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.usys...@intel.com>
---
 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 9e8be7713f1a..d626e9526631 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

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