[PATCH V6 10/10] dmaengine: qcom_hidma: add MSI support for interrupts
Sinan Kaya
okaya at codeaurora.org
Wed Oct 19 10:51:52 PDT 2016
The interrupts can now be delivered as platform MSI interrupts on newer
platforms. The code looks for a new OF and ACPI strings in order to enable
the functionality.
Signed-off-by: Sinan Kaya <okaya at codeaurora.org>
---
drivers/dma/qcom/hidma.c | 143 ++++++++++++++++++++++++++++++++++++++++++--
drivers/dma/qcom/hidma.h | 2 +
drivers/dma/qcom/hidma_ll.c | 8 +++
3 files changed, 147 insertions(+), 6 deletions(-)
diff --git a/drivers/dma/qcom/hidma.c b/drivers/dma/qcom/hidma.c
index 4adf249..2ea6917 100644
--- a/drivers/dma/qcom/hidma.c
+++ b/drivers/dma/qcom/hidma.c
@@ -56,6 +56,7 @@
#include <linux/irq.h>
#include <linux/atomic.h>
#include <linux/pm_runtime.h>
+#include <linux/msi.h>
#include "../dmaengine.h"
#include "hidma.h"
@@ -70,6 +71,7 @@
#define HIDMA_ERR_INFO_SW 0xFF
#define HIDMA_ERR_CODE_UNEXPECTED_TERMINATE 0x0
#define HIDMA_NR_DEFAULT_DESC 10
+#define HIDMA_MSI_INTS 11
static inline struct hidma_dev *to_hidma_dev(struct dma_device *dmadev)
{
@@ -553,6 +555,15 @@ static irqreturn_t hidma_chirq_handler(int chirq, void *arg)
return hidma_ll_inthandler(chirq, lldev);
}
+static irqreturn_t hidma_chirq_handler_msi(int chirq, void *arg)
+{
+ struct hidma_lldev **lldevp = arg;
+ struct hidma_dev *dmadev = to_hidma_dev_from_lldev(lldevp);
+
+ return hidma_ll_inthandler_msi(chirq, *lldevp,
+ 1 << (chirq - dmadev->msi_virqbase));
+}
+
static ssize_t hidma_show_values(struct device *dev,
struct device_attribute *attr, char *buf)
{
@@ -604,6 +615,104 @@ static int hidma_sysfs_init(struct hidma_dev *dev)
return device_create_file(dev->ddev.dev, dev->chid_attrs);
}
+#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
+static void hidma_write_msi_msg(struct msi_desc *desc, struct msi_msg *msg)
+{
+ struct device *dev = msi_desc_to_dev(desc);
+ struct hidma_dev *dmadev = dev_get_drvdata(dev);
+
+ if (!desc->platform.msi_index) {
+ writel(msg->address_lo, dmadev->dev_evca + 0x118);
+ writel(msg->address_hi, dmadev->dev_evca + 0x11C);
+ writel(msg->data, dmadev->dev_evca + 0x120);
+ }
+}
+#endif
+
+static void hidma_free_msis(struct hidma_dev *dmadev)
+{
+#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
+ struct device *dev = dmadev->ddev.dev;
+ struct msi_desc *desc;
+
+ /* free allocated MSI interrupts above */
+ for_each_msi_entry(desc, dev)
+ devm_free_irq(dev, desc->irq, &dmadev->lldev);
+
+ platform_msi_domain_free_irqs(dev);
+#endif
+}
+
+static int hidma_request_msi(struct hidma_dev *dmadev,
+ struct platform_device *pdev)
+{
+#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
+ int rc;
+ struct msi_desc *desc;
+ struct msi_desc *failed_desc = NULL;
+
+ rc = platform_msi_domain_alloc_irqs(&pdev->dev, HIDMA_MSI_INTS,
+ hidma_write_msi_msg);
+ if (rc)
+ return rc;
+
+ for_each_msi_entry(desc, &pdev->dev) {
+ if (!desc->platform.msi_index)
+ dmadev->msi_virqbase = desc->irq;
+
+ rc = devm_request_irq(&pdev->dev, desc->irq,
+ hidma_chirq_handler_msi,
+ 0, "qcom-hidma-msi",
+ &dmadev->lldev);
+ if (rc) {
+ failed_desc = desc;
+ break;
+ }
+ }
+
+ if (rc) {
+ /* free allocated MSI interrupts above */
+ for_each_msi_entry(desc, &pdev->dev) {
+ if (desc == failed_desc)
+ break;
+ devm_free_irq(&pdev->dev, desc->irq,
+ &dmadev->lldev);
+ }
+ } else {
+ /* Add callback to free MSIs on teardown */
+ hidma_ll_setup_irq(dmadev->lldev, true);
+
+ }
+ if (rc)
+ dev_warn(&pdev->dev,
+ "failed to request MSI irq, falling back to wired IRQ\n");
+ return rc;
+#else
+ return -EINVAL;
+#endif
+}
+
+static bool hidma_msi_capable(struct device *dev)
+{
+ struct acpi_device *adev = ACPI_COMPANION(dev);
+ const char *of_compat;
+ int ret = -EINVAL;
+
+ if (!adev || acpi_disabled) {
+ ret = device_property_read_string(dev, "compatible",
+ &of_compat);
+ if (ret)
+ return false;
+
+ ret = strcmp(of_compat, "qcom,hidma-1.1");
+ } else {
+#ifdef CONFIG_ACPI
+ ret = strcmp(acpi_device_hid(adev), "QCOM8062");
+#endif
+ }
+ return ret == 0;
+}
+
static int hidma_probe(struct platform_device *pdev)
{
struct hidma_dev *dmadev;
@@ -613,6 +722,7 @@ static int hidma_probe(struct platform_device *pdev)
void __iomem *evca;
void __iomem *trca;
int rc;
+ bool msi;
pm_runtime_set_autosuspend_delay(&pdev->dev, HIDMA_AUTOSUSPEND_TIMEOUT);
pm_runtime_use_autosuspend(&pdev->dev);
@@ -674,6 +784,12 @@ static int hidma_probe(struct platform_device *pdev)
dmadev->ddev.device_terminate_all = hidma_terminate_all;
dmadev->ddev.copy_align = 8;
+ /*
+ * Determine the MSI capability of the platform. Old HW doesn't
+ * support MSI.
+ */
+ msi = hidma_msi_capable(&pdev->dev);
+
device_property_read_u32(&pdev->dev, "desc-count",
&dmadev->nr_descriptors);
@@ -702,10 +818,17 @@ static int hidma_probe(struct platform_device *pdev)
goto dmafree;
}
- rc = devm_request_irq(&pdev->dev, chirq, hidma_chirq_handler, 0,
- "qcom-hidma", dmadev->lldev);
- if (rc)
- goto uninit;
+ platform_set_drvdata(pdev, dmadev);
+ if (msi)
+ rc = hidma_request_msi(dmadev, pdev);
+
+ if (!msi || rc) {
+ hidma_ll_setup_irq(dmadev->lldev, false);
+ rc = devm_request_irq(&pdev->dev, chirq, hidma_chirq_handler,
+ 0, "qcom-hidma", dmadev->lldev);
+ if (rc)
+ goto uninit;
+ }
INIT_LIST_HEAD(&dmadev->ddev.channels);
rc = hidma_chan_init(dmadev, 0);
@@ -721,12 +844,14 @@ static int hidma_probe(struct platform_device *pdev)
hidma_debug_init(dmadev);
hidma_sysfs_init(dmadev);
dev_info(&pdev->dev, "HI-DMA engine driver registration complete\n");
- platform_set_drvdata(pdev, dmadev);
pm_runtime_mark_last_busy(dmadev->ddev.dev);
pm_runtime_put_autosuspend(dmadev->ddev.dev);
return 0;
uninit:
+ if (msi)
+ hidma_free_msis(dmadev);
+
hidma_debug_uninit(dmadev);
hidma_ll_uninit(dmadev->lldev);
dmafree:
@@ -744,7 +869,11 @@ static int hidma_remove(struct platform_device *pdev)
pm_runtime_get_sync(dmadev->ddev.dev);
dma_async_device_unregister(&dmadev->ddev);
- devm_free_irq(dmadev->ddev.dev, dmadev->irq, dmadev->lldev);
+ if (!dmadev->lldev->msi_support)
+ devm_free_irq(dmadev->ddev.dev, dmadev->irq, dmadev->lldev);
+ else
+ hidma_free_msis(dmadev);
+
tasklet_kill(&dmadev->task);
hidma_sysfs_uninit(dmadev);
hidma_debug_uninit(dmadev);
@@ -761,12 +890,14 @@ static int hidma_remove(struct platform_device *pdev)
#if IS_ENABLED(CONFIG_ACPI)
static const struct acpi_device_id hidma_acpi_ids[] = {
{"QCOM8061"},
+ {"QCOM8062"},
{},
};
#endif
static const struct of_device_id hidma_match[] = {
{.compatible = "qcom,hidma-1.0",},
+ {.compatible = "qcom,hidma-1.1",},
{},
};
MODULE_DEVICE_TABLE(of, hidma_match);
diff --git a/drivers/dma/qcom/hidma.h b/drivers/dma/qcom/hidma.h
index 7b40014..c7d0142 100644
--- a/drivers/dma/qcom/hidma.h
+++ b/drivers/dma/qcom/hidma.h
@@ -115,6 +115,7 @@ struct hidma_dev {
int irq;
int chidx;
u32 nr_descriptors;
+ int msi_virqbase;
struct hidma_lldev *lldev;
void __iomem *dev_trca;
@@ -156,6 +157,7 @@ struct hidma_lldev *hidma_ll_init(struct device *dev, u32 max_channels,
u8 chidx);
int hidma_ll_uninit(struct hidma_lldev *llhndl);
irqreturn_t hidma_ll_inthandler(int irq, void *arg);
+irqreturn_t hidma_ll_inthandler_msi(int irq, void *arg, int cause);
void hidma_cleanup_pending_tre(struct hidma_lldev *llhndl, u8 err_info,
u8 err_code);
int hidma_debug_init(struct hidma_dev *dmadev);
diff --git a/drivers/dma/qcom/hidma_ll.c b/drivers/dma/qcom/hidma_ll.c
index 999abda..d5c520f 100644
--- a/drivers/dma/qcom/hidma_ll.c
+++ b/drivers/dma/qcom/hidma_ll.c
@@ -457,6 +457,14 @@ irqreturn_t hidma_ll_inthandler(int chirq, void *arg)
return IRQ_HANDLED;
}
+irqreturn_t hidma_ll_inthandler_msi(int chirq, void *arg, int cause)
+{
+ struct hidma_lldev *lldev = arg;
+
+ hidma_ll_int_handler_internal(lldev, cause);
+ return IRQ_HANDLED;
+}
+
int hidma_ll_enable(struct hidma_lldev *lldev)
{
u32 val;
--
1.9.1
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