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mmc: sdhci-of-dwcmshc: th1520: Increase tuning loop count to 128

PATCH In review Maksim Kiselev 3 participants 3 messages Apr 2, 2024 – Apr 4, 2024

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#0 lore raw

PATCH 1/1 mmc: sdhci-of-dwcmshc: th1520: Increase tuning loop count to 128

Fix SD card tuning error by increasing tuning loop count from 40(MAX_TUNING_LOOP) to 128.

For some reason the tuning algorithm requires to move through all the taps of delay line even if the THRESHOLD_MODE (bit 2 in AT_CTRL_R) is used instead of the LARGEST_WIN_MODE.

---
Previous discussion was here:
https://lore.kernel.org/lkml/CALHCpMhc1F5Ue7U_gsDXREHUZRVQJNYRCJxYxoNqbN=-39jf7A@mail.gmail.com/

 drivers/mmc/host/sdhci-of-dwcmshc.c | 1 +
 1 file changed, 1 insertion(+)
drivers/mmc/host/sdhci-of-dwcmshc.c +1 -0
index 8d6cfb648096..1001b6ea1a89 100644
@@ -706,6 +706,7 @@ static int th1520_execute_tuning(struct sdhci_host *host, u32 opcode)
 
 	/* perform tuning */
 	sdhci_start_tuning(host);
+	host->tuning_loop_count = 128;
 	host->tuning_err = __sdhci_execute_tuning(host, opcode);
 	if (host->tuning_err) {
 		/* disable auto-tuning upon tuning error */
Signature · 1 line
2.40.1
maintainer Acked-by on v1 1/1
#1 lore raw
Quoted 10 lines · Maksim Kiselev

Fix SD card tuning error by increasing tuning loop count from 40(MAX_TUNING_LOOP) to 128.

For some reason the tuning algorithm requires to move through all the taps of delay line even if the THRESHOLD_MODE (bit 2 in AT_CTRL_R) is used instead of the LARGEST_WIN_MODE.

Quoted 19 lines

---
Previous discussion was here:
https://lore.kernel.org/lkml/CALHCpMhc1F5Ue7U_gsDXREHUZRVQJNYRCJxYxoNqbN=-39jf7A@mail.gmail.com/

 drivers/mmc/host/sdhci-of-dwcmshc.c | 1 +
 1 file changed, 1 insertion(+)
drivers/mmc/host/sdhci-of-dwcmshc.c +1 -0
index 8d6cfb648096..1001b6ea1a89 100644
@@ -706,6 +706,7 @@ static int th1520_execute_tuning(struct sdhci_host *host, u32 opcode)
 
 	/* perform tuning */
 	sdhci_start_tuning(host);
+	host->tuning_loop_count = 128;
 	host->tuning_err = __sdhci_execute_tuning(host, opcode);
 	if (host->tuning_err) {
 		/* disable auto-tuning upon tuning error */
#2 lore raw
In reply to Maksim Kiselev
Quoted 11 lines · Maksim Kiselev

Fix SD card tuning error by increasing tuning loop count from 40(MAX_TUNING_LOOP) to 128.

For some reason the tuning algorithm requires to move through all the taps of delay line even if the THRESHOLD_MODE (bit 2 in AT_CTRL_R) is used instead of the LARGEST_WIN_MODE.

Applied for fixes and by adding a fixes+stable tag, thanks!

Kind regards
Uffe

Quoted 22 lines

---
Previous discussion was here:
https://lore.kernel.org/lkml/CALHCpMhc1F5Ue7U_gsDXREHUZRVQJNYRCJxYxoNqbN=-39jf7A@mail.gmail.com/

 drivers/mmc/host/sdhci-of-dwcmshc.c | 1 +
 1 file changed, 1 insertion(+)
drivers/mmc/host/sdhci-of-dwcmshc.c +1 -1
index 8d6cfb648096..1001b6ea1a89 100644
@@ -706,6 +706,7 @@ static int th1520_execute_tuning(struct sdhci_host *host, u32 opcode)
 
        /* perform tuning */
        sdhci_start_tuning(host);
+       host->tuning_loop_count = 128;
        host->tuning_err = __sdhci_execute_tuning(host, opcode);
        if (host->tuning_err) {
                /* disable auto-tuning upon tuning error */
--

2.40.1