[PATCH] i3c: mipi-i3c-hci: Use physical device pointer with DMA API
Jarkko Nikula
jarkko.nikula at linux.intel.com
Mon Feb 3 06:55:12 PST 2025
DMA transfer faults on Intel hardware when the IOMMU is enabled and
driver initialization will fail when attempting to do the first transfer:
DMAR: DRHD: handling fault status reg 2
DMAR: [DMA Read NO_PASID] Request device [00:11.0] fault addr 0x676e3000 [fault reason 0x71] SM: Present bit in first-level paging entry
i3c mipi-i3c-hci.0: ring 0: Transfer Aborted
mipi-i3c-hci mipi-i3c-hci.0: probe with driver mipi-i3c-hci failed with error -62
Reason for this is that the IOMMU setup is done for the physical devices
only and not for the virtual I3C Controller device object.
Therefore use the pointer to a physical device object with the DMA API.
Reported-by: Prabhakaran, Krishna <krishna.prabhakaran at intel.com>
Signed-off-by: Jarkko Nikula <jarkko.nikula at linux.intel.com>
---
drivers/i3c/master/mipi-i3c-hci/dma.c | 45 ++++++++++++++++++---------
1 file changed, 31 insertions(+), 14 deletions(-)
diff --git a/drivers/i3c/master/mipi-i3c-hci/dma.c b/drivers/i3c/master/mipi-i3c-hci/dma.c
index 491dfe70b660..57c044b5264b 100644
--- a/drivers/i3c/master/mipi-i3c-hci/dma.c
+++ b/drivers/i3c/master/mipi-i3c-hci/dma.c
@@ -14,6 +14,7 @@
#include <linux/errno.h>
#include <linux/i3c/master.h>
#include <linux/io.h>
+#include <linux/pci.h>
#include "hci.h"
#include "cmd.h"
@@ -138,6 +139,7 @@ struct hci_rh_data {
};
struct hci_rings_data {
+ struct device *sysdev;
unsigned int total;
struct hci_rh_data headers[] __counted_by(total);
};
@@ -165,20 +167,20 @@ static void hci_dma_cleanup(struct i3c_hci *hci)
rh_reg_write(IBI_SETUP, 0);
if (rh->xfer)
- dma_free_coherent(&hci->master.dev,
+ dma_free_coherent(rings->sysdev,
rh->xfer_struct_sz * rh->xfer_entries,
rh->xfer, rh->xfer_dma);
if (rh->resp)
- dma_free_coherent(&hci->master.dev,
+ dma_free_coherent(rings->sysdev,
rh->resp_struct_sz * rh->xfer_entries,
rh->resp, rh->resp_dma);
kfree(rh->src_xfers);
if (rh->ibi_status)
- dma_free_coherent(&hci->master.dev,
+ dma_free_coherent(rings->sysdev,
rh->ibi_status_sz * rh->ibi_status_entries,
rh->ibi_status, rh->ibi_status_dma);
if (rh->ibi_data_dma)
- dma_unmap_single(&hci->master.dev, rh->ibi_data_dma,
+ dma_unmap_single(rings->sysdev, rh->ibi_data_dma,
rh->ibi_chunk_sz * rh->ibi_chunks_total,
DMA_FROM_DEVICE);
kfree(rh->ibi_data);
@@ -194,11 +196,23 @@ static int hci_dma_init(struct i3c_hci *hci)
{
struct hci_rings_data *rings;
struct hci_rh_data *rh;
+ struct device *sysdev;
u32 regval;
unsigned int i, nr_rings, xfers_sz, resps_sz;
unsigned int ibi_status_ring_sz, ibi_data_ring_sz;
int ret;
+ /*
+ * Set pointer to a physical device that does DMA and has IOMMU setup
+ * done for it in case of enabled IOMMU and use it with the DMA API.
+ * Here such device is either
+ * "mipi-i3c-hci" platform device (OF/ACPI enumeration) parent or
+ * grandparent (PCI enumeration).
+ */
+ sysdev = hci->master.dev.parent;
+ if (sysdev->parent && dev_is_pci(sysdev->parent))
+ sysdev = sysdev->parent;
+
regval = rhs_reg_read(CONTROL);
nr_rings = FIELD_GET(MAX_HEADER_COUNT_CAP, regval);
dev_info(&hci->master.dev, "%d DMA rings available\n", nr_rings);
@@ -213,6 +227,7 @@ static int hci_dma_init(struct i3c_hci *hci)
return -ENOMEM;
hci->io_data = rings;
rings->total = nr_rings;
+ rings->sysdev = sysdev;
regval = FIELD_PREP(MAX_HEADER_COUNT, rings->total);
rhs_reg_write(CONTROL, regval);
@@ -239,9 +254,9 @@ static int hci_dma_init(struct i3c_hci *hci)
xfers_sz = rh->xfer_struct_sz * rh->xfer_entries;
resps_sz = rh->resp_struct_sz * rh->xfer_entries;
- rh->xfer = dma_alloc_coherent(&hci->master.dev, xfers_sz,
+ rh->xfer = dma_alloc_coherent(rings->sysdev, xfers_sz,
&rh->xfer_dma, GFP_KERNEL);
- rh->resp = dma_alloc_coherent(&hci->master.dev, resps_sz,
+ rh->resp = dma_alloc_coherent(rings->sysdev, resps_sz,
&rh->resp_dma, GFP_KERNEL);
rh->src_xfers =
kmalloc_array(rh->xfer_entries, sizeof(*rh->src_xfers),
@@ -295,16 +310,16 @@ static int hci_dma_init(struct i3c_hci *hci)
ibi_data_ring_sz = rh->ibi_chunk_sz * rh->ibi_chunks_total;
rh->ibi_status =
- dma_alloc_coherent(&hci->master.dev, ibi_status_ring_sz,
+ dma_alloc_coherent(rings->sysdev, ibi_status_ring_sz,
&rh->ibi_status_dma, GFP_KERNEL);
rh->ibi_data = kmalloc(ibi_data_ring_sz, GFP_KERNEL);
ret = -ENOMEM;
if (!rh->ibi_status || !rh->ibi_data)
goto err_out;
rh->ibi_data_dma =
- dma_map_single(&hci->master.dev, rh->ibi_data,
+ dma_map_single(rings->sysdev, rh->ibi_data,
ibi_data_ring_sz, DMA_FROM_DEVICE);
- if (dma_mapping_error(&hci->master.dev, rh->ibi_data_dma)) {
+ if (dma_mapping_error(rings->sysdev, rh->ibi_data_dma)) {
rh->ibi_data_dma = 0;
ret = -ENOMEM;
goto err_out;
@@ -342,6 +357,7 @@ static int hci_dma_init(struct i3c_hci *hci)
static void hci_dma_unmap_xfer(struct i3c_hci *hci,
struct hci_xfer *xfer_list, unsigned int n)
{
+ struct hci_rings_data *rings = hci->io_data;
struct hci_xfer *xfer;
unsigned int i;
@@ -349,7 +365,7 @@ static void hci_dma_unmap_xfer(struct i3c_hci *hci,
xfer = xfer_list + i;
if (!xfer->data)
continue;
- dma_unmap_single(&hci->master.dev,
+ dma_unmap_single(rings->sysdev,
xfer->data_dma, xfer->data_len,
xfer->rnw ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
}
@@ -393,13 +409,13 @@ static int hci_dma_queue_xfer(struct i3c_hci *hci,
if (xfer->data) {
buf = xfer->bounce_buf ? xfer->bounce_buf : xfer->data;
xfer->data_dma =
- dma_map_single(&hci->master.dev,
+ dma_map_single(rings->sysdev,
buf,
xfer->data_len,
xfer->rnw ?
DMA_FROM_DEVICE :
DMA_TO_DEVICE);
- if (dma_mapping_error(&hci->master.dev,
+ if (dma_mapping_error(rings->sysdev,
xfer->data_dma)) {
hci_dma_unmap_xfer(hci, xfer_list, i);
return -ENOMEM;
@@ -586,6 +602,7 @@ static void hci_dma_recycle_ibi_slot(struct i3c_hci *hci,
static void hci_dma_process_ibi(struct i3c_hci *hci, struct hci_rh_data *rh)
{
+ struct hci_rings_data *rings = hci->io_data;
struct i3c_dev_desc *dev;
struct i3c_hci_dev_data *dev_data;
struct hci_dma_dev_ibi_data *dev_ibi;
@@ -696,7 +713,7 @@ static void hci_dma_process_ibi(struct i3c_hci *hci, struct hci_rh_data *rh)
* rh->ibi_chunk_sz;
if (first_part > ibi_size)
first_part = ibi_size;
- dma_sync_single_for_cpu(&hci->master.dev, ring_ibi_data_dma,
+ dma_sync_single_for_cpu(rings->sysdev, ring_ibi_data_dma,
first_part, DMA_FROM_DEVICE);
memcpy(slot->data, ring_ibi_data, first_part);
@@ -705,7 +722,7 @@ static void hci_dma_process_ibi(struct i3c_hci *hci, struct hci_rh_data *rh)
/* we wrap back to the start and copy remaining data */
ring_ibi_data = rh->ibi_data;
ring_ibi_data_dma = rh->ibi_data_dma;
- dma_sync_single_for_cpu(&hci->master.dev, ring_ibi_data_dma,
+ dma_sync_single_for_cpu(rings->sysdev, ring_ibi_data_dma,
ibi_size - first_part, DMA_FROM_DEVICE);
memcpy(slot->data + first_part, ring_ibi_data,
ibi_size - first_part);
--
2.47.2
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