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-rw-r--r--src/soc/qualcomm/ipq806x/spi.c113
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);