usb: dwc3-msm: Add support for IOMMU
On platforms where an IOMMU is used, create a mapping and attach
the platform device to it. This will allow DMA translations through
the IOMMU.
This mapping requires setting the DOMAIN_ATTR_ATOMIC flag, as USB
tends to call DMA map/unmap operations in interrupt context. Due to
the additional clock/regulator resource requirements this imposes,
we should not leave the MMU attached when USB is not in use. Hence
perform the MMU attach/detach operation in conjunction with the
resume/suspend functions when the cable is connected/removed.
Change-Id: I98326ba4ffacbf203969037ffa994ec825d74c78
Signed-off-by: Jack Pham <jackp@codeaurora.org>
diff --git a/drivers/usb/dwc3/dwc3-msm.c b/drivers/usb/dwc3/dwc3-msm.c
index f456f12..8d2b429 100644
--- a/drivers/usb/dwc3/dwc3-msm.c
+++ b/drivers/usb/dwc3/dwc3-msm.c
@@ -21,6 +21,8 @@
#include <linux/pm_runtime.h>
#include <linux/ratelimit.h>
#include <linux/interrupt.h>
+#include <asm/dma-iommu.h>
+#include <linux/iommu.h>
#include <linux/ioport.h>
#include <linux/clk.h>
#include <linux/io.h>
@@ -155,6 +157,7 @@
void __iomem *base;
void __iomem *ahb2phy_base;
struct platform_device *dwc3;
+ struct dma_iommu_mapping *iommu_map;
const struct usb_ep_ops *original_ep_ops[DWC3_ENDPOINTS_NUM];
struct list_head req_complete_list;
struct clk *xo_clk;
@@ -1004,7 +1007,7 @@
int num_trbs = (dep->direction) ? (2 * (req->num_bufs) + 2)
: (req->num_bufs + 1);
- dep->trb_dma_pool = dma_pool_create(ep->name, dwc->dev,
+ dep->trb_dma_pool = dma_pool_create(ep->name, dwc->sysdev,
num_trbs * sizeof(struct dwc3_trb),
num_trbs * sizeof(struct dwc3_trb), 0);
if (!dep->trb_dma_pool) {
@@ -2091,6 +2094,9 @@
dev_dbg(mdwc->dev, "%s: power collapse\n", __func__);
dwc3_msm_config_gdsc(mdwc, 0);
clk_disable_unprepare(mdwc->sleep_clk);
+
+ if (mdwc->iommu_map)
+ arm_iommu_detach_device(mdwc->dev);
}
/* Remove bus voting */
@@ -2236,6 +2242,16 @@
PWR_EVNT_POWERDOWN_IN_P3_MASK, 1);
mdwc->lpm_flags &= ~MDWC3_POWER_COLLAPSE;
+
+ if (mdwc->iommu_map) {
+ ret = arm_iommu_attach_device(mdwc->dev,
+ mdwc->iommu_map);
+ if (ret)
+ dev_err(mdwc->dev, "IOMMU attach failed (%d)\n",
+ ret);
+ else
+ dev_dbg(mdwc->dev, "attached to IOMMU\n");
+ }
}
atomic_set(&dwc->in_lpm, 0);
@@ -2766,6 +2782,41 @@
return ret;
}
+#define SMMU_BASE 0x10000000 /* Device address range base */
+#define SMMU_SIZE 0x40000000 /* Device address range size */
+
+static int dwc3_msm_init_iommu(struct dwc3_msm *mdwc)
+{
+ struct device_node *node = mdwc->dev->of_node;
+ int atomic_ctx = 1;
+ int ret;
+
+ if (!of_property_read_bool(node, "iommus"))
+ return 0;
+
+ mdwc->iommu_map = arm_iommu_create_mapping(&platform_bus_type,
+ SMMU_BASE, SMMU_SIZE);
+ if (IS_ERR_OR_NULL(mdwc->iommu_map)) {
+ ret = PTR_ERR(mdwc->iommu_map) ?: -ENODEV;
+ dev_err(mdwc->dev, "Failed to create IOMMU mapping (%d)\n",
+ ret);
+ return ret;
+ }
+ dev_dbg(mdwc->dev, "IOMMU mapping created: %pK\n", mdwc->iommu_map);
+
+ ret = iommu_domain_set_attr(mdwc->iommu_map->domain, DOMAIN_ATTR_ATOMIC,
+ &atomic_ctx);
+ if (ret) {
+ dev_err(mdwc->dev, "IOMMU set atomic attribute failed (%d)\n",
+ ret);
+ arm_iommu_release_mapping(mdwc->iommu_map);
+ mdwc->iommu_map = NULL;
+ return ret;
+ }
+
+ return 0;
+}
+
static ssize_t mode_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
@@ -3070,12 +3121,16 @@
dwc3_set_notifier(&dwc3_msm_notify_event);
+ ret = dwc3_msm_init_iommu(mdwc);
+ if (ret)
+ goto err;
+
/* Assumes dwc3 is the first DT child of dwc3-msm */
dwc3_node = of_get_next_available_child(node, NULL);
if (!dwc3_node) {
dev_err(&pdev->dev, "failed to find dwc3 child\n");
ret = -ENODEV;
- goto err;
+ goto uninit_iommu;
}
ret = of_platform_populate(node, NULL, NULL, &pdev->dev);
@@ -3083,7 +3138,7 @@
dev_err(&pdev->dev,
"failed to add create dwc3 core\n");
of_node_put(dwc3_node);
- goto err;
+ goto uninit_iommu;
}
mdwc->dwc3 = of_find_device_by_node(dwc3_node);
@@ -3194,6 +3249,9 @@
platform_device_put(mdwc->dwc3);
if (mdwc->bus_perf_client)
msm_bus_scale_unregister_client(mdwc->bus_perf_client);
+uninit_iommu:
+ if (mdwc->iommu_map)
+ arm_iommu_release_mapping(mdwc->iommu_map);
err:
return ret;
}
@@ -3271,6 +3329,12 @@
dwc3_msm_config_gdsc(mdwc, 0);
+ if (mdwc->iommu_map) {
+ if (!atomic_read(&dwc->in_lpm))
+ arm_iommu_detach_device(mdwc->dev);
+ arm_iommu_release_mapping(mdwc->iommu_map);
+ }
+
return 0;
}