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-rw-r--r--hw/ssi/xilinx_spips.c19
1 files changed, 10 insertions, 9 deletions
diff --git a/hw/ssi/xilinx_spips.c b/hw/ssi/xilinx_spips.c
index 559fa79e88..231aa5b6fb 100644
--- a/hw/ssi/xilinx_spips.c
+++ b/hw/ssi/xilinx_spips.c
@@ -208,14 +208,14 @@ static void xilinx_spips_reset(DeviceState *d)
xilinx_spips_update_cs_lines(s);
}
-/* N way (num) in place bit striper. Lay out row wise bits (LSB to MSB)
+/* N way (num) in place bit striper. Lay out row wise bits (MSB to LSB)
* column wise (from element 0 to N-1). num is the length of x, and dir
* reverses the direction of the transform. Best illustrated by example:
* Each digit in the below array is a single bit (num == 3):
*
- * {{ 76543210, } ----- stripe (dir == false) -----> {{ FCheb630, }
- * { hgfedcba, } { GDAfc741, }
- * { HGFEDCBA, }} <---- upstripe (dir == true) ----- { HEBgda52, }}
+ * {{ 76543210, } ----- stripe (dir == false) -----> {{ 741gdaFC, }
+ * { hgfedcba, } { 630fcHEB, }
+ * { HGFEDCBA, }} <---- upstripe (dir == true) ----- { 52hebGDA, }}
*/
static inline void stripe8(uint8_t *x, int num, bool dir)
@@ -223,15 +223,15 @@ static inline void stripe8(uint8_t *x, int num, bool dir)
uint8_t r[num];
memset(r, 0, sizeof(uint8_t) * num);
int idx[2] = {0, 0};
- int bit[2] = {0, 0};
+ int bit[2] = {0, 7};
int d = dir;
for (idx[0] = 0; idx[0] < num; ++idx[0]) {
- for (bit[0] = 0; bit[0] < 8; ++bit[0]) {
- r[idx[d]] |= x[idx[!d]] & 1 << bit[!d] ? 1 << bit[d] : 0;
+ for (bit[0] = 7; bit[0] >= 0; bit[0]--) {
+ r[idx[!d]] |= x[idx[d]] & 1 << bit[d] ? 1 << bit[!d] : 0;
idx[1] = (idx[1] + 1) % num;
if (!idx[1]) {
- bit[1]++;
+ bit[1]--;
}
}
}
@@ -266,8 +266,9 @@ static void xilinx_spips_flush_txfifo(XilinxSPIPS *s)
}
for (i = 0; i < num_effective_busses(s); ++i) {
+ int bus = num_effective_busses(s) - 1 - i;
DB_PRINT_L(debug_level, "tx = %02x\n", tx_rx[i]);
- tx_rx[i] = ssi_transfer(s->spi[i], (uint32_t)tx_rx[i]);
+ tx_rx[i] = ssi_transfer(s->spi[bus], (uint32_t)tx_rx[i]);
DB_PRINT_L(debug_level, "rx = %02x\n", tx_rx[i]);
}