Use the newly introduced spi_mem_dtr_supports_op() to check DTR op
support. This means the buswidth check does not need to be replicated.
It also happens to fix a bug where STR ops with a 2-byte opcode would be
reported as supported.
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20210204141218.32229-2-p.yadav@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The kernel test robot reports the following warning.
drivers/spi/spi-cadence-quadspi.c:966:24: warning: comparison of distinct pointer types ('typeof (len) *' (aka 'unsigned int *') and 'typeof (500UL) *' (aka 'unsigned long *')) [-Wcompare-distinct-pointer-types]
msecs_to_jiffies(max(len, 500UL)))) {
^~~~~~~~~~~~~~~
include/linux/minmax.h:58:19: note: expanded from macro 'max'
#define max(x, y) __careful_cmp(x, y, >)
^~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:42:24: note: expanded from macro '__careful_cmp'
__builtin_choose_expr(__safe_cmp(x, y), \
^~~~~~~~~~~~~~~~
include/linux/minmax.h:32:4: note: expanded from macro '__safe_cmp'
(__typecheck(x, y) && __no_side_effects(x, y))
^~~~~~~~~~~~~~~~~
include/linux/minmax.h:18:28: note: expanded from macro '__typecheck'
(!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~
1 warning generated.
This happens because size_t is unsigned long on 64-bit platforms like
arm64 but it is unsigned int on 32-bit platforms like arm. Omitting the
"UL" would result in a warning on 64-bit platforms. Squash it by type
casting the arguments to size_t using max_t(). This way builds on both
type of platforms can be satisfied. There is no chance of any truncation
since 500 is small enough to fit into both int and long.
Fixes: f453f29397 ("spi: cadence-quadspi: Wait at least 500 ms for direct reads")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20210108181457.30291-1-p.yadav@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Fix a new warning report by build for make ARCH=MIPS allmodconfig:
drivers/spi/spi-cadence-quadspi.c: In function 'cqspi_direct_read_execute':
./include/linux/minmax.h:18:28: warning: comparison of distinct pointer types lacks a cast
18 | (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
| ^~
./include/linux/minmax.h:32:4: note: in expansion of macro '__typecheck'
32 | (__typecheck(x, y) && __no_side_effects(x, y))
| ^~~~~~~~~~~
./include/linux/minmax.h:42:24: note: in expansion of macro '__safe_cmp'
42 | __builtin_choose_expr(__safe_cmp(x, y), \
| ^~~~~~~~~~
./include/linux/minmax.h:58:19: note: in expansion of macro '__careful_cmp'
58 | #define max(x, y) __careful_cmp(x, y, >)
| ^~~~~~~~~~~~~
drivers/spi/spi-cadence-quadspi.c:1153:24: note: in expansion of macro 'max'
1153 | msecs_to_jiffies(max(len, 500UL)))) {
| ^~~
"len" is unsigned,however,"500" is unsigned long.
Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Link: https://lore.kernel.org/r/20210107115704.3835282-1-siyanteng@loongson.cn
Signed-off-by: Mark Brown <broonie@kernel.org>
Double Transfer Rate (DTR) mode transfers data twice per clock cycle.
Add support for parsing DTR ops and set up the registers to allow it.
Most SPI NOR flashes expect 2 byte commands. Parse the 2-byte opcode
from SPI MEM and set it up in the CQSPI_REG_OP_EXT_LOWER register.
Increment the delay needed before issuing indirect writes because larger
delay is needed for DTR mode. With the current delay some writes end up
missing.
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20201222184425.7028-8-p.yadav@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
When performing a direct read via DMA the timeout for completion is set
equal to the read length. This is fine for larger reads. For a small
read like the Read Status Register command, the timeout would be 1 or 2
milliseconds. This is not enough to cover the overhead needed in setting
up DMA.
Make sure the timeout is at least 500 ms to allow DMA ample time to
finish. For reads larger than 500 bytes, the timeout will continue to be
equal to the read length.
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/r/20201222184425.7028-7-p.yadav@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
SPI MEM deals with dummy bytes but the controller deals with dummy
cycles. Multiplying bytes by 8 is correct if the dummy phase uses 1S
mode since 1 byte will be sent in 8 cycles. But if the dummy phase uses
4S mode then 1 byte will be sent in 2 cycles.
To correctly translate dummy bytes to dummy cycles, the dummy buswidth
also needs to be taken into account. Divide 8 by the buswidth to get the
correct multiplier for getting the number of cycles.
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20201222184425.7028-5-p.yadav@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
If a command does not have an address phase it goes via the STIG path.
The dummy cycles are not initialized for the STIG commands. As a result,
STIG commands with dummy cycles will not work.
Initialize the dummy cycle field before issuing the STIG command to make
sure it is sent correctly. Move the code to calculate dummy cycle value
to a separate function so it is not repeated twice. DTR support will add
some more logic here to it is worth it to extract it out in a function.
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20201222184425.7028-4-p.yadav@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The controller can only support up to 31 dummy cycles. If the command
requires more it falls back to using 31. This command is likely to fail
because the correct number of cycles are not waited upon. Rather than
silently issuing an incorrect command, fail loudly so the caller can get
a chance to find out the command can't be supported by the controller.
Fixes: 1406234105 ("mtd: spi-nor: Add driver for Cadence Quad SPI Flash Controller")
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20201222184425.7028-3-p.yadav@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
As of commit 9326e4f1e5 ("spi: Limit the spi device max speed to
controller's max speed"), the SPI device max speed is set to the
controller's max speed if it is larger. The Cadence QSPI controller does
not set the controller's max speed so it is left at its initial value of
0. This means the SPI device max speed is always set to 0.
The SPI device max speed is used to calculate the baud rate divider when
performing an operation. If this speed is 0, the default divider of 32
is used. No matter what speed is specified by the device tree property
'spi-max-frequency', the device will always operate at ref_clk / 32.
Fix this by setting master->max_speed_hz to the ref clock speed so the
correct divider can be calculated.
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20201222184425.7028-2-p.yadav@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Buffers need to mapped to DMA channel's device pointer instead of SPI
controller's device pointer as its system DMA that actually does data
transfer.
Data inconsistencies have been reported when reading from flash
without this fix.
Fixes: ffa639e069 ("mtd: spi-nor: cadence-quadspi: Add DMA support for direct mode reads")
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Tested-by: Jan Kiszka <jan.kiszka@siemens.com>
Link: https://lore.kernel.org/r/20200831130720.4524-1-vigneshr@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
