diff options
Diffstat (limited to 'hw/ssi')
| -rw-r--r-- | hw/ssi/xilinx_spips.c | 84 |
1 files changed, 63 insertions, 21 deletions
diff --git a/hw/ssi/xilinx_spips.c b/hw/ssi/xilinx_spips.c index 3e9e76c165..7222e152e6 100644 --- a/hw/ssi/xilinx_spips.c +++ b/hw/ssi/xilinx_spips.c @@ -273,35 +273,77 @@ 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) + * 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, }} + */ + +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 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; + idx[1] = (idx[1] + 1) % num; + if (!idx[1]) { + bit[1]++; + } + } + } + memcpy(x, r, sizeof(uint8_t) * num); +} + static void xilinx_spips_flush_txfifo(XilinxSPIPS *s) { for (;;) { int i; - uint8_t rx; uint8_t tx = 0; + uint8_t tx_rx[num_effective_busses(s)]; - for (i = 0; i < num_effective_busses(s); ++i) { - if (!i || s->snoop_state == SNOOP_STRIPING) { - if (fifo8_is_empty(&s->tx_fifo)) { - if (!(s->regs[R_LQSPI_CFG] & LQSPI_CFG_LQ_MODE)) { - s->regs[R_INTR_STATUS] |= IXR_TX_FIFO_UNDERFLOW; - } - xilinx_spips_update_ixr(s); - return; - } else { - tx = fifo8_pop(&s->tx_fifo); - } + if (fifo8_is_empty(&s->tx_fifo)) { + if (!(s->regs[R_LQSPI_CFG] & LQSPI_CFG_LQ_MODE)) { + s->regs[R_INTR_STATUS] |= IXR_TX_FIFO_UNDERFLOW; } - rx = ssi_transfer(s->spi[i], (uint32_t)tx); - DB_PRINT("tx = %02x rx = %02x\n", tx, rx); - if (!i || s->snoop_state == SNOOP_STRIPING) { - if (fifo8_is_full(&s->rx_fifo)) { - s->regs[R_INTR_STATUS] |= IXR_RX_FIFO_OVERFLOW; - DB_PRINT("rx FIFO overflow"); - } else { - fifo8_push(&s->rx_fifo, (uint8_t)rx); - } + xilinx_spips_update_ixr(s); + return; + } else if (s->snoop_state == SNOOP_STRIPING) { + for (i = 0; i < num_effective_busses(s); ++i) { + tx_rx[i] = fifo8_pop(&s->tx_fifo); } + stripe8(tx_rx, num_effective_busses(s), false); + } else { + tx = fifo8_pop(&s->tx_fifo); + for (i = 0; i < num_effective_busses(s); ++i) { + tx_rx[i] = tx; + } + } + + for (i = 0; i < num_effective_busses(s); ++i) { + DB_PRINT("tx = %02x\n", tx_rx[i]); + tx_rx[i] = ssi_transfer(s->spi[i], (uint32_t)tx_rx[i]); + DB_PRINT("rx = %02x\n", tx_rx[i]); + } + + if (fifo8_is_full(&s->rx_fifo)) { + s->regs[R_INTR_STATUS] |= IXR_RX_FIFO_OVERFLOW; + DB_PRINT("rx FIFO overflow"); + } else if (s->snoop_state == SNOOP_STRIPING) { + stripe8(tx_rx, num_effective_busses(s), true); + for (i = 0; i < num_effective_busses(s); ++i) { + fifo8_push(&s->rx_fifo, (uint8_t)tx_rx[i]); + } + } else { + fifo8_push(&s->rx_fifo, (uint8_t)tx_rx[0]); } switch (s->snoop_state) { |