[PATCH v2 04/11] spi: cadence-qspi: store device data pointer in private struct

Théo Lebrun
2024-04-05T15:02:19Z

Avoid of_device_get_match_data() call on each IRQ and each read
operation. Store pointer in `struct cqspi_st` device instance.

End-to-end performance measurements improve with this patch. On a given
octal flash, reading 235M over UBIFS is ~3.4% faster. During that read,
the average cqspi_exec_mem_op() call goes from 85.4µs to 80.7µs
according to ftrace. The worst case goes from 622.4µs to 615.2µs.

Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
---
drivers/spi/spi-cadence-quadspi.c | 15 ++++++---------
1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-cadence-quadspi.c
index 350b3dab3a05..abc1c35929cc 100644
--- a/drivers/spi/spi-cadence-quadspi.c
+++ b/drivers/spi/spi-cadence-quadspi.c
@@ -102,6 +102,8 @@ struct cqspi_st {
bool apb_ahb_hazard;

bool is_jh7110; /* Flag for StarFive JH7110 SoC */
+
+ const struct cqspi_driver_platdata *ddata;
};

struct cqspi_driver_platdata {
@@ -334,11 +336,8 @@ static u32 cqspi_get_versal_dma_status(struct cqspi_st *cqspi)
static irqreturn_t cqspi_irq_handler(int this_irq, void *dev)
{
struct cqspi_st *cqspi = dev;
+ const struct cqspi_driver_platdata *ddata = cqspi->ddata;
unsigned int irq_status;
- struct device *device = &cqspi->pdev->dev;
- const struct cqspi_driver_platdata *ddata;
-
- ddata = of_device_get_match_data(device);

/* Read interrupt status */
irq_status = readl(cqspi->iobase + CQSPI_REG_IRQSTATUS);
@@ -1358,16 +1357,13 @@ static ssize_t cqspi_read(struct cqspi_flash_pdata *f_pdata,
const struct spi_mem_op *op)
{
struct cqspi_st *cqspi = f_pdata->cqspi;
- struct device *dev = &cqspi->pdev->dev;
- const struct cqspi_driver_platdata *ddata;
+ const struct cqspi_driver_platdata *ddata = cqspi->ddata;
loff_t from = op->addr.val;
size_t len = op->data.nbytes;
u_char *buf = op->data.buf.in;
u64 dma_align = (u64)(uintptr_t)buf;
int ret;

- ddata = of_device_get_match_data(dev);
-
ret = cqspi_read_setup(f_pdata, op);
if (ret)
return ret;
@@ -1822,7 +1818,8 @@ static int cqspi_probe(struct platform_device *pdev)
/* write completion is supported by default */
cqspi->wr_completion = true;

- ddata = of_device_get_match_data(dev);
+ ddata = of_device_get_match_data(dev);
+ cqspi->ddata = ddata;
if (ddata) {
if (ddata->quirks & CQSPI_NEEDS_WR_DELAY)
cqspi->wr_delay = 50 * DIV_ROUND_UP(NSEC_PER_SEC,

--
2.44.0