u-boot/drivers/iommu/iommu-uclass.c
Caleb Connolly b185618011 iommu: dont fail silently
When attempting to probe a device which has an associated IOMMU, if the
IOMMU device can't be found (no driver, disabled driver, driver failed
to probe, etc) then we currently fail to probe the device with no
discernable error.

If we fail to hook the device up to its IOMMU, we should make sure that
the user knows about it. Write some better error messages for
dev_iommu_enable() to facilitate this.

Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>
2024-01-18 12:18:48 -05:00

153 lines
3.3 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2021 Mark Kettenis <kettenis@openbsd.org>
*/
#define LOG_CATEGORY UCLASS_IOMMU
#include <common.h>
#include <dm.h>
#include <iommu.h>
#include <malloc.h>
#include <phys2bus.h>
#include <asm/io.h>
#if (CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA))
#if CONFIG_IS_ENABLED(PCI)
static int dev_pci_iommu_enable(struct udevice *dev)
{
struct udevice *parent = dev->parent;
struct udevice *dev_iommu;
u32 *iommu_map;
u32 iommu_map_mask, length, phandle, rid, rid_base;
int i, count, len, ret;
while (parent) {
len = dev_read_size(parent, "iommu-map");
if (len > 0)
break;
parent = parent->parent;
}
if (len <= 0)
return 0;
iommu_map = malloc(len);
if (!iommu_map)
return -ENOMEM;
count = len / sizeof(u32);
ret = dev_read_u32_array(parent, "iommu-map", iommu_map, count);
if (ret < 0) {
free(iommu_map);
return 0;
}
iommu_map_mask = dev_read_u32_default(parent, "iommu-map-mask", ~0);
rid = (dm_pci_get_bdf(dev) >> 8) & iommu_map_mask;
/* Loop over entries until mapping is found. */
for (i = 0; i < count; i += 4) {
rid_base = iommu_map[i];
phandle = iommu_map[i + 1];
length = iommu_map[i + 3];
if (rid < rid_base || rid >= rid_base + length)
continue;
ret = uclass_get_device_by_phandle_id(UCLASS_IOMMU, phandle,
&dev_iommu);
if (ret) {
debug("%s: uclass_get_device_by_ofnode failed: %d\n",
__func__, ret);
free(iommu_map);
return ret;
}
dev->iommu = dev_iommu;
break;
}
free(iommu_map);
return 0;
}
#endif
int dev_iommu_enable(struct udevice *dev)
{
struct ofnode_phandle_args args;
struct udevice *dev_iommu;
const struct iommu_ops *ops;
int i, count, ret = 0;
count = dev_count_phandle_with_args(dev, "iommus",
"#iommu-cells", 0);
for (i = 0; i < count; i++) {
ret = dev_read_phandle_with_args(dev, "iommus",
"#iommu-cells", 0, i, &args);
if (ret) {
log_err("%s: Failed to parse 'iommus' property for '%s': %d\n",
__func__, dev->name, ret);
return ret;
}
ret = uclass_get_device_by_ofnode(UCLASS_IOMMU, args.node,
&dev_iommu);
if (ret) {
log_err("%s: Failed to find IOMMU device for '%s': %d\n",
__func__, dev->name, ret);
return ret;
}
dev->iommu = dev_iommu;
if (dev->parent && dev->parent->iommu == dev_iommu)
continue;
ops = device_get_ops(dev->iommu);
if (ops && ops->connect) {
ret = ops->connect(dev);
if (ret) {
log_err("%s: Failed to connect '%s' to IOMMU '%s': %d\n",
__func__, dev->name, dev->iommu->name, ret);
return ret;
}
}
}
#if CONFIG_IS_ENABLED(PCI)
if (count < 0 && device_is_on_pci_bus(dev))
return dev_pci_iommu_enable(dev);
#endif
return 0;
}
#endif
dma_addr_t dev_iommu_dma_map(struct udevice *dev, void *addr, size_t size)
{
const struct iommu_ops *ops;
if (dev->iommu) {
ops = device_get_ops(dev->iommu);
if (ops && ops->map)
return ops->map(dev->iommu, addr, size);
}
return dev_phys_to_bus(dev, virt_to_phys(addr));
}
void dev_iommu_dma_unmap(struct udevice *dev, dma_addr_t addr, size_t size)
{
const struct iommu_ops *ops;
if (dev->iommu) {
ops = device_get_ops(dev->iommu);
if (ops && ops->unmap)
ops->unmap(dev->iommu, addr, size);
}
}
UCLASS_DRIVER(iommu) = {
.id = UCLASS_IOMMU,
.name = "iommu",
};