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Subject[PATCH v8 1/5] drm/i915/gsc: add gsc as a mei auxiliary device
Date
From: Tomas Winkler <tomas.winkler@intel.com>

GSC is a graphics system controller, it provides
a chassis controller for graphics discrete cards.

There are two MEI interfaces in GSC: HECI1 and HECI2.

Both interfaces are on the BAR0 at offsets 0x00258000 and 0x00259000.
GSC is a GT Engine (class 4: instance 6). HECI1 interrupt is signaled
via bit 15 and HECI2 via bit 14 in the interrupt register.

This patch exports GSC as auxiliary device for mei driver to bind to
for HECI2 interface.

CC: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Vitaly Lubart <vitaly.lubart@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
---
V4: add header to the MAINTAINERS file
drop empty line
V5: rebase
V6: rebase, drop redundant assignments
V7: add Greg KH Reviewed-by
V8: rename dev_priv variable to i915,
drop data from irq_set_chip_data,
switch intel_gsc_irq_handler with gsc_irq_handler to have same prefixes in the external API,
add error prints and use right drm print functions
---
MAINTAINERS | 1 +
drivers/gpu/drm/i915/Kconfig | 1 +
drivers/gpu/drm/i915/Makefile | 3 +
drivers/gpu/drm/i915/gt/intel_gsc.c | 199 +++++++++++++++++++++++
drivers/gpu/drm/i915/gt/intel_gsc.h | 37 +++++
drivers/gpu/drm/i915/gt/intel_gt.c | 3 +
drivers/gpu/drm/i915/gt/intel_gt.h | 5 +
drivers/gpu/drm/i915/gt/intel_gt_irq.c | 13 ++
drivers/gpu/drm/i915/gt/intel_gt_regs.h | 1 +
drivers/gpu/drm/i915/gt/intel_gt_types.h | 2 +
drivers/gpu/drm/i915/i915_drv.h | 8 +
drivers/gpu/drm/i915/i915_pci.c | 3 +-
drivers/gpu/drm/i915/i915_reg.h | 2 +
drivers/gpu/drm/i915/intel_device_info.h | 2 +
include/linux/mei_aux.h | 19 +++
15 files changed, 298 insertions(+), 1 deletion(-)
create mode 100644 drivers/gpu/drm/i915/gt/intel_gsc.c
create mode 100644 drivers/gpu/drm/i915/gt/intel_gsc.h
create mode 100644 include/linux/mei_aux.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 78b8f2038ce8..e95dad2b628c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9810,6 +9810,7 @@ S: Supported
F: Documentation/driver-api/mei/*
F: drivers/misc/mei/
F: drivers/watchdog/mei_wdt.c
+F: include/linux/mei_aux.h
F: include/linux/mei_cl_bus.h
F: include/uapi/linux/mei.h
F: samples/mei/*
diff --git a/drivers/gpu/drm/i915/Kconfig b/drivers/gpu/drm/i915/Kconfig
index 42b5400f0fef..b51dbe3c09ee 100644
--- a/drivers/gpu/drm/i915/Kconfig
+++ b/drivers/gpu/drm/i915/Kconfig
@@ -29,6 +29,7 @@ config DRM_I915
select VMAP_PFN
select DRM_TTM
select DRM_BUDDY
+ select AUXILIARY_BUS
help
Choose this option if you have a system that has "Intel Graphics
Media Accelerator" or "HD Graphics" integrated graphics,
diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
index 226dbef5f64a..e40ba71b3cdd 100644
--- a/drivers/gpu/drm/i915/Makefile
+++ b/drivers/gpu/drm/i915/Makefile
@@ -195,6 +195,9 @@ i915-y += gt/uc/intel_uc.o \
gt/uc/intel_huc_debugfs.o \
gt/uc/intel_huc_fw.o

+# graphics system controller (GSC) support
+i915-y += gt/intel_gsc.o
+
# modesetting core code
i915-y += \
display/hsw_ips.o \
diff --git a/drivers/gpu/drm/i915/gt/intel_gsc.c b/drivers/gpu/drm/i915/gt/intel_gsc.c
new file mode 100644
index 000000000000..a3a73c234bad
--- /dev/null
+++ b/drivers/gpu/drm/i915/gt/intel_gsc.c
@@ -0,0 +1,199 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright(c) 2019-2022, Intel Corporation. All rights reserved.
+ */
+
+#include <linux/irq.h>
+#include <linux/mei_aux.h>
+#include "i915_reg.h"
+#include "i915_drv.h"
+#include "gt/intel_gt.h"
+#include "intel_gsc.h"
+
+#define GSC_BAR_LENGTH 0x00000FFC
+
+static void gsc_irq_mask(struct irq_data *d)
+{
+ /* generic irq handling */
+}
+
+static void gsc_irq_unmask(struct irq_data *d)
+{
+ /* generic irq handling */
+}
+
+static struct irq_chip gsc_irq_chip = {
+ .name = "gsc_irq_chip",
+ .irq_mask = gsc_irq_mask,
+ .irq_unmask = gsc_irq_unmask,
+};
+
+static int gsc_irq_init(int irq)
+{
+ irq_set_chip_and_handler_name(irq, &gsc_irq_chip,
+ handle_simple_irq, "gsc_irq_handler");
+
+ return irq_set_chip_data(irq, NULL);
+}
+
+struct intel_gsc_def {
+ const char *name;
+ unsigned long bar;
+ size_t bar_size;
+};
+
+/* gscfi (graphics system controller firmware interface) resources */
+static const struct intel_gsc_def intel_gsc_def_dg1[] = {
+ {
+ /* HECI1 not yet implemented. */
+ },
+ {
+ .name = "mei-gscfi",
+ .bar = GSC_DG1_HECI2_BASE,
+ .bar_size = GSC_BAR_LENGTH,
+ }
+};
+
+static void intel_gsc_release_dev(struct device *dev)
+{
+ struct auxiliary_device *aux_dev = to_auxiliary_dev(dev);
+ struct mei_aux_device *adev = auxiliary_dev_to_mei_aux_dev(aux_dev);
+
+ kfree(adev);
+}
+
+static void intel_gsc_destroy_one(struct intel_gsc_intf *intf)
+{
+ if (intf->adev) {
+ auxiliary_device_delete(&intf->adev->aux_dev);
+ auxiliary_device_uninit(&intf->adev->aux_dev);
+ intf->adev = NULL;
+ }
+ if (intf->irq >= 0)
+ irq_free_desc(intf->irq);
+ intf->irq = -1;
+}
+
+static void intel_gsc_init_one(struct drm_i915_private *i915,
+ struct intel_gsc_intf *intf,
+ unsigned int intf_id)
+{
+ struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
+ struct mei_aux_device *adev;
+ struct auxiliary_device *aux_dev;
+ const struct intel_gsc_def *def;
+ int ret;
+
+ intf->irq = -1;
+ intf->id = intf_id;
+
+ if (intf_id == 0 && !HAS_HECI_PXP(i915))
+ return;
+
+ def = &intel_gsc_def_dg1[intf_id];
+
+ intf->irq = irq_alloc_desc(0);
+ if (intf->irq < 0) {
+ dev_err(&pdev->dev, "gsc irq error %d\n", intf->irq);
+ return;
+ }
+
+ ret = gsc_irq_init(intf->irq);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "gsc irq init failed %d\n", ret);
+ goto fail;
+ }
+
+ adev = kzalloc(sizeof(*adev), GFP_KERNEL);
+ if (!adev)
+ goto fail;
+
+ adev->irq = intf->irq;
+ adev->bar.parent = &pdev->resource[0];
+ adev->bar.start = def->bar + pdev->resource[0].start;
+ adev->bar.end = adev->bar.start + def->bar_size - 1;
+ adev->bar.flags = IORESOURCE_MEM;
+ adev->bar.desc = IORES_DESC_NONE;
+
+ aux_dev = &adev->aux_dev;
+ aux_dev->name = def->name;
+ aux_dev->id = (pci_domain_nr(pdev->bus) << 16) |
+ PCI_DEVID(pdev->bus->number, pdev->devfn);
+ aux_dev->dev.parent = &pdev->dev;
+ aux_dev->dev.release = intel_gsc_release_dev;
+
+ ret = auxiliary_device_init(aux_dev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "gsc aux init failed %d\n", ret);
+ kfree(adev);
+ goto fail;
+ }
+
+ ret = auxiliary_device_add(aux_dev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "gsc aux add failed %d\n", ret);
+ /* adev will be freed with the put_device() and .release sequence */
+ auxiliary_device_uninit(aux_dev);
+ goto fail;
+ }
+ intf->adev = adev;
+
+ return;
+fail:
+ intel_gsc_destroy_one(intf);
+}
+
+static void gsc_irq_handler(struct intel_gt *gt, unsigned int intf_id)
+{
+ int ret;
+
+ if (intf_id >= INTEL_GSC_NUM_INTERFACES) {
+ drm_warn_once(&gt->i915->drm, "GSC irq: intf_id %d is out of range", intf_id);
+ return;
+ }
+
+ if (!HAS_HECI_GSC(gt->i915)) {
+ drm_warn_once(&gt->i915->drm, "GSC irq: not supported");
+ return;
+ }
+
+ if (gt->gsc.intf[intf_id].irq <= 0) {
+ drm_err_ratelimited(&gt->i915->drm, "GSC irq: irq not set");
+ return;
+ }
+
+ ret = generic_handle_irq(gt->gsc.intf[intf_id].irq);
+ if (ret)
+ drm_err_ratelimited(&gt->i915->drm, "error handling GSC irq: %d\n", ret);
+}
+
+void intel_gsc_irq_handler(struct intel_gt *gt, u32 iir)
+{
+ if (iir & GSC_IRQ_INTF(0))
+ gsc_irq_handler(gt, 0);
+ if (iir & GSC_IRQ_INTF(1))
+ gsc_irq_handler(gt, 1);
+}
+
+void intel_gsc_init(struct intel_gsc *gsc, struct drm_i915_private *i915)
+{
+ unsigned int i;
+
+ if (!HAS_HECI_GSC(i915))
+ return;
+
+ for (i = 0; i < INTEL_GSC_NUM_INTERFACES; i++)
+ intel_gsc_init_one(i915, &gsc->intf[i], i);
+}
+
+void intel_gsc_fini(struct intel_gsc *gsc)
+{
+ struct intel_gt *gt = gsc_to_gt(gsc);
+ unsigned int i;
+
+ if (!HAS_HECI_GSC(gt->i915))
+ return;
+
+ for (i = 0; i < INTEL_GSC_NUM_INTERFACES; i++)
+ intel_gsc_destroy_one(&gsc->intf[i]);
+}
diff --git a/drivers/gpu/drm/i915/gt/intel_gsc.h b/drivers/gpu/drm/i915/gt/intel_gsc.h
new file mode 100644
index 000000000000..68582f912b21
--- /dev/null
+++ b/drivers/gpu/drm/i915/gt/intel_gsc.h
@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright(c) 2019-2022, Intel Corporation. All rights reserved.
+ */
+#ifndef __INTEL_GSC_DEV_H__
+#define __INTEL_GSC_DEV_H__
+
+#include <linux/types.h>
+
+struct drm_i915_private;
+struct intel_gt;
+struct mei_aux_device;
+
+#define INTEL_GSC_NUM_INTERFACES 2
+/*
+ * The HECI1 bit corresponds to bit15 and HECI2 to bit14.
+ * The reason for this is to allow growth for more interfaces in the future.
+ */
+#define GSC_IRQ_INTF(_x) BIT(15 - (_x))
+
+/**
+ * struct intel_gsc - graphics security controller
+ * @intf : gsc interface
+ */
+struct intel_gsc {
+ struct intel_gsc_intf {
+ struct mei_aux_device *adev;
+ int irq;
+ unsigned int id;
+ } intf[INTEL_GSC_NUM_INTERFACES];
+};
+
+void intel_gsc_init(struct intel_gsc *gsc, struct drm_i915_private *dev_priv);
+void intel_gsc_fini(struct intel_gsc *gsc);
+void intel_gsc_irq_handler(struct intel_gt *gt, u32 iir);
+
+#endif /* __INTEL_GSC_DEV_H__ */
diff --git a/drivers/gpu/drm/i915/gt/intel_gt.c b/drivers/gpu/drm/i915/gt/intel_gt.c
index e8403fa53909..18961d154956 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt.c
@@ -446,6 +446,8 @@ void intel_gt_chipset_flush(struct intel_gt *gt)

void intel_gt_driver_register(struct intel_gt *gt)
{
+ intel_gsc_init(&gt->gsc, gt->i915);
+
intel_rps_driver_register(&gt->rps);

intel_gt_debugfs_register(gt);
@@ -766,6 +768,7 @@ void intel_gt_driver_unregister(struct intel_gt *gt)
intel_wakeref_t wakeref;

intel_rps_driver_unregister(&gt->rps);
+ intel_gsc_fini(&gt->gsc);

intel_pxp_fini(&gt->pxp);

diff --git a/drivers/gpu/drm/i915/gt/intel_gt.h b/drivers/gpu/drm/i915/gt/intel_gt.h
index 2dad46c3eff2..6ba817c02baa 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt.h
+++ b/drivers/gpu/drm/i915/gt/intel_gt.h
@@ -34,6 +34,11 @@ static inline struct intel_gt *huc_to_gt(struct intel_huc *huc)
return container_of(huc, struct intel_gt, uc.huc);
}

+static inline struct intel_gt *gsc_to_gt(struct intel_gsc *gsc)
+{
+ return container_of(gsc, struct intel_gt, gsc);
+}
+
void intel_gt_init_early(struct intel_gt *gt, struct drm_i915_private *i915);
void __intel_gt_init_early(struct intel_gt *gt, struct drm_i915_private *i915);
int intel_gt_assign_ggtt(struct intel_gt *gt);
diff --git a/drivers/gpu/drm/i915/gt/intel_gt_irq.c b/drivers/gpu/drm/i915/gt/intel_gt_irq.c
index 983264e10e0a..08bf2796c3c1 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_irq.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt_irq.c
@@ -68,6 +68,9 @@ gen11_other_irq_handler(struct intel_gt *gt, const u8 instance,
if (instance == OTHER_KCR_INSTANCE)
return intel_pxp_irq_handler(&gt->pxp, iir);

+ if (instance == OTHER_GSC_INSTANCE)
+ return intel_gsc_irq_handler(gt, iir);
+
WARN_ONCE(1, "unhandled other interrupt instance=0x%x, iir=0x%x\n",
instance, iir);
}
@@ -182,6 +185,8 @@ void gen11_gt_irq_reset(struct intel_gt *gt)
/* Disable RCS, BCS, VCS and VECS class engines. */
intel_uncore_write(uncore, GEN11_RENDER_COPY_INTR_ENABLE, 0);
intel_uncore_write(uncore, GEN11_VCS_VECS_INTR_ENABLE, 0);
+ if (HAS_HECI_GSC(gt->i915))
+ intel_uncore_write(uncore, GEN11_GUNIT_CSME_INTR_ENABLE, 0);

/* Restore masks irqs on RCS, BCS, VCS and VECS engines. */
intel_uncore_write(uncore, GEN11_RCS0_RSVD_INTR_MASK, ~0);
@@ -195,6 +200,8 @@ void gen11_gt_irq_reset(struct intel_gt *gt)
intel_uncore_write(uncore, GEN11_VECS0_VECS1_INTR_MASK, ~0);
if (HAS_ENGINE(gt, VECS2) || HAS_ENGINE(gt, VECS3))
intel_uncore_write(uncore, GEN12_VECS2_VECS3_INTR_MASK, ~0);
+ if (HAS_HECI_GSC(gt->i915))
+ intel_uncore_write(uncore, GEN11_GUNIT_CSME_INTR_MASK, ~0);

intel_uncore_write(uncore, GEN11_GPM_WGBOXPERF_INTR_ENABLE, 0);
intel_uncore_write(uncore, GEN11_GPM_WGBOXPERF_INTR_MASK, ~0);
@@ -209,6 +216,7 @@ void gen11_gt_irq_postinstall(struct intel_gt *gt)
{
struct intel_uncore *uncore = gt->uncore;
u32 irqs = GT_RENDER_USER_INTERRUPT;
+ const u32 gsc_mask = GSC_IRQ_INTF(0) | GSC_IRQ_INTF(1);
u32 dmask;
u32 smask;

@@ -225,6 +233,9 @@ void gen11_gt_irq_postinstall(struct intel_gt *gt)
/* Enable RCS, BCS, VCS and VECS class interrupts. */
intel_uncore_write(uncore, GEN11_RENDER_COPY_INTR_ENABLE, dmask);
intel_uncore_write(uncore, GEN11_VCS_VECS_INTR_ENABLE, dmask);
+ if (HAS_HECI_GSC(gt->i915))
+ intel_uncore_write(uncore, GEN11_GUNIT_CSME_INTR_ENABLE,
+ gsc_mask);

/* Unmask irqs on RCS, BCS, VCS and VECS engines. */
intel_uncore_write(uncore, GEN11_RCS0_RSVD_INTR_MASK, ~smask);
@@ -238,6 +249,8 @@ void gen11_gt_irq_postinstall(struct intel_gt *gt)
intel_uncore_write(uncore, GEN11_VECS0_VECS1_INTR_MASK, ~dmask);
if (HAS_ENGINE(gt, VECS2) || HAS_ENGINE(gt, VECS3))
intel_uncore_write(uncore, GEN12_VECS2_VECS3_INTR_MASK, ~dmask);
+ if (HAS_HECI_GSC(gt->i915))
+ intel_uncore_write(uncore, GEN11_GUNIT_CSME_INTR_MASK, 0);
/*
* RPS interrupts will get enabled/disabled on demand when RPS itself
* is enabled/disabled.
diff --git a/drivers/gpu/drm/i915/gt/intel_gt_regs.h b/drivers/gpu/drm/i915/gt/intel_gt_regs.h
index a6f0220c2e9f..427f91900afc 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_regs.h
+++ b/drivers/gpu/drm/i915/gt/intel_gt_regs.h
@@ -944,6 +944,7 @@ enum {
#define OTHER_GUC_INSTANCE 0
#define OTHER_GTPM_INSTANCE 1
#define OTHER_KCR_INSTANCE 4
+#define OTHER_GSC_INSTANCE 6

#define GEN11_INTR_IDENTITY_REG(x) _MMIO(0x190060 + ((x) * 4))

diff --git a/drivers/gpu/drm/i915/gt/intel_gt_types.h b/drivers/gpu/drm/i915/gt/intel_gt_types.h
index f20687796490..5556d55f76ea 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_types.h
+++ b/drivers/gpu/drm/i915/gt/intel_gt_types.h
@@ -16,6 +16,7 @@
#include <linux/workqueue.h>

#include "uc/intel_uc.h"
+#include "intel_gsc.h"

#include "i915_vma.h"
#include "intel_engine_types.h"
@@ -72,6 +73,7 @@ struct intel_gt {
struct i915_ggtt *ggtt;

struct intel_uc uc;
+ struct intel_gsc gsc;

struct mutex tlb_invalidate_lock;

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 418091484e02..168bf32deea0 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1327,6 +1327,14 @@ IS_SUBPLATFORM(const struct drm_i915_private *i915,

#define HAS_DMC(dev_priv) (INTEL_INFO(dev_priv)->display.has_dmc)

+#define HAS_HECI_PXP(dev_priv) \
+ (INTEL_INFO(dev_priv)->has_heci_pxp)
+
+#define HAS_HECI_GSCFI(dev_priv) \
+ (INTEL_INFO(dev_priv)->has_heci_gscfi)
+
+#define HAS_HECI_GSC(dev_priv) (HAS_HECI_PXP(dev_priv) || HAS_HECI_GSCFI(dev_priv))
+
#define HAS_MSO(i915) (DISPLAY_VER(i915) >= 12)

#define HAS_RUNTIME_PM(dev_priv) (INTEL_INFO(dev_priv)->has_runtime_pm)
diff --git a/drivers/gpu/drm/i915/i915_pci.c b/drivers/gpu/drm/i915/i915_pci.c
index 8246cbe9b01d..ef54917a0000 100644
--- a/drivers/gpu/drm/i915/i915_pci.c
+++ b/drivers/gpu/drm/i915/i915_pci.c
@@ -901,7 +901,8 @@ static const struct intel_device_info rkl_info = {
.has_llc = 0, \
.has_pxp = 0, \
.has_snoop = 1, \
- .is_dgfx = 1
+ .is_dgfx = 1, \
+ .has_heci_gscfi = 1

static const struct intel_device_info dg1_info = {
GEN12_FEATURES,
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 4ea1713e6b60..8afe4af6c844 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -974,6 +974,8 @@
#define GEN11_VEBOX2_RING_BASE 0x1d8000
#define XEHP_VEBOX3_RING_BASE 0x1e8000
#define XEHP_VEBOX4_RING_BASE 0x1f8000
+#define GSC_DG1_HECI1_BASE 0x00258000
+#define GSC_DG1_HECI2_BASE 0x00259000
#define BLT_RING_BASE 0x22000


diff --git a/drivers/gpu/drm/i915/intel_device_info.h b/drivers/gpu/drm/i915/intel_device_info.h
index 27dcfe6f2429..fa75f464cb01 100644
--- a/drivers/gpu/drm/i915/intel_device_info.h
+++ b/drivers/gpu/drm/i915/intel_device_info.h
@@ -135,6 +135,8 @@ enum intel_ppgtt_type {
func(has_reset_engine); \
func(has_global_mocs); \
func(has_gt_uc); \
+ func(has_heci_pxp); \
+ func(has_heci_gscfi); \
func(has_guc_deprivilege); \
func(has_l3_dpf); \
func(has_llc); \
diff --git a/include/linux/mei_aux.h b/include/linux/mei_aux.h
new file mode 100644
index 000000000000..587f25128848
--- /dev/null
+++ b/include/linux/mei_aux.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2022, Intel Corporation. All rights reserved.
+ */
+#ifndef _LINUX_MEI_AUX_H
+#define _LINUX_MEI_AUX_H
+
+#include <linux/auxiliary_bus.h>
+
+struct mei_aux_device {
+ struct auxiliary_device aux_dev;
+ int irq;
+ struct resource bar;
+};
+
+#define auxiliary_dev_to_mei_aux_dev(auxiliary_dev) \
+ container_of(auxiliary_dev, struct mei_aux_device, aux_dev)
+
+#endif /* _LINUX_MEI_AUX_H */
--
2.32.0
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