From 6ed924823c87999191776a2bd9a56efd3d83a387 Mon Sep 17 00:00:00 2001 From: Bin Meng Date: Fri, 29 Jan 2021 21:23:22 +0800 Subject: hw/ssi: imx_spi: Correct the burst length > 32 bit transfer logic For the ECSPIx_CONREG register BURST_LENGTH field, the manual says: 0x020 A SPI burst contains the 1 LSB in first word and all 32 bits in second word. 0x021 A SPI burst contains the 2 LSB in first word and all 32 bits in second word. Current logic uses either s->burst_length or 32, whichever smaller, to determine how many bits it should read from the tx fifo each time. For example, for a 48 bit burst length, current logic transfers the first 32 bit from the first word in the tx fifo, followed by a 16 bit from the second word in the tx fifo, which is wrong. The correct logic should be: transfer the first 16 bit from the first word in the tx fifo, followed by a 32 bit from the second word in the tx fifo. With this change, SPI flash can be successfully probed by U-Boot on imx6 sabrelite board. => sf probe SF: Detected sst25vf016b with page size 256 Bytes, erase size 4 KiB, total 2 MiB Fixes: c906a3a01582 ("i.MX: Add the Freescale SPI Controller") Signed-off-by: Bin Meng Reviewed-by: Philippe Mathieu-Daudé Message-id: 20210129132323.30946-10-bmeng.cn@gmail.com Signed-off-by: Peter Maydell --- hw/ssi/imx_spi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/hw/ssi/imx_spi.c b/hw/ssi/imx_spi.c index 41fe199c9f..a34194c1b0 100644 --- a/hw/ssi/imx_spi.c +++ b/hw/ssi/imx_spi.c @@ -185,7 +185,7 @@ static void imx_spi_flush_txfifo(IMXSPIState *s) DPRINTF("data tx:0x%08x\n", tx); - tx_burst = MIN(s->burst_length, 32); + tx_burst = (s->burst_length % 32) ? : 32; rx = 0; -- cgit v1.2.3-55-g7522