From: Alex Deucher <alexander.deucher@xxxxxxx>
The doorbell aperture is a PCI BAR whose pages can be
mapped to compute resources for things like wptrs
for userspace queues.
This patch maps the BAR and sets up a simple allocator
to allocate pages from the BAR.
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
---
drivers/gpu/drm/radeon/cik.c | 38 +++++++++++++
drivers/gpu/drm/radeon/radeon.h | 21 +++++++
drivers/gpu/drm/radeon/radeon_device.c | 94 ++++++++++++++++++++++++++++++++
3 files changed, 153 insertions(+), 0 deletions(-)
diff --git a/drivers/gpu/drm/radeon/cik.c b/drivers/gpu/drm/radeon/cik.c
index bb7dbc4..5c28fa5 100644
--- a/drivers/gpu/drm/radeon/cik.c
+++ b/drivers/gpu/drm/radeon/cik.c
@@ -121,6 +121,44 @@ u32 cik_get_xclk(struct radeon_device *rdev)
return reference_clock;
}
+/**
+ * cik_mm_rdoorbell - read a doorbell dword
+ *
+ * @rdev: radeon_device pointer
+ * @offset: byte offset into the aperture
+ *
+ * Returns the value in the doorbell aperture at the
+ * requested offset (CIK).
+ */
+u32 cik_mm_rdoorbell(struct radeon_device *rdev, u32 offset)
+{
+ if (offset < rdev->doorbell.size) {
+ return readl(((void __iomem *)rdev->doorbell.ptr) + offset);
+ } else {
+ DRM_ERROR("reading beyond doorbell aperture: 0x%08x!\n", offset);
+ return 0;
+ }
+}
+
+/**
+ * cik_mm_wdoorbell - write a doorbell dword
+ *
+ * @rdev: radeon_device pointer
+ * @offset: byte offset into the aperture
+ * @v: value to write
+ *
+ * Writes @v to the doorbell aperture at the
+ * requested offset (CIK).
+ */
+void cik_mm_wdoorbell(struct radeon_device *rdev, u32 offset, u32 v)
+{
+ if (offset < rdev->doorbell.size) {
+ writel(v, ((void __iomem *)rdev->doorbell.ptr) + offset);
+ } else {
+ DRM_ERROR("writing beyond doorbell aperture: 0x%08x!\n", offset);
+ }
+}
+
#define BONAIRE_IO_MC_REGS_SIZE 36
static const u32 bonaire_io_mc_regs[BONAIRE_IO_MC_REGS_SIZE][2] =
diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index ad4e68a..a2a3430 100644
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -556,6 +556,20 @@ struct radeon_scratch {
int radeon_scratch_get(struct radeon_device *rdev, uint32_t *reg);
void radeon_scratch_free(struct radeon_device *rdev, uint32_t reg);
+/*
+ * GPU doorbell structures, functions & helpers
+ */
+struct radeon_doorbell {
+ u32 num_pages;
+ bool free[1024];
+ /* doorbell mmio */
+ resource_size_t base;
+ resource_size_t size;
+ void __iomem *ptr;
+};
+
+int radeon_doorbell_get(struct radeon_device *rdev, u32 *page);
+void radeon_doorbell_free(struct radeon_device *rdev, u32 doorbell);
/*
* IRQS.
@@ -1711,6 +1725,7 @@ struct radeon_device {
struct radeon_gart gart;
struct radeon_mode_info mode_info;
struct radeon_scratch scratch;
+ struct radeon_doorbell doorbell;
struct radeon_mman mman;
struct radeon_fence_driver fence_drv[RADEON_NUM_RINGS];
wait_queue_head_t fence_queue;
@@ -1784,6 +1799,9 @@ void r100_mm_wreg(struct radeon_device *rdev, uint32_t reg, uint32_t v,
u32 r100_io_rreg(struct radeon_device *rdev, u32 reg);
void r100_io_wreg(struct radeon_device *rdev, u32 reg, u32 v);
+u32 cik_mm_rdoorbell(struct radeon_device *rdev, u32 offset);
+void cik_mm_wdoorbell(struct radeon_device *rdev, u32 offset, u32 v);
+
/*
* Cast helper
*/
@@ -1833,6 +1851,9 @@ void r100_io_wreg(struct radeon_device *rdev, u32 reg, u32 v);
#define RREG32_IO(reg) r100_io_rreg(rdev, (reg))
#define WREG32_IO(reg, v) r100_io_wreg(rdev, (reg), (v))
+#define RDOORBELL32(offset) cik_mm_rdoorbell(rdev, (offset))
+#define WDOORBELL32(offset, v) cik_mm_wdoorbell(rdev, (offset), (v))
+
/*
* Indirect registers accessor
*/
diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c
index 4e97ff7..82335e3 100644
--- a/drivers/gpu/drm/radeon/radeon_device.c
+++ b/drivers/gpu/drm/radeon/radeon_device.c
@@ -232,6 +232,94 @@ void radeon_scratch_free(struct radeon_device *rdev, uint32_t reg)
}
/*
+ * GPU doorbell aperture helpers function.
+ */
+/**
+ * radeon_doorbell_init - Init doorbell driver information.
+ *
+ * @rdev: radeon_device pointer
+ *
+ * Init doorbell driver information (CIK)
+ * Returns 0 on success, error on failure.
+ */
+int radeon_doorbell_init(struct radeon_device *rdev)
+{
+ int i;
+
+ /* doorbell bar mapping */
+ rdev->doorbell.base = pci_resource_start(rdev->pdev, 2);
+ rdev->doorbell.size = pci_resource_len(rdev->pdev, 2);
+
+ /* limit to 4 MB for now */
+ if (rdev->doorbell.size > (4 * 1024 * 1024))
+ rdev->doorbell.size = 4 * 1024 * 1024;
+
+ rdev->doorbell.ptr = ioremap(rdev->doorbell.base, rdev->doorbell.size);
+ if (rdev->doorbell.ptr == NULL) {
+ return -ENOMEM;
+ }
+ DRM_INFO("doorbell mmio base: 0x%08X\n", (uint32_t)rdev->doorbell.base);
+ DRM_INFO("doorbell mmio size: %u\n", (unsigned)rdev->doorbell.size);
+
+ rdev->doorbell.num_pages = rdev->doorbell.size / PAGE_SIZE;
+
+ for (i = 0; i < rdev->doorbell.num_pages; i++) {
+ rdev->doorbell.free[i] = true;
+ }
+ return 0;
+}
+
+/**
+ * radeon_doorbell_fini - Tear down doorbell driver information.
+ *
+ * @rdev: radeon_device pointer
+ *
+ * Tear down doorbell driver information (CIK)
+ */
+void radeon_doorbell_fini(struct radeon_device *rdev)
+{
+ iounmap(rdev->doorbell.ptr);
+ rdev->doorbell.ptr = NULL;
+}
+
+/**
+ * radeon_doorbell_get - Allocate a doorbell page
+ *
+ * @rdev: radeon_device pointer
+ * @doorbell: doorbell page number
+ *
+ * Allocate a doorbell page for use by the driver (all asics).
+ * Returns 0 on success or -EINVAL on failure.
+ */
+int radeon_doorbell_get(struct radeon_device *rdev, u32 *doorbell)
+{
+ int i;
+
+ for (i = 0; i < rdev->doorbell.num_pages; i++) {
+ if (rdev->doorbell.free[i]) {
+ rdev->doorbell.free[i] = false;
+ *doorbell = i;
+ return 0;
+ }
+ }
+ return -EINVAL;
+}
+
+/**
+ * radeon_doorbell_free - Free a doorbell page
+ *
+ * @rdev: radeon_device pointer
+ * @doorbell: doorbell page number
+ *
+ * Free a doorbell page allocated for use by the driver (all asics)
+ */
+void radeon_doorbell_free(struct radeon_device *rdev, u32 doorbell)
+{
+ if (doorbell < rdev->doorbell.num_pages)
+ rdev->doorbell.free[doorbell] = true;
+}
+
+/*
* radeon_wb_*()
* Writeback is the the method by which the the GPU updates special pages
* in memory with the status of certain GPU events (fences, ring pointers,
@@ -1162,6 +1250,10 @@ int radeon_device_init(struct radeon_device *rdev,
DRM_INFO("register mmio base: 0x%08X\n", (uint32_t)rdev->rmmio_base);
DRM_INFO("register mmio size: %u\n", (unsigned)rdev->rmmio_size);
+ /* doorbell bar mapping */
+ if (rdev->family >= CHIP_BONAIRE)
+ radeon_doorbell_init(rdev);
+
/* io port mapping */
for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
if (pci_resource_flags(rdev->pdev, i) & IORESOURCE_IO) {
@@ -1239,6 +1331,8 @@ void radeon_device_fini(struct radeon_device *rdev)
rdev->rio_mem = NULL;
iounmap(rdev->rmmio);
rdev->rmmio = NULL;
+ if (rdev->family >= CHIP_BONAIRE)
+ radeon_doorbell_fini(rdev);
radeon_debugfs_remove_files(rdev);
}
--
1.7.7.5
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