The Pensando Elba SoC has the Cadence QSPI controller integrated.
The quirk CQSPI_NEEDS_APB_AHB_HAZARD_WAR is added and if enabled
a dummy readback from the controller is performed to ensure
synchronization.
Signed-off-by: Brad Larson <brad@xxxxxxxxxxx>
---
drivers/spi/spi-cadence-quadspi.c | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)
diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-cadence-quadspi.c
index 101cc71bffa7..af36514250d2 100644
--- a/drivers/spi/spi-cadence-quadspi.c
+++ b/drivers/spi/spi-cadence-quadspi.c
@@ -35,6 +35,7 @@
/* Quirks */
#define CQSPI_NEEDS_WR_DELAY BIT(0)
#define CQSPI_DISABLE_DAC_MODE BIT(1)
+#define CQSPI_NEEDS_APB_AHB_HAZARD_WAR BIT(2)
/* Capabilities */
#define CQSPI_SUPPORTS_OCTAL BIT(0)
@@ -74,6 +75,7 @@ struct cqspi_st {
int current_cs;
unsigned long master_ref_clk_hz;
bool is_decoded_cs;
+ bool apb_ahb_hazard;
u32 fifo_depth;
u32 fifo_width;
u32 num_chipselect;
@@ -862,6 +864,13 @@ static int cqspi_indirect_write_execute(struct cqspi_flash_pdata *f_pdata,
if (cqspi->wr_delay)
ndelay(cqspi->wr_delay);
+ /*
+ * If a hazard exists between the APB and AHB interfaces, perform a
+ * dummy readback from the controller to ensure synchronization.
+ */
+ if (cqspi->apb_ahb_hazard)
+ (void)readl(reg_base + CQSPI_REG_INDIRECTWR);
+
while (remaining > 0) {
size_t write_words, mod_bytes;
@@ -1548,6 +1557,8 @@ static int cqspi_probe(struct platform_device *pdev)
master->mode_bits |= SPI_RX_OCTAL | SPI_TX_OCTAL;
if (!(ddata->quirks & CQSPI_DISABLE_DAC_MODE))
cqspi->use_direct_mode = true;
+ if (ddata->quirks & CQSPI_NEEDS_APB_AHB_HAZARD_WAR)
+ cqspi->apb_ahb_hazard = true;
}
ret = devm_request_irq(dev, irq, cqspi_irq_handler, 0,
@@ -1656,6 +1667,10 @@ static const struct cqspi_driver_platdata intel_lgm_qspi = {
.quirks = CQSPI_DISABLE_DAC_MODE,
};
+static const struct cqspi_driver_platdata pen_cdns_qspi = {
+ .quirks = CQSPI_NEEDS_APB_AHB_HAZARD_WAR | CQSPI_DISABLE_DAC_MODE,
+};
+
static const struct of_device_id cqspi_dt_ids[] = {
{
.compatible = "cdns,qspi-nor",
@@ -1673,6 +1688,10 @@ static const struct of_device_id cqspi_dt_ids[] = {
.compatible = "intel,lgm-qspi",
.data = &intel_lgm_qspi,
},
+ {
+ .compatible = "pensando,elba-qspi",
+ .data = &pen_cdns_qspi,
+ },
{ /* end of table */ }
};
--
2.17.1
