mail archive of the barebox mailing list
 help / color / mirror / Atom feed
From: Ahmad Fatoum <a.fatoum@pengutronix.de>
To: barebox@lists.infradead.org
Cc: Sam Ravnborg <sam@ravnborg.org>, Ahmad Fatoum <a.fatoum@pengutronix.de>
Subject: [PATCH v4 02/14] mci: atmel_mci: fix zeroing of block length on AT91SAM9263
Date: Tue, 20 Feb 2024 10:30:48 +0100	[thread overview]
Message-ID: <20240220093100.1539120-3-a.fatoum@pengutronix.de> (raw)
In-Reply-To: <20240220093100.1539120-1-a.fatoum@pengutronix.de>

We don't read back ATMCI_MR, but instead set up the value once and keep
writing it on every reset. On the SAM9263, but not on the later SAM9x5,
the ATMCI_MR register also includes a field for the block length. Not
taking that into account means that we zero the block length on every
reset.

While the effect of this zeroing is likely limited, because we set the
block length on every transfer via ATMCI_BLKR, it would be less surprising
and more robust against future change to not intermittently zero the block
length via the MR register.

Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 drivers/mci/atmel_mci_common.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/mci/atmel_mci_common.c b/drivers/mci/atmel_mci_common.c
index 098e90503a3a..7b11e9134e65 100644
--- a/drivers/mci/atmel_mci_common.c
+++ b/drivers/mci/atmel_mci_common.c
@@ -68,7 +68,17 @@ static void atmci_set_clk_rate(struct atmel_mci *host,
 				 clock_min, host->bus_hz / (2 * 256));
 			clkdiv = 255;
 		}
-		host->mode_reg = ATMCI_MR_CLKDIV(clkdiv);
+
+		/*
+		 * Older Atmels without CLKODD have the block length
+		 * in the upper 16 bits of both MCI_MR and MCI_BLKR
+		 *
+		 * To avoid intermittent zeroing of the block length,
+		 * just hardcode 512 here and have atmci_setup_data()
+		 * change it as necessary.
+		 */
+
+		host->mode_reg = ATMCI_MR_CLKDIV(clkdiv) | ATMCI_BLKLEN(512);
 	}
 
 	dev_dbg(host->hw_dev, "atmel_set_clk_rate: clkIn=%ld clkIos=%d divider=%d\n",
-- 
2.39.2




  parent reply	other threads:[~2024-02-20  9:32 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-02-20  9:30 [PATCH v4 00/14] ARM: at91: skov-arm9cpu (SAM9263) first stage support Ahmad Fatoum
2024-02-20  9:30 ` [PATCH v4 01/14] mci: atmel_mci: disable power save mode Ahmad Fatoum
2024-02-20  9:30 ` Ahmad Fatoum [this message]
2024-02-20  9:30 ` [PATCH v4 03/14] ARM: replace ENTRY_FUNCTION_HEAD with ENTRY_FUNCTION_WITHSTACK_HEAD Ahmad Fatoum
2024-02-20  9:30 ` [PATCH v4 04/14] ARM: at91: use AT91 header instead of generic barebox ARM's Ahmad Fatoum
2024-02-20  9:30 ` [PATCH v4 05/14] ARM: at91: implement SAM9_ENTRY_FUNCTION Ahmad Fatoum
2024-02-20  9:30 ` [PATCH v4 06/14] ARM: at91: sam9263_ll: drop PLL charge pump initialization Ahmad Fatoum
2024-02-20  9:30 ` [PATCH v4 07/14] ARM: at91: sam9263_ll: pass AT91_PMC_LL_AT91SAM9263 to PMC functions Ahmad Fatoum
2024-02-20  9:30 ` [PATCH v4 08/14] ARM: at91: sam9263_ll: refactor MCK switch to PLLA for clarity Ahmad Fatoum
2024-02-20  9:30 ` [PATCH v4 09/14] ARM: at91: sam9263_ll: support configuration of PLLB Ahmad Fatoum
2024-02-20  9:30 ` [PATCH v4 10/14] ARM: dts: AT91: skov-arm9cpu: remove barebox environment on NOR Ahmad Fatoum
2024-02-20  9:30 ` [PATCH v4 11/14] ARM: at91: skov-arm9cpu: Add SD-Card xload support Ahmad Fatoum
2024-02-20  9:30 ` [PATCH v4 12/14] ARM: at91: skov-arm9cpu: configure SMC for NOR flash use Ahmad Fatoum
2024-02-20  9:30 ` [PATCH v4 13/14] ARM: at91: skov-arm9cpu: configure more appropriate hostname Ahmad Fatoum
2024-02-20  9:31 ` [PATCH v4 14/14] ARM: AT91: skov-arm9cpu: support environment on SD-Card Ahmad Fatoum
2024-02-23  7:32 ` [PATCH v4 00/14] ARM: at91: skov-arm9cpu (SAM9263) first stage support Sascha Hauer

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20240220093100.1539120-3-a.fatoum@pengutronix.de \
    --to=a.fatoum@pengutronix.de \
    --cc=barebox@lists.infradead.org \
    --cc=sam@ravnborg.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox