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| author | Rafał Miłecki <zajec5@gmail.com> | 2016-04-26 09:23:12 +0000 |
|---|---|---|
| committer | Rafał Miłecki <zajec5@gmail.com> | 2016-04-26 09:23:12 +0000 |
| commit | 08fe019a4c3dee78a885f0d92287c94e8ec9f6a1 (patch) | |
| tree | a428bde19f647a9ce72ca00249dbbda1bb1b6103 /target/linux/generic/patches-4.4/045-mtd-devices-m25p80-add-support-for-mmap-read-request.patch | |
| parent | 3f91c5fd81050fddcb205762afd9635ae7d09953 (diff) | |
| download | master-187ad058-08fe019a4c3dee78a885f0d92287c94e8ec9f6a1.tar.gz master-187ad058-08fe019a4c3dee78a885f0d92287c94e8ec9f6a1.tar.bz2 master-187ad058-08fe019a4c3dee78a885f0d92287c94e8ec9f6a1.zip | |
kernel: backport support for accelerated SPI flash read
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@49233 3c298f89-4303-0410-b956-a3cf2f4a3e73
Diffstat (limited to 'target/linux/generic/patches-4.4/045-mtd-devices-m25p80-add-support-for-mmap-read-request.patch')
| -rw-r--r-- | target/linux/generic/patches-4.4/045-mtd-devices-m25p80-add-support-for-mmap-read-request.patch | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/target/linux/generic/patches-4.4/045-mtd-devices-m25p80-add-support-for-mmap-read-request.patch b/target/linux/generic/patches-4.4/045-mtd-devices-m25p80-add-support-for-mmap-read-request.patch new file mode 100644 index 0000000000..ee85f448ff --- /dev/null +++ b/target/linux/generic/patches-4.4/045-mtd-devices-m25p80-add-support-for-mmap-read-request.patch @@ -0,0 +1,46 @@ +From 08922f644878c9163ada8df3ef9def89be1d5e90 Mon Sep 17 00:00:00 2001 +From: Vignesh R <vigneshr@ti.com> +Date: Tue, 29 Mar 2016 11:16:17 +0530 +Subject: [PATCH] mtd: devices: m25p80: add support for mmap read request + +Certain SPI controllers may provide accelerated hardware interface to +read from m25p80 type flash devices in order to provide better read +performance. SPI core supports such devices with spi_flash_read() API. +Call spi_flash_read(), if supported, to make use of such interface. + +Signed-off-by: Vignesh R <vigneshr@ti.com> +[Brian: add memset()] +Signed-off-by: Brian Norris <computersforpeace@gmail.com> +--- + +--- a/drivers/mtd/devices/m25p80.c ++++ b/drivers/mtd/devices/m25p80.c +@@ -131,6 +131,28 @@ static int m25p80_read(struct spi_nor *nor, loff_t from, size_t len, + /* convert the dummy cycles to the number of bytes */ + dummy /= 8; + ++ if (spi_flash_read_supported(spi)) { ++ struct spi_flash_read_message msg; ++ int ret; ++ ++ memset(&msg, 0, sizeof(msg)); ++ ++ msg.buf = buf; ++ msg.from = from; ++ msg.len = len; ++ msg.read_opcode = nor->read_opcode; ++ msg.addr_width = nor->addr_width; ++ msg.dummy_bytes = dummy; ++ /* TODO: Support other combinations */ ++ msg.opcode_nbits = SPI_NBITS_SINGLE; ++ msg.addr_nbits = SPI_NBITS_SINGLE; ++ msg.data_nbits = m25p80_rx_nbits(nor); ++ ++ ret = spi_flash_read(spi, &msg); ++ *retlen = msg.retlen; ++ return ret; ++ } ++ + spi_message_init(&m); + memset(t, 0, (sizeof t)); + |