From: Marek Behún Date: Wed, 8 Apr 2020 10:02:03 +0000 (+0200) Subject: arm: mvebu: turris_mox: Fix early SPI communication X-Git-Tag: v2020.10~289^2~10 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=b80ca8176dc0e78d3fb22b2389c847a5d96ee583;p=platform%2Fkernel%2Fu-boot.git arm: mvebu: turris_mox: Fix early SPI communication The SPI clock signal changes value when the SPI configuration register is configured. This can sometimes lead to the device misinterpreting the enablement of the SPI controller as actual clock tick. This can be solved by first setting the SPI CS1 pin from GPIO to SPI mode, and only after that writing the SPI configuration register. Signed-off-by: Marek Behún Reviewed-by: Stefan Roese --- diff --git a/board/CZ.NIC/turris_mox/turris_mox.c b/board/CZ.NIC/turris_mox/turris_mox.c index 377191b..0b13d1d 100644 --- a/board/CZ.NIC/turris_mox/turris_mox.c +++ b/board/CZ.NIC/turris_mox/turris_mox.c @@ -67,9 +67,11 @@ int board_fix_fdt(void *blob) * to read SPI by reading/writing SPI registers directly */ - writel(0x563fa, ARMADA_37XX_NB_GPIO_SEL); writel(0x10df, ARMADA_37XX_SPI_CFG); - writel(0x2005b, ARMADA_37XX_SPI_CTRL); + /* put pin from GPIO to SPI mode */ + clrbits_le32(ARMADA_37XX_NB_GPIO_SEL, BIT(12)); + /* enable SPI CS1 */ + setbits_le32(ARMADA_37XX_SPI_CTRL, BIT(17)); while (!(readl(ARMADA_37XX_SPI_CTRL) & 0x2)) udelay(1); @@ -89,7 +91,8 @@ int board_fix_fdt(void *blob) size = i; - writel(0x5b, ARMADA_37XX_SPI_CTRL); + /* disable SPI CS1 */ + clrbits_le32(ARMADA_37XX_SPI_CTRL, BIT(17)); if (size > 1 && (topology[1] == MOX_MODULE_PCI || topology[1] == MOX_MODULE_USB3 ||