Commit c3725b85 authored by Francisco Iglesias's avatar Francisco Iglesias Committed by Peter Maydell
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xilinx_spips: Update striping to be big-endian bit order 



Update striping functionality to be big-endian bit order (as according to
the Zynq-7000 Technical Reference Manual). Output thereafter the even bits
into the flash memory connected to the lower QSPI bus and the odd bits into
the flash memory connected to the upper QSPI bus.

Signed-off-by: default avatarFrancisco Iglesias <frasse.iglesias@gmail.com>
Acked-by: default avatarAlistair Francis <alistair.francis@xilinx.com>
Reviewed-by: default avatarEdgar E. Iglesias <edgar.iglesias@xilinx.com>
Tested-by: default avatarEdgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 20171126231634.9531-7-frasse.iglesias@gmail.com
Signed-off-by: default avatarPeter Maydell <peter.maydell@linaro.org>
parent 5394dbcc

hw/ssi/xilinx_spips.c

+10 −9
Original line number Diff line number Diff line
@@ -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]);

        }