Merge tag 'spi-fix-v6.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi fixes from Mark Brown:
"A bunch of fixes for the Qualcomm QSPI driver, fixing multiple issues
with the newly added DMA mode - it had a number of issues exposed when
tested in a wider range of use cases, both race condition style issues
and issues with different inputs to those that had been used in test"
* tag 'spi-fix-v6.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
spi: spi-qcom-qspi: Add mem_ops to avoid PIO for badly sized reads
spi: spi-qcom-qspi: Fallback to PIO for xfers that aren't multiples of 4 bytes
spi: spi-qcom-qspi: Add DMA_CHAIN_DONE to ALL_IRQS
spi: spi-qcom-qspi: Call dma_wmb() after setting up descriptors
spi: spi-qcom-qspi: Use GFP_ATOMIC flag while allocating for descriptor
spi: spi-qcom-qspi: Ignore disabled interrupts' status in isr
diff --git a/drivers/spi/spi-qcom-qspi.c b/drivers/spi/spi-qcom-qspi.c
index a8a683d..1954c39 100644
--- a/drivers/spi/spi-qcom-qspi.c
+++ b/drivers/spi/spi-qcom-qspi.c
@@ -69,7 +69,7 @@
WR_FIFO_OVERRUN)
#define QSPI_ALL_IRQS (QSPI_ERR_IRQS | RESP_FIFO_RDY | \
WR_FIFO_EMPTY | WR_FIFO_FULL | \
- TRANSACTION_DONE)
+ TRANSACTION_DONE | DMA_CHAIN_DONE)
#define PIO_XFER_CTRL 0x0014
#define REQUEST_COUNT_MSK 0xffff
@@ -308,9 +308,11 @@
dma_addr_t dma_cmd_desc;
/* allocate for dma cmd descriptor */
- virt_cmd_desc = dma_pool_alloc(ctrl->dma_cmd_pool, GFP_KERNEL | __GFP_ZERO, &dma_cmd_desc);
- if (!virt_cmd_desc)
- return -ENOMEM;
+ virt_cmd_desc = dma_pool_alloc(ctrl->dma_cmd_pool, GFP_ATOMIC | __GFP_ZERO, &dma_cmd_desc);
+ if (!virt_cmd_desc) {
+ dev_warn_once(ctrl->dev, "Couldn't find memory for descriptor\n");
+ return -EAGAIN;
+ }
ctrl->virt_cmd_desc[ctrl->n_cmd_desc] = virt_cmd_desc;
ctrl->dma_cmd_desc[ctrl->n_cmd_desc] = dma_cmd_desc;
@@ -355,10 +357,22 @@
for (i = 0; i < sgt->nents; i++) {
dma_ptr_sg = sg_dma_address(sgt->sgl + i);
+ dma_len_sg = sg_dma_len(sgt->sgl + i);
if (!IS_ALIGNED(dma_ptr_sg, QSPI_ALIGN_REQ)) {
dev_warn_once(ctrl->dev, "dma_address not aligned to %d\n", QSPI_ALIGN_REQ);
return -EAGAIN;
}
+ /*
+ * When reading with DMA the controller writes to memory 1 word
+ * at a time. If the length isn't a multiple of 4 bytes then
+ * the controller can clobber the things later in memory.
+ * Fallback to PIO to be safe.
+ */
+ if (ctrl->xfer.dir == QSPI_READ && (dma_len_sg & 0x03)) {
+ dev_warn_once(ctrl->dev, "fallback to PIO for read of size %#010x\n",
+ dma_len_sg);
+ return -EAGAIN;
+ }
}
for (i = 0; i < sgt->nents; i++) {
@@ -441,8 +455,10 @@
ret = qcom_qspi_setup_dma_desc(ctrl, xfer);
if (ret != -EAGAIN) {
- if (!ret)
+ if (!ret) {
+ dma_wmb();
qcom_qspi_dma_xfer(ctrl);
+ }
goto exit;
}
dev_warn_once(ctrl->dev, "DMA failure, falling back to PIO\n");
@@ -603,6 +619,9 @@
int_status = readl(ctrl->base + MSTR_INT_STATUS);
writel(int_status, ctrl->base + MSTR_INT_STATUS);
+ /* Ignore disabled interrupts */
+ int_status &= readl(ctrl->base + MSTR_INT_EN);
+
/* PIO mode handling */
if (ctrl->xfer.dir == QSPI_WRITE) {
if (int_status & WR_FIFO_EMPTY)
@@ -647,6 +666,30 @@
return ret;
}
+static int qcom_qspi_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
+{
+ /*
+ * If qcom_qspi_can_dma() is going to return false we don't need to
+ * adjust anything.
+ */
+ if (op->data.nbytes <= QSPI_MAX_BYTES_FIFO)
+ return 0;
+
+ /*
+ * When reading, the transfer needs to be a multiple of 4 bytes so
+ * shrink the transfer if that's not true. The caller will then do a
+ * second transfer to finish things up.
+ */
+ if (op->data.dir == SPI_MEM_DATA_IN && (op->data.nbytes & 0x3))
+ op->data.nbytes &= ~0x3;
+
+ return 0;
+}
+
+static const struct spi_controller_mem_ops qcom_qspi_mem_ops = {
+ .adjust_op_size = qcom_qspi_adjust_op_size,
+};
+
static int qcom_qspi_probe(struct platform_device *pdev)
{
int ret;
@@ -731,6 +774,7 @@
if (of_property_read_bool(pdev->dev.of_node, "iommus"))
master->can_dma = qcom_qspi_can_dma;
master->auto_runtime_pm = true;
+ master->mem_ops = &qcom_qspi_mem_ops;
ret = devm_pm_opp_set_clkname(&pdev->dev, "core");
if (ret)
