE + 1]; - int i, j, cont_path_cnt; - int new_block, max_len, final_path_idx; - u8 final_phase = 0xFF; + idx &= MAX_PHASE; + return phase_map & (1 << idx); +} + +static int get_phase_len(u32 phase_map, unsigned int idx) +{ + int i; - /* Parse phase_map, take it as a bit-ring */ - cont_path_cnt = 0; - new_block = 1; - j = 0; for (i = 0; i < MAX_PHASE + 1; i++) { - if (phase_map & (1 << i)) { - if (new_block) { - new_block = 0; - j = cont_path_cnt++; - path[j].start = i; - path[j].end = i; - } else { - path[j].end = i; - } - } else { - new_block = 1; - if (cont_path_cnt) { - /* Calculate path length and middle point */ - int idx = cont_path_cnt - 1; - path[idx].len = - path[idx].end - path[idx].start + 1; - path[idx].mid = - path[idx].start + path[idx].len / 2; - } - } + if (get_phase_point(phase_map, idx + i) == 0) + return i; } + return MAX_PHASE + 1; +} - if (cont_path_cnt == 0) { - dev_dbg(sdmmc_dev(host), "No continuous phase path\n"); - goto finish; - } else { - /* Calculate last continuous path length and middle point */ - int idx = cont_path_cnt - 1; - path[idx].len = path[idx].end - path[idx].start + 1; - path[idx].mid = path[idx].start + path[idx].len / 2; - } +static u8 sd_search_final_phase(struct realtek_pci_sdmmc *host, u32 phase_map) +{ + int start = 0, len = 0; + int start_final = 0, len_final = 0; + u8 final_phase = 0xFF; - /* Connect the first and last continuous paths if they are adjacent */ - if (!path[0].start && (path[cont_path_cnt - 1].end == MAX_PHASE)) { - /* Using negative index */ - path[0].start = path[cont_path_cnt - 1].start - MAX_PHASE - 1; - path[0].len += path[cont_path_cnt - 1].len; - path[0].mid = path[0].start + path[0].len / 2; - /* Convert negative middle point index to positive one */ - if (path[0].mid < 0) - path[0].mid += MAX_PHASE + 1; - cont_path_cnt--; + if (phase_map == 0) { + dev_dbg(sdmmc_dev(host), "Phase: [map:%x]\n", phase_map); + return final_phase; } - /* Choose the longest continuous phase path */ - max_len = 0; - final_phase = 0; - final_path_idx = 0; - for (i = 0; i < cont_path_cnt; i++) { - if (path[i].len > max_len) { - max_len = path[i].len; - final_phase = (u8)path[i].mid; - final_path_idx = i; + while (start < MAX_PHASE + 1) { + len = get_phase_len(phase_map, start); + if (len_final < len) { + start_final = start; + len_final = len; } - - dev_dbg(sdmmc_dev(host), "path[%d].start = %d\n", - i, path[i].start); - dev_dbg(sdmmc_dev(host), "path[%d].end = %d\n", - i, path[i].end); - dev_dbg(sdmmc_dev(host), "path[%d].len = %d\n", - i, path[i].len); - dev_dbg(sdmmc_dev(host), "path[%d].mid = %d\n", - i, path[i].mid); + start += len ? len : 1; } -finish: - dev_dbg(sdmmc_dev(host), "Final chosen phase: %d\n", final_phase); + final_phase = (start_final + len_final / 2) & MAX_PHASE; + dev_dbg(sdmmc_dev(host), "Phase: [map:%x] [maxlen:%d] [final:%d]\n", + phase_map, len_final, final_phase); + return final_phase; } -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/