[src/trunk]: src/sys/dev/sdmmc If setting HS_TIMING fails, keep trying slower...

[jmcneill <jmcneill%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/a19269628b18
branches:  trunk
changeset: 457014:a19269628b18
user:      jmcneill <jmcneill%NetBSD.org@localhost>
date:      Thu Jun 06 20:50:46 2019 +0000

description:
If setting HS_TIMING fails, keep trying slower speeds instead of bailing
out.

diffstat:

 sys/dev/sdmmc/sdmmc_mem.c |  37 ++++++++++++++++++++++++-------------
 1 files changed, 24 insertions(+), 13 deletions(-)

diffs (83 lines):

diff -r 99ede378a25b -r a19269628b18 sys/dev/sdmmc/sdmmc_mem.c
--- a/sys/dev/sdmmc/sdmmc_mem.c Thu Jun 06 20:45:35 2019 +0000
+++ b/sys/dev/sdmmc/sdmmc_mem.c Thu Jun 06 20:50:46 2019 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: sdmmc_mem.c,v 1.67 2019/05/28 00:25:27 jmcneill Exp $  */
+/*     $NetBSD: sdmmc_mem.c,v 1.68 2019/06/06 20:50:46 jmcneill Exp $  */
 /*     $OpenBSD: sdmmc_mem.c,v 1.10 2009/01/09 10:55:22 jsg Exp $      */
 
 /*
@@ -45,7 +45,7 @@
 /* Routines for SD/MMC memory cards. */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: sdmmc_mem.c,v 1.67 2019/05/28 00:25:27 jmcneill Exp $");
+__KERNEL_RCSID(0, "$NetBSD: sdmmc_mem.c,v 1.68 2019/06/06 20:50:46 jmcneill Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_sdmmc.h"
@@ -124,6 +124,12 @@
        { "DDR50",              SMC_CAPS_UHS_DDR50,      50000 },
 };
 
+static const int sdmmc_mmc_timings[] = {
+       [EXT_CSD_HS_TIMING_LEGACY]      = 26000,
+       [EXT_CSD_HS_TIMING_HIGHSPEED]   = 52000,
+       [EXT_CSD_HS_TIMING_HS200]       = 200000
+};
+
 /*
  * Initialize SD/MMC memory cards and memory in SDIO "combo" cards.
  */
@@ -955,18 +961,14 @@
 
                if (ISSET(sc->sc_caps, SMC_CAPS_MMC_HS200) &&
                    ext_csd[EXT_CSD_CARD_TYPE] & EXT_CSD_CARD_TYPE_F_HS200_1_8V) {
-                       sf->csd.tran_speed = 200000;    /* 200MHz SDR */
                        hs_timing = EXT_CSD_HS_TIMING_HS200;
                } else if (ISSET(sc->sc_caps, SMC_CAPS_MMC_DDR52) &&
                    ext_csd[EXT_CSD_CARD_TYPE] & EXT_CSD_CARD_TYPE_F_DDR52_1_8V) {
-                       sf->csd.tran_speed = 52000;     /* 52MHz */
                        hs_timing = EXT_CSD_HS_TIMING_HIGHSPEED;
                        ddr = true;
                } else if (ext_csd[EXT_CSD_CARD_TYPE] & EXT_CSD_CARD_TYPE_F_52M) {
-                       sf->csd.tran_speed = 52000;     /* 52MHz */
                        hs_timing = EXT_CSD_HS_TIMING_HIGHSPEED;
                } else if (ext_csd[EXT_CSD_CARD_TYPE] & EXT_CSD_CARD_TYPE_F_26M) {
-                       sf->csd.tran_speed = 26000;     /* 26MHz */
                        hs_timing = EXT_CSD_HS_TIMING_LEGACY;
                } else {
                        aprint_error_dev(sc->sc_dev,
@@ -1007,16 +1009,25 @@
                    !ISSET(sc->sc_caps, SMC_CAPS_MMC_HIGHSPEED)) {
                        hs_timing = EXT_CSD_HS_TIMING_LEGACY;
                }
+
+               const int target_timing = hs_timing;
                if (hs_timing != EXT_CSD_HS_TIMING_LEGACY) {
-                       error = sdmmc_mem_mmc_switch(sf, EXT_CSD_CMD_SET_NORMAL,
-                           EXT_CSD_HS_TIMING, hs_timing, false);
-                       if (error) {
-                               aprint_error_dev(sc->sc_dev,
-                                   "can't change high speed %d, error %d\n",
-                                   hs_timing, error);
-                               return error;
+                       while (hs_timing >= EXT_CSD_HS_TIMING_LEGACY) {
+                               error = sdmmc_mem_mmc_switch(sf, EXT_CSD_CMD_SET_NORMAL,
+                                   EXT_CSD_HS_TIMING, hs_timing, false);
+                               if (error == 0 || hs_timing == EXT_CSD_HS_TIMING_LEGACY)
+                                       break;
+                               hs_timing--;
                        }
                }
+               if (hs_timing != target_timing) {
+                       aprint_debug_dev(sc->sc_dev,
+                           "card failed to switch to timing mode %d, using %d\n",
+                           target_timing, hs_timing);
+               }
+
+               KASSERT(hs_timing < __arraycount(sdmmc_mmc_timings));
+               sf->csd.tran_speed = sdmmc_mmc_timings[hs_timing];
 
                if (sc->sc_busclk > sf->csd.tran_speed)
                        sc->sc_busclk = sf->csd.tran_speed;