/openbmc/linux/Documentation/devicetree/bindings/spi/ |
H A D | fsl-spi.txt | 69b921ac Wed Mar 06 04:32:05 CST 2019 Rasmus Villemoes <rasmus.villemoes@prevas.dk> spi: spi-fsl-spi: support use of the SPISEL_BOOT signal on MPC8309
The MPC8309 has a dedicated signal, SPISEL_BOOT, usually used as chip select for the flash device from which the bootloader is loaded. It is not an ordinary gpio, but is simply controlled via the SPI_CS register in the system configuration.
To allow accessing such a spi slave, we need to teach fsl_spi_cs_control() how to control the SPISEL_BOOT signal. To distinguish the gpio-controlled slaves, continue to have those use chip_select values of 0..ngpios-1, and use chip_select == ngpios for the boot flash.
I'm not too happy with all the ifdeffery, but it seems to be necessary for guarding the sysdev/fsl_soc.h and use of get_immrbase() (spi-fsl-lib.c already contains similar ifdeffery).
Googling suggests that the MPC8306 is similar, with the SPI_CS register at the same offset.
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk> Signed-off-by: Mark Brown <broonie@kernel.org> 69b921ac Wed Mar 06 04:32:05 CST 2019 Rasmus Villemoes <rasmus.villemoes@prevas.dk> spi: spi-fsl-spi: support use of the SPISEL_BOOT signal on MPC8309 The MPC8309 has a dedicated signal, SPISEL_BOOT, usually used as chip select for the flash device from which the bootloader is loaded. It is not an ordinary gpio, but is simply controlled via the SPI_CS register in the system configuration. To allow accessing such a spi slave, we need to teach fsl_spi_cs_control() how to control the SPISEL_BOOT signal. To distinguish the gpio-controlled slaves, continue to have those use chip_select values of 0..ngpios-1, and use chip_select == ngpios for the boot flash. I'm not too happy with all the ifdeffery, but it seems to be necessary for guarding the sysdev/fsl_soc.h and use of get_immrbase() (spi-fsl-lib.c already contains similar ifdeffery). Googling suggests that the MPC8306 is similar, with the SPI_CS register at the same offset. Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk> Signed-off-by: Mark Brown <broonie@kernel.org>
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/openbmc/linux/drivers/spi/ |
H A D | spi-fsl-lib.h | 69b921ac Wed Mar 06 04:32:05 CST 2019 Rasmus Villemoes <rasmus.villemoes@prevas.dk> spi: spi-fsl-spi: support use of the SPISEL_BOOT signal on MPC8309
The MPC8309 has a dedicated signal, SPISEL_BOOT, usually used as chip select for the flash device from which the bootloader is loaded. It is not an ordinary gpio, but is simply controlled via the SPI_CS register in the system configuration.
To allow accessing such a spi slave, we need to teach fsl_spi_cs_control() how to control the SPISEL_BOOT signal. To distinguish the gpio-controlled slaves, continue to have those use chip_select values of 0..ngpios-1, and use chip_select == ngpios for the boot flash.
I'm not too happy with all the ifdeffery, but it seems to be necessary for guarding the sysdev/fsl_soc.h and use of get_immrbase() (spi-fsl-lib.c already contains similar ifdeffery).
Googling suggests that the MPC8306 is similar, with the SPI_CS register at the same offset.
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk> Signed-off-by: Mark Brown <broonie@kernel.org> 69b921ac Wed Mar 06 04:32:05 CST 2019 Rasmus Villemoes <rasmus.villemoes@prevas.dk> spi: spi-fsl-spi: support use of the SPISEL_BOOT signal on MPC8309 The MPC8309 has a dedicated signal, SPISEL_BOOT, usually used as chip select for the flash device from which the bootloader is loaded. It is not an ordinary gpio, but is simply controlled via the SPI_CS register in the system configuration. To allow accessing such a spi slave, we need to teach fsl_spi_cs_control() how to control the SPISEL_BOOT signal. To distinguish the gpio-controlled slaves, continue to have those use chip_select values of 0..ngpios-1, and use chip_select == ngpios for the boot flash. I'm not too happy with all the ifdeffery, but it seems to be necessary for guarding the sysdev/fsl_soc.h and use of get_immrbase() (spi-fsl-lib.c already contains similar ifdeffery). Googling suggests that the MPC8306 is similar, with the SPI_CS register at the same offset. Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk> Signed-off-by: Mark Brown <broonie@kernel.org>
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H A D | spi-fsl-spi.c | 69b921ac Wed Mar 06 04:32:05 CST 2019 Rasmus Villemoes <rasmus.villemoes@prevas.dk> spi: spi-fsl-spi: support use of the SPISEL_BOOT signal on MPC8309
The MPC8309 has a dedicated signal, SPISEL_BOOT, usually used as chip select for the flash device from which the bootloader is loaded. It is not an ordinary gpio, but is simply controlled via the SPI_CS register in the system configuration.
To allow accessing such a spi slave, we need to teach fsl_spi_cs_control() how to control the SPISEL_BOOT signal. To distinguish the gpio-controlled slaves, continue to have those use chip_select values of 0..ngpios-1, and use chip_select == ngpios for the boot flash.
I'm not too happy with all the ifdeffery, but it seems to be necessary for guarding the sysdev/fsl_soc.h and use of get_immrbase() (spi-fsl-lib.c already contains similar ifdeffery).
Googling suggests that the MPC8306 is similar, with the SPI_CS register at the same offset.
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk> Signed-off-by: Mark Brown <broonie@kernel.org> 69b921ac Wed Mar 06 04:32:05 CST 2019 Rasmus Villemoes <rasmus.villemoes@prevas.dk> spi: spi-fsl-spi: support use of the SPISEL_BOOT signal on MPC8309 The MPC8309 has a dedicated signal, SPISEL_BOOT, usually used as chip select for the flash device from which the bootloader is loaded. It is not an ordinary gpio, but is simply controlled via the SPI_CS register in the system configuration. To allow accessing such a spi slave, we need to teach fsl_spi_cs_control() how to control the SPISEL_BOOT signal. To distinguish the gpio-controlled slaves, continue to have those use chip_select values of 0..ngpios-1, and use chip_select == ngpios for the boot flash. I'm not too happy with all the ifdeffery, but it seems to be necessary for guarding the sysdev/fsl_soc.h and use of get_immrbase() (spi-fsl-lib.c already contains similar ifdeffery). Googling suggests that the MPC8306 is similar, with the SPI_CS register at the same offset. Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk> Signed-off-by: Mark Brown <broonie@kernel.org>
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