When using the normal read operation for data transfers, the dummy bus
width is zero. In that case, they are no dummy bytes to transfer and
setting the dummy field in the controller register becomes useless.
Issue was found on a custom "Bifrost" board based on the AST2500 SoC
and using a MX25L51245GMI-08G SPI Flash.
Reported-by: Ian Woloschin <ian.woloschin@akamai.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Tested-by: Ian Woloschin <iwolosch@akamai.com>
Fixes: 9da06d7bde ("spi: aspeed: Add support for direct mapping")
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Link: https://lore.kernel.org/r/20220622161617.3719096-3-clg@kaod.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The default value of the control register is set using the direct
mapping information passed to the ->dirmap_create() handler. Dump the
mapping range and the SPI memory operation characteristics to analyze
how the register value has been computed.
spi-aspeed-smc 1e630000.spi: CE0 read dirmap [ 0x00000000 - 0x04000000 ] OP 0x6c mode:1.1.1.4 naddr:0x4 ndummies:0x1
...
spi-aspeed-smc 1e630000.spi: CE0 write dirmap [ 0x00000000 - 0x04000000 ] OP 0x12 mode:1.1.0.1 naddr:0x4 ndummies:0x0
Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20220622161617.3719096-2-clg@kaod.org
Signed-off-by: Mark Brown <broonie@kernel.org>
In AST2600, the unit of SPI CEx decoding range register is 1MB, and end
address offset is set to the acctual offset - 1MB. If the flash only has
1MB, the end address will has same value as start address, which will
causing unexpected errors.
This patch set the decoding size to at least 2MB to avoid decoding errors.
Tested:
root@bletchley:~# dmesg | grep "aspeed-smc 1e631000.spi: CE0 window"
[ 59.328134] aspeed-smc 1e631000.spi: CE0 window resized to 2MB (AST2600 Decoding)
[ 59.343001] aspeed-smc 1e631000.spi: CE0 window [ 0x50000000 - 0x50200000 ] 2MB
root@bletchley:~# devmem 0x1e631030
0x00100000
Tested-by: Jae Hyun Yoo <quic_jaehyoo@quicinc.com>
Signed-off-by: Potin Lai <potin.lai@quantatw.com>
[ clg : Ported on new spi-mem driver ]
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Link: https://lore.kernel.org/r/20220509175616.1089346-12-clg@kaod.org
Signed-off-by: Mark Brown <broonie@kernel.org>
To accommodate the different response time of SPI transfers on different
boards and different SPI NOR devices, the Aspeed controllers provide a
set of Read Timing Compensation registers to tune the timing delays
depending on the frequency being used. The AST2600 SoC has one of these
registers per device. On the AST2500 and AST2400 SoCs, the timing
register is shared by all devices which is problematic to get good
results other than for one device.
The algorithm first reads a golden buffer at low speed and then performs
reads with different clocks and delay cycle settings to find a breaking
point. This selects a default good frequency for the CEx control register.
The current settings are a bit optimistic as we pick the first delay giving
good results. A safer approach would be to determine an interval and
choose the middle value.
Calibration is performed when the direct mapping for reads is created.
Since the underlying spi-nor object needs to be initialized to create
the spi_mem operation for direct mapping, we should be fine. Having a
specific API would clarify the requirements though.
Cc: Pratyush Yadav <p.yadav@ti.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Tested-by: Joel Stanley <joel@jms.id.au>
Tested-by: Tao Ren <rentao.bupt@gmail.com>
Tested-by: Jae Hyun Yoo <quic_jaehyoo@quicinc.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Link: https://lore.kernel.org/r/20220509175616.1089346-9-clg@kaod.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Extend the driver for the AST2400 SPI Flash Controller (SPI). This
controller has a slightly different interface which requires
adaptation of the 4B handling. Summary of features :
. host Firmware
. 1 chip select pin (CE0)
. slightly different register set, between AST2500 and the legacy
controller
. no segment registers
. single, dual mode.
Reviewed-by: Joel Stanley <joel@jms.id.au>
Tested-by: Joel Stanley <joel@jms.id.au>
Tested-by: Tao Ren <rentao.bupt@gmail.com>
Tested-by: Jae Hyun Yoo <quic_jaehyoo@quicinc.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Link: https://lore.kernel.org/r/20220509175616.1089346-8-clg@kaod.org
Signed-off-by: Mark Brown <broonie@kernel.org>
It is not possible to configure a full 128MB window for a chip of the
same size on the AST2500 SPI controller. For this case, the maximum
window size is restricted to 120MB for CE0.
Reviewed-by: Joel Stanley <joel@jms.id.au>
Tested-by: Joel Stanley <joel@jms.id.au>
Tested-by: Tao Ren <rentao.bupt@gmail.com>
Tested-by: Jae Hyun Yoo <quic_jaehyoo@quicinc.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Link: https://lore.kernel.org/r/20220509175616.1089346-7-clg@kaod.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The segment registers of the FMC/SPI controllers provide a way to
configure the mapping window of the flash device contents on the AHB
bus. Adjust this window to the size of the spi-mem mapping.
Things get more complex with multiple devices. The driver needs to
also adjust the window of the next device to make sure that there is
no overlap, even if there is no available device. The proposal below
is not perfect but it is covering all the cases we have seen on
different boards with one and two devices on the same bus.
Reviewed-by: Joel Stanley <joel@jms.id.au>
Tested-by: Joel Stanley <joel@jms.id.au>
Tested-by: Tao Ren <rentao.bupt@gmail.com>
Tested-by: Jae Hyun Yoo <quic_jaehyoo@quicinc.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Link: https://lore.kernel.org/r/20220509175616.1089346-6-clg@kaod.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Use direct mapping to read the flash device contents. This operation
mode is called "Command mode" on Aspeed SoC SMC controllers. It uses a
Control Register for the settings to apply when a memory operation is
performed on the flash device mapping window.
If the window is not big enough, fall back to the "User mode" to
perform the read.
Direct mapping for writes will come later when validated.
Reviewed-by: Joel Stanley <joel@jms.id.au>
Tested-by: Joel Stanley <joel@jms.id.au>
Tested-by: Tao Ren <rentao.bupt@gmail.com>
Tested-by: Jae Hyun Yoo <quic_jaehyoo@quicinc.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Link: https://lore.kernel.org/r/20220509175616.1089346-5-clg@kaod.org
Signed-off-by: Mark Brown <broonie@kernel.org>
This SPI driver adds support for the Aspeed static memory controllers
of the AST2600, AST2500 and AST2400 SoCs using the spi-mem interface.
* AST2600 Firmware SPI Memory Controller (FMC)
. BMC firmware
. 3 chip select pins (CE0 ~ CE2)
. Only supports SPI type flash memory
. different segment register interface
. single, dual and quad mode.
* AST2600 SPI Flash Controller (SPI1 and SPI2)
. host firmware
. 2 chip select pins (CE0 ~ CE1)
. different segment register interface
. single, dual and quad mode.
* AST2500 Firmware SPI Memory Controller (FMC)
. BMC firmware
. 3 chip select pins (CE0 ~ CE2)
. supports SPI type flash memory (CE0-CE1)
. CE2 can be of NOR type flash but this is not supported by the driver
. single, dual mode.
* AST2500 SPI Flash Controller (SPI1 and SPI2)
. host firmware
. 2 chip select pins (CE0 ~ CE1)
. single, dual mode.
* AST2400 New Static Memory Controller (also referred as FMC)
. BMC firmware
. New register set
. 5 chip select pins (CE0 ∼ CE4)
. supports NOR flash, NAND flash and SPI flash memory.
. single, dual and quad mode.
Each controller has a memory range on which flash devices contents are
mapped. Each device is assigned a window that can be changed at bootime
with the Segment Address Registers.
Each SPI flash device can then be accessed in two modes: Command and
User. When in User mode, SPI transfers are initiated with accesses to
the memory segment of a device. When in Command mode, memory
operations on the memory segment of a device generate SPI commands
automatically using a Control Register for the settings.
This initial patch adds support for User mode. Command mode needs a little
more work to check that the memory window on the AHB bus fits the device
size. It will come later when support for direct mapping is added.
Single and dual mode RX transfers are supported. Other types than SPI
are not supported.
Reviewed-by: Joel Stanley <joel@jms.id.au>
Tested-by: Joel Stanley <joel@jms.id.au>
Tested-by: Tao Ren <rentao.bupt@gmail.com>
Tested-by: Jae Hyun Yoo <quic_jaehyoo@quicinc.com>
Signed-off-by: Chin-Ting Kuo <chin-ting_kuo@aspeedtech.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Link: https://lore.kernel.org/r/20220509175616.1089346-4-clg@kaod.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Cédric Le Goater