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From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <zajec5@gmail.com>
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Subject: [PATCH] mtd: m25p80: use single SPI message for writing data
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MIME-Version: 1.0
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Content-Type: text/plain; charset=UTF-8
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Content-Transfer-Encoding: 8bit
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On all 3 tested Northstar devices with following flash memories:
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mx25l6405d (8192 Kbytes)
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mx25l12805d (16384 Kbytes)
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mx25l25635e (32768 Kbytes)
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I noticed writing to be broken. Not a single bit was changed leaving all
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bytes set to 0xff.
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This is most likely some problem related to the SPI controller or its
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driver. Using a single SPI message seems to workaround this. Of course
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it's not perfect solution as copying whole data into a new buffer makes
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writing slower.
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Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
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---
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--- a/drivers/mtd/devices/m25p80.c
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+++ b/drivers/mtd/devices/m25p80.c
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@@ -78,29 +78,30 @@ static void m25p80_write(struct spi_nor
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{
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struct m25p *flash = nor->priv;
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struct spi_device *spi = flash->spi;
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+ u8 *command = kzalloc(MAX_CMD_SIZE + len, GFP_KERNEL);
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struct spi_transfer t[2] = {};
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struct spi_message m;
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int cmd_sz = m25p_cmdsz(nor);
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+ int i;
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spi_message_init(&m);
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if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
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cmd_sz = 1;
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- flash->command[0] = nor->program_opcode;
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- m25p_addr2cmd(nor, to, flash->command);
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+ command[0] = nor->program_opcode;
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+ m25p_addr2cmd(nor, to, command);
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+ memcpy(&command[cmd_sz], buf, len);
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- t[0].tx_buf = flash->command;
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- t[0].len = cmd_sz;
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+ t[0].tx_buf = command;
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+ t[0].len = cmd_sz + len;
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spi_message_add_tail(&t[0], &m);
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- t[1].tx_buf = buf;
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- t[1].len = len;
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- spi_message_add_tail(&t[1], &m);
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-
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spi_sync(spi, &m);
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*retlen += m.actual_length - cmd_sz;
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+
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+ kfree(command);
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}
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static inline unsigned int m25p80_rx_nbits(struct spi_nor *nor)
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