hw/net/can/xlnx-versal-canfd: Fix byte ordering

The endianness of the CAN data was backwards in each group of 4 bytes.
For example, the following data:

00 11 22 33 44 55 66 77

was showing up like this:

33 22 11 00 77 66 55 44

Fix both the TX and RX code to put the data in the correct order.

Signed-off-by: Doug Brown <doug@schmorgal.com>
Reviewed-by: Francisco Iglesias <francisco.iglesias@amd.com>
Acked-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>
Message-id: 20240827034927.66659-6-doug@schmorgal.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --git a/hw/net/can/xlnx-versal-canfd.c b/hw/net/can/xlnx-versal-canfd.c
index 9fba5b9dfc55beeb9a71497172b83f6be4a8528b..bcfffee1cc2df56ee684f7cb1044d439adad1dd5 100644 (file)
--- a/hw/net/can/xlnx-versal-canfd.c
+++ b/hw/net/can/xlnx-versal-canfd.c
@@ -951,7 +951,7 @@ static void regs2frame(XlnxVersalCANFDState *s, qemu_can_frame *frame,
     }
 
     for (j = 0; j < frame->can_dlc; j++) {
-        val = 8 * i;
+        val = 8 * (3 - i);
 
         frame->data[j] = extract32(s->regs[reg_num + 2 + (j / 4)], val, 8);
         i++;
@@ -1093,19 +1093,19 @@ static void store_rx_sequential(XlnxVersalCANFDState *s,
             case 0:
                 rx_reg_num = i / 4;
 
-                data_reg_val = FIELD_DP32(0, RB_DW0_REGISTER, DATA_BYTES3,
+                data_reg_val = FIELD_DP32(0, RB_DW0_REGISTER, DATA_BYTES0,
                                           frame->data[i]);
                 break;
             case 1:
-                data_reg_val |= FIELD_DP32(0, RB_DW0_REGISTER, DATA_BYTES2,
+                data_reg_val |= FIELD_DP32(0, RB_DW0_REGISTER, DATA_BYTES1,
                                            frame->data[i]);
                 break;
             case 2:
-                data_reg_val |= FIELD_DP32(0, RB_DW0_REGISTER, DATA_BYTES1,
+                data_reg_val |= FIELD_DP32(0, RB_DW0_REGISTER, DATA_BYTES2,
                                            frame->data[i]);
                 break;
             case 3:
-                data_reg_val |= FIELD_DP32(0, RB_DW0_REGISTER, DATA_BYTES0,
+                data_reg_val |= FIELD_DP32(0, RB_DW0_REGISTER, DATA_BYTES3,
                                            frame->data[i]);
                 /*
                  * Last Bytes data which means we have all 4 bytes ready to