[PATCH 4/4] i3c: mipi-i3c-hci: Round IBI data chunk size to HW supported value

[Jarkko Nikula]

The dma.c: hci_dma_init() sets the CHUNK_SIZE field in the IBI_SETUP
register incorrectly if the calculated ibi_chunk_sz is not exactly
2^(n+2) bytes, where n is 0..6.

Fix this by rounding the chunk size up to nearest 2^(n+2) bytes.

Signed-off-by: Jarkko Nikula <jarkko.nikula at linux.intel.com>
---
 drivers/i3c/master/mipi-i3c-hci/dma.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/i3c/master/mipi-i3c-hci/dma.c b/drivers/i3c/master/mipi-i3c-hci/dma.c
index 9bdfe40bc1e1..a918e96b21fd 100644
--- a/drivers/i3c/master/mipi-i3c-hci/dma.c
+++ b/drivers/i3c/master/mipi-i3c-hci/dma.c
@@ -279,6 +279,13 @@ static int hci_dma_init(struct i3c_hci *hci)
 
 		rh->ibi_chunk_sz = dma_get_cache_alignment();
 		rh->ibi_chunk_sz *= IBI_CHUNK_CACHELINES;
+		/*
+		 * Round IBI data chunk size to number of bytes supported by
+		 * the HW. Chunk size can be 2^n number of DWORDs which is the
+		 * same as 2^(n+2) bytes, where n is 0..6.
+		 */
+		rh->ibi_chunk_sz = umax(4, rh->ibi_chunk_sz);
+		rh->ibi_chunk_sz = roundup_pow_of_two(rh->ibi_chunk_sz);
 		if (rh->ibi_chunk_sz > 256) {
 			ret = -EINVAL;
 			goto err_out;
-- 
2.43.0