From: Krishna Yarlagadda <kyarlagadda@nvidia.com>
To: <broonie@kernel.org>, <thierry.reding@gmail.com>,
<jonathanh@nvidia.com>, <linux-spi@vger.kernel.org>,
<linux-tegra@vger.kernel.org>
Cc: <skomatineni@nvidia.com>, <ldewangan@nvidia.com>,
<linux-kernel@vger.kernel.org>,
Krishna Yarlagadda <kyarlagadda@nvidia.com>
Subject: [PATCH 4/5] spi: tegra210-quad: combined seq for 4READ
Date: Sat, 1 Oct 2022 17:51:47 +0530 [thread overview]
Message-ID: <20221001122148.9158-4-kyarlagadda@nvidia.com> (raw)
In-Reply-To: <20221001122148.9158-1-kyarlagadda@nvidia.com>
X2 and X4 reads require dummy cycles. Use hardware dummy clock cycles
programming to use combined sequence for X2, X4 transfers as well.
Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
---
drivers/spi/spi-tegra210-quad.c | 22 +++++++++++++++++++---
1 file changed, 19 insertions(+), 3 deletions(-)
diff --git a/drivers/spi/spi-tegra210-quad.c b/drivers/spi/spi-tegra210-quad.c
index be11daafb7d4..99811509dafa 100644
--- a/drivers/spi/spi-tegra210-quad.c
+++ b/drivers/spi/spi-tegra210-quad.c
@@ -159,7 +159,8 @@
#define DEFAULT_QSPI_DMA_BUF_LEN (64 * 1024)
#define CMD_TRANSFER 0
#define ADDR_TRANSFER 1
-#define DATA_TRANSFER 2
+#define DUMMY_TRANSFER 2
+#define DATA_TRANSFER 3
struct tegra_qspi_soc_data {
bool has_dma;
@@ -1072,7 +1073,12 @@ static int tegra_qspi_combined_seq_xfer(struct tegra_qspi *tqspi,
xfer->len);
address_value = *((const u32 *)(xfer->tx_buf));
break;
+ case DUMMY_TRANSFER:
case DATA_TRANSFER:
+ if (xfer->dummy_data) {
+ tqspi->dummy_cycles = xfer->len * 8 / xfer->tx_nbits;
+ break;
+ }
/* Program Command, Address value in register */
tegra_qspi_writel(tqspi, cmd_value, QSPI_CMB_SEQ_CMD);
tegra_qspi_writel(tqspi, address_value,
@@ -1277,7 +1283,9 @@ static bool tegra_qspi_validate_cmb_seq(struct tegra_qspi *tqspi,
list_for_each_entry(xfer, &msg->transfers, transfer_list) {
transfer_count++;
}
- if (!tqspi->soc_data->cmb_xfer_capable || transfer_count != 3)
+ if (!tqspi->soc_data->cmb_xfer_capable)
+ return false;
+ if (transfer_count > 4 || transfer_count < 3)
return false;
xfer = list_first_entry(&msg->transfers, typeof(*xfer),
transfer_list);
@@ -1287,7 +1295,15 @@ static bool tegra_qspi_validate_cmb_seq(struct tegra_qspi *tqspi,
if (xfer->len > 4 || xfer->len < 3)
return false;
xfer = list_next_entry(xfer, transfer_list);
- if (!tqspi->soc_data->has_dma || xfer->len > (QSPI_FIFO_DEPTH << 2))
+ if (transfer_count == 4) {
+ if (xfer->dummy_data != 1)
+ return false;
+ if ((xfer->len * 8 / xfer->tx_nbits) >
+ QSPI_DUMMY_CYCLES_MAX)
+ return false;
+ xfer = list_next_entry(xfer, transfer_list);
+ }
+ if (!tqspi->soc_data->has_dma && xfer->len > (QSPI_FIFO_DEPTH << 2))
return false;
return true;
--
2.17.1
next prev parent reply other threads:[~2022-10-01 12:22 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-01 12:21 [PATCH 1/5] spi: tegra210-quad: Fix combined sequence Krishna Yarlagadda
2022-10-01 12:21 ` [PATCH 2/5] spi: tegra210-quad: Fix duplicate resource error Krishna Yarlagadda
2022-11-11 9:49 ` Jon Hunter
2022-10-01 12:21 ` [PATCH 3/5] spi: tegra210-quad: Use nbits in combined seq Krishna Yarlagadda
2022-10-03 15:24 ` Mark Brown
2022-10-01 12:21 ` Krishna Yarlagadda [this message]
2022-10-01 12:21 ` [PATCH 5/5] spi: tegra210-quad: native dma support Krishna Yarlagadda
2022-10-01 20:08 ` kernel test robot
2022-10-01 20:50 ` kernel test robot
2022-10-02 10:37 ` Geert Uytterhoeven
2022-10-03 16:47 ` (subset) [PATCH 1/5] spi: tegra210-quad: Fix combined sequence Mark Brown
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=20221001122148.9158-4-kyarlagadda@nvidia.com \
--to=kyarlagadda@nvidia.com \
--cc=broonie@kernel.org \
--cc=jonathanh@nvidia.com \
--cc=ldewangan@nvidia.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-spi@vger.kernel.org \
--cc=linux-tegra@vger.kernel.org \
--cc=skomatineni@nvidia.com \
--cc=thierry.reding@gmail.com \
/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;
as well as URLs for NNTP newsgroup(s).