diff options
| -rw-r--r-- | src/soc/qualcomm/ipq806x/spi.c | 113 |
1 files changed, 75 insertions, 38 deletions
diff --git a/src/soc/qualcomm/ipq806x/spi.c b/src/soc/qualcomm/ipq806x/spi.c index f1a180ba88..2c16cb6388 100644 --- a/src/soc/qualcomm/ipq806x/spi.c +++ b/src/soc/qualcomm/ipq806x/spi.c @@ -34,6 +34,11 @@ #define GSBI_IDX_TO_GSBI(idx) (idx + 5) + +/* MX_INPUT_COUNT and MX_OUTPUT_COUNT are 16-bits. Zero has a special meaning + * (count function disabled) and does not hold significance in the count. */ +#define MAX_PACKET_COUNT ((64 * KiB) - 1) + /* * TLMM Configuration for SPI NOR * gsbi_pin_conf[bus_num][GPIO_NUM, FUNC_SEL, I/O, @@ -644,12 +649,66 @@ void spi_release_bus(struct spi_slave *slave) ds->initialized = 0; } +static int spi_xfer_tx_packet(struct ipq_spi_slave *ds, + const uint8_t *dout, unsigned out_bytes) +{ + int ret; + + writel_i(out_bytes, ds->regs->qup_mx_output_count); + + ret = config_spi_state(ds, SPI_RUN_STATE); + if (ret) + return ret; + + while (out_bytes) { + if (readl_i(ds->regs->qup_operational) & QUP_OUTPUT_FIFO_FULL) + continue; + + writel_i(*dout++, ds->regs->qup_output_fifo); + out_bytes--; + + /* Wait for output FIFO to drain. */ + if (!out_bytes) + while (readl_i(ds->regs->qup_operational) & + QUP_OUTPUT_FIFO_NOT_EMPTY) + ; + } + + return config_spi_state(ds, SPI_RESET_STATE); +} + +static int spi_xfer_rx_packet(struct ipq_spi_slave *ds, + uint8_t *din, unsigned in_bytes) +{ + int ret; + + writel_i(in_bytes, ds->regs->qup_mx_input_count); + writel_i(in_bytes, ds->regs->qup_mx_output_count); + + ret = config_spi_state(ds, SPI_RUN_STATE); + if (ret) + return ret; + + /* Seed clocking */ + writel_i(0xff, ds->regs->qup_output_fifo); + while (in_bytes) { + if (!(readl_i(ds->regs->qup_operational) & + QUP_INPUT_FIFO_NOT_EMPTY)) + continue; + /* Keep it clocking */ + writel_i(0xff, ds->regs->qup_output_fifo); + + *din++ = readl_i(ds->regs->qup_input_fifo) & 0xff; + in_bytes--; + } + + return config_spi_state(ds, SPI_RESET_STATE); +} + int spi_xfer(struct spi_slave *slave, const void *dout, unsigned out_bytes, void *din, unsigned in_bytes) { int ret; - uint8_t* dbuf; - const uint8_t* dobuf; struct ipq_spi_slave *ds = to_ipq_spi(slave); /* Assert the chip select */ @@ -669,29 +728,17 @@ int spi_xfer(struct spi_slave *slave, const void *dout, clrsetbits_le32_i(ds->regs->qup_config, SPI_QUP_CONF_OUTPUT_MSK, SPI_QUP_CONF_OUTPUT_ENA); - writel_i(out_bytes, ds->regs->qup_mx_output_count); - - ret = config_spi_state(ds, SPI_RUN_STATE); - if (ret) - goto out; - - dobuf = dout; /* Alias to make it possible to use pointer autoinc. */ - while (out_bytes) { - if (readl_i(ds->regs->qup_operational) & QUP_OUTPUT_FIFO_FULL) - continue; + unsigned todo = MIN(out_bytes, MAX_PACKET_COUNT); - writel_i(*dobuf++, ds->regs->qup_output_fifo); - out_bytes--; + ret = spi_xfer_tx_packet(ds, dout, todo); + if (ret) + break; - /* Wait for output FIFO to drain. */ - if (!out_bytes) - while (readl_i(ds->regs->qup_operational) & - QUP_OUTPUT_FIFO_NOT_EMPTY) - ; + out_bytes -= todo; + dout += todo; } - ret = config_spi_state(ds, SPI_RESET_STATE); if (ret) goto out; @@ -703,28 +750,18 @@ spi_receive: clrsetbits_le32_i(ds->regs->qup_config, SPI_QUP_CONF_INPUT_MSK, SPI_QUP_CONF_INPUT_ENA); - writel_i(in_bytes, ds->regs->qup_mx_input_count); - writel_i(in_bytes, ds->regs->qup_mx_output_count); - - ret = config_spi_state(ds, SPI_RUN_STATE); - if (ret) - goto out; - - /* Seed clocking */ - writel_i(0xff, ds->regs->qup_output_fifo); - dbuf = din; /* Alias for pointer autoincrement again. */ while (in_bytes) { - if (!(readl_i(ds->regs->qup_operational) & - QUP_INPUT_FIFO_NOT_EMPTY)) - continue; - /* Keep it clocking */ - writel_i(0xff, ds->regs->qup_output_fifo); + unsigned todo = MIN(in_bytes, MAX_PACKET_COUNT); - *dbuf++ = readl_i(ds->regs->qup_input_fifo) & 0xff; - in_bytes--; + ret = spi_xfer_rx_packet(ds, din, todo); + if (ret) + break; + + in_bytes -= todo; + din += todo; } - out: +out: /* Deassert CS */ CS_change(ds->slave.bus, ds->slave.cs, CS_DEASSERT); |