From: Peter Delevoryas Date: Thu, 30 Jun 2022 07:21:13 +0000 (+0200) Subject: hw/i2c/aspeed: Fix DMA len write-enable bit handling X-Git-Tag: qemu-xen-4.18.0-rc5~640^2~6 X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=b582b7a191f23c3f862c3b3aef96d6136508c07f;p=qemu-xen.git hw/i2c/aspeed: Fix DMA len write-enable bit handling I noticed i2c rx transfers were getting shortened to "1" on Zephyr. It seems to be because the Zephyr i2c driver sets the RX DMA len with the RX field write-enable bit set (bit 31) to avoid a read-modify-write. [1] /* 0x1C : I2CM Master DMA Transfer Length Register */ I think we should be checking the write-enable bits on the incoming value, not checking the register array. I'm not sure we're even writing the write-enable bits to the register array, actually. [1] https://github.com/AspeedTech-BMC/zephyr/blob/db3dbcc9c52e67a47180890ac938ed380b33f91c/drivers/i2c/i2c_aspeed.c#L145-L148 Fixes: ba2cccd64e90f34 ("aspeed: i2c: Add new mode support") Signed-off-by: Peter Delevoryas Message-Id: <20220630045133.32251-3-me@pjd.dev> Reviewed-by: Cédric Le Goater Signed-off-by: Cédric Le Goater --- diff --git a/hw/i2c/aspeed_i2c.c b/hw/i2c/aspeed_i2c.c index 6429ab1874..4e32b147ec 100644 --- a/hw/i2c/aspeed_i2c.c +++ b/hw/i2c/aspeed_i2c.c @@ -644,18 +644,18 @@ static void aspeed_i2c_bus_new_write(AspeedI2CBus *bus, hwaddr offset, RX_BUF_LEN) + 1; break; case A_I2CM_DMA_LEN: - w1t = ARRAY_FIELD_EX32(bus->regs, I2CM_DMA_LEN, RX_BUF_LEN_W1T) || - ARRAY_FIELD_EX32(bus->regs, I2CM_DMA_LEN, TX_BUF_LEN_W1T); + w1t = FIELD_EX32(value, I2CM_DMA_LEN, RX_BUF_LEN_W1T) || + FIELD_EX32(value, I2CM_DMA_LEN, TX_BUF_LEN_W1T); /* If none of the w1t bits are set, just write to the reg as normal. */ if (!w1t) { bus->regs[R_I2CM_DMA_LEN] = value; break; } - if (ARRAY_FIELD_EX32(bus->regs, I2CM_DMA_LEN, RX_BUF_LEN_W1T)) { + if (FIELD_EX32(value, I2CM_DMA_LEN, RX_BUF_LEN_W1T)) { ARRAY_FIELD_DP32(bus->regs, I2CM_DMA_LEN, RX_BUF_LEN, FIELD_EX32(value, I2CM_DMA_LEN, RX_BUF_LEN)); } - if (ARRAY_FIELD_EX32(bus->regs, I2CM_DMA_LEN, TX_BUF_LEN_W1T)) { + if (FIELD_EX32(value, I2CM_DMA_LEN, TX_BUF_LEN_W1T)) { ARRAY_FIELD_DP32(bus->regs, I2CM_DMA_LEN, TX_BUF_LEN, FIELD_EX32(value, I2CM_DMA_LEN, TX_BUF_LEN)); }