diff options
| author | Serge Semin <Sergey.Semin@baikalelectronics.ru> | 2020-10-08 02:55:10 +0300 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2020-10-08 23:00:22 +0100 |
| commit | abf00907538e21c469a10809dc2991982673fcbf (patch) | |
| tree | 573f5473602b4009463f8bad424dbd3d899173ce /drivers/spi/Kconfig | |
| parent | 14345c33461bc2373bc4f75f40baf4650e95ee54 (diff) | |
spi: dw: Add Baikal-T1 SPI Controller glue driver
Baikal-T1 is equipped with three DW APB SSI-based MMIO SPI controllers.
Two of them are pretty much normal: with IRQ, DMA, FIFOs of 64 words
depth, 4x CSs, but the third one as being a part of the Baikal-T1 System
Boot Controller has got a very limited resources: no IRQ, no DMA, only a
single native chip-select and Tx/Rx FIFO with just 8 words depth
available. In order to provide a transparent initial boot code execution
the Boot SPI controller is also utilized by an vendor-specific IP-block,
which exposes an SPI flash direct mapping interface. Since both direct
mapping and SPI controller normal utilization are mutual exclusive only
one of these interfaces can be used to access an external SPI slave
device. That's why a dedicated mux is embedded into the System Boot
Controller. All of that is taken into account in the Baikal-T1-specific DW
APB SSI glue driver implemented by means of the DW SPI core module.
Co-developed-by: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Signed-off-by: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-22-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi/Kconfig')
| -rw-r--r-- | drivers/spi/Kconfig | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index db228121a40d..d2c976e55b8b 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -252,6 +252,34 @@ config SPI_DW_MMIO tristate "Memory-mapped io interface driver for DW SPI core" depends on HAS_IOMEM +config SPI_DW_BT1 + tristate "Baikal-T1 SPI driver for DW SPI core" + depends on MIPS_BAIKAL_T1 || COMPILE_TEST + help + Baikal-T1 SoC is equipped with three DW APB SSI-based MMIO SPI + controllers. Two of them are pretty much normal: with IRQ, DMA, + FIFOs of 64 words depth, 4x CSs, but the third one as being a + part of the Baikal-T1 System Boot Controller has got a very + limited resources: no IRQ, no DMA, only a single native + chip-select and Tx/Rx FIFO with just 8 words depth available. + The later one is normally connected to an external SPI-nor flash + of 128Mb (in general can be of bigger size). + +config SPI_DW_BT1_DIRMAP + bool "Directly mapped Baikal-T1 Boot SPI flash support" + depends on SPI_DW_BT1 + select MULTIPLEXER + select MUX_MMIO + help + Directly mapped SPI flash memory is an interface specific to the + Baikal-T1 System Boot Controller. It is a 16MB MMIO region, which + can be used to access a peripheral memory device just by + reading/writing data from/to it. Note that the system APB bus + will stall during each IO from/to the dirmap region until the + operation is finished. So try not to use it concurrently with + time-critical tasks (like the SPI memory operations implemented + in this driver). + endif config SPI_DLN2 |