GSC SPI HW errors on quad access overlapping 1K border.
Align 64bit read and write to avoid readq/writeq over 1K border.
Signed-off-by: Alexander Usyskin <alexander.usyskin@xxxxxxxxx>
---
drivers/spi/spi-intel-dg.c | 35 +++++++++++++++++++++++++++++++++++
1 file changed, 35 insertions(+)
diff --git a/drivers/spi/spi-intel-dg.c b/drivers/spi/spi-intel-dg.c
index dfb457c43a5d..c76b0a70f8d8 100644
--- a/drivers/spi/spi-intel-dg.c
+++ b/drivers/spi/spi-intel-dg.c
@@ -231,6 +231,24 @@ static ssize_t spi_write(struct intel_dg_spi *spi, u8 region,
len_s -= to_shift;
}
+ if (!IS_ALIGNED(to, sizeof(u64)) &&
+ ((to ^ (to + len_s)) & GENMASK(31, 10))) {
+ /*
+ * Workaround reads/writes across 1k-aligned addresses
+ * (start u32 before 1k, end u32 after)
+ * as this fails on hardware.
+ */
+ u32 data;
+
+ memcpy(&data, &buf[0], sizeof(u32));
+ spi_write32(spi, to, data);
+ if (spi_error(spi))
+ return -EIO;
+ buf += sizeof(u32);
+ to += sizeof(u32);
+ len_s -= sizeof(u32);
+ }
+
len8 = ALIGN_DOWN(len_s, sizeof(u64));
for (i = 0; i < len8; i += sizeof(u64)) {
u64 data;
@@ -289,6 +307,23 @@ static ssize_t spi_read(struct intel_dg_spi *spi, u8 region,
from += from_shift;
}
+ if (!IS_ALIGNED(from, sizeof(u64)) &&
+ ((from ^ (from + len_s)) & GENMASK(31, 10))) {
+ /*
+ * Workaround reads/writes across 1k-aligned addresses
+ * (start u32 before 1k, end u32 after)
+ * as this fails on hardware.
+ */
+ u32 data = spi_read32(spi, from);
+
+ if (spi_error(spi))
+ return -EIO;
+ memcpy(&buf[0], &data, sizeof(data));
+ len_s -= sizeof(u32);
+ buf += sizeof(u32);
+ from += sizeof(u32);
+ }
+
len8 = ALIGN_DOWN(len_s, sizeof(u64));
for (i = 0; i < len8; i += sizeof(u64)) {
u64 data = spi_read64(spi, from + i);
--
2.34.1
