Attention is currently required from: Nicholas Chin, Angel Pons.
qianfan has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/70529 )
Change subject: Add initial CH347T SPI programmer ......................................................................
Patch Set 3:
(5 comments)
File ch347t_spi.c:
https://review.coreboot.org/c/flashrom/+/70529/comment/73f4e4a5_38ceb749 PS2, Line 34: CH347_CMD_SPI_CONTROL,
Maybe make it more clear that this controls the CS lines?
Yes
File ch347t_spi.c:
https://review.coreboot.org/c/flashrom/+/70529/comment/49c7c3b1_ddb65f6b PS3, Line 30: #define CH347_MAX_DATA_READ 4096
This probably could be set to a higher value. […]
the 512 and 4096 is as same as WCH's dll so I copied those value there. And I try talk with WCH's FAE to detect the maximum value.
PS: I had test the CH347_MAX_DATA_READ, it also work even it is 1MiB.
https://review.coreboot.org/c/flashrom/+/70529/comment/910e1e3e_bb9d186b PS3, Line 41: enum spi_prescaler { : SPI_BAUDRATEPRESCALER_2 = 0x00, : SPI_BAUDRATEPRESCALER_4 = 0x08, : SPI_BAUDRATEPRESCALER_8 = 0x10, : SPI_BAUDRATEPRESCALER_16 = 0x18, : SPI_BAUDRATEPRESCALER_32 = 0x20, : SPI_BAUDRATEPRESCALER_64 = 0x28, : SPI_BAUDRATEPRESCALER_128 = 0x30, : SPI_BAUDRATEPRESCALER_256 = 0x38 : };
Alternatively the prescaler values could start from 1 and then the formula would be freq = 60 MHz / […]
CH347 is based on CH32VF3x, SPIx_CTLR1:BR[2:0] control the spi's clock, it has this defines:
000：FPCLK/2 001：FPCLK/4 010：FPCLK/8 011：FPCLK/16 100：FPCLK/32 101：FPCLK/64 110：FPCLK/128 111：FPCLK/256
So "enum spi_prescaler" is started from 1.
https://review.coreboot.org/c/flashrom/+/70529/comment/27df5846_614ff79e PS3, Line 84: enum spi_nss { : SPI_NSS_SOFT = 0x0200, : SPI_NSS_HARD = 0x0000 : };
I would rename these to be clearer what it does, maybe `enum spi_cs`, `SPI_CS_SOFTWARE`, and `SPI_CS […]
I don't know what this means, maybe it is used for spi device. On spi master, we control cs by command 0xC1.
https://review.coreboot.org/c/flashrom/+/70529/comment/46662d37_9b69bf3f PS3, Line 179: buf, n + 3,
This may go over the 512 byte max packet size of the write endpoint since n can be up to 512 due to […]
Let's use the default value as same as DLL. We can update this code when we got a clear reply that it can support a larger value.