Re: [Intel-gfx] [PATCH] drm/i915: abstraction for iosf to compile on all archs

[Lucas De Marchi]

On Fri, Oct 22, 2021 at 12:07:04AM +0530, Mullati Siva wrote:

From: "Mullati, Siva" <siva.mull...@intel.com>

As Non-x86 architectures won't get compiled asm\iosf,
abstarcting them to make compile for all archs.

I noticed a typo here, then thought we should expand a little bit. What
about something like below?

The asm/iosf_mbi.h header is x86-only. Let's make IOSF_MBI kconfig
selection conditional to x86 and provide a header with stubs for other
architectures. This helps getting i915 available for other
architectures in future.


Reviewed-by: Lucas De Marchi <lucas.demar...@intel.com>

but it would be good to wait for an a-b/r-b from Jani as well.

thanks
Lucas De Marchi

Signed-off-by: Mullati, Siva <siva.mull...@intel.com>
---
drivers/gpu/drm/i915/Kconfig         |  2 +-
drivers/gpu/drm/i915/i915_iosf_mbi.h | 42 ++++++++++++++++++++++++++++
drivers/gpu/drm/i915/intel_uncore.c  |  2 +-
drivers/gpu/drm/i915/vlv_sideband.c  |  3 +-
4 files changed, 45 insertions(+), 4 deletions(-)
create mode 100644 drivers/gpu/drm/i915/i915_iosf_mbi.h

diff --git a/drivers/gpu/drm/i915/Kconfig b/drivers/gpu/drm/i915/Kconfig
index bf041b26ffec..8bea99622dd5 100644
--- a/drivers/gpu/drm/i915/Kconfig
+++ b/drivers/gpu/drm/i915/Kconfig
@@ -21,7 +21,7 @@ config DRM_I915
        select ACPI_VIDEO if ACPI
        select ACPI_BUTTON if ACPI
        select SYNC_FILE
-       select IOSF_MBI
+       select IOSF_MBI if X86
        select CRC32
        select SND_HDA_I915 if SND_HDA_CORE
        select CEC_CORE if CEC_NOTIFIER
diff --git a/drivers/gpu/drm/i915/i915_iosf_mbi.h 
b/drivers/gpu/drm/i915/i915_iosf_mbi.h
new file mode 100644
index 000000000000..01eed11e4a94
--- /dev/null
+++ b/drivers/gpu/drm/i915/i915_iosf_mbi.h
@@ -0,0 +1,42 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2013-2021 Intel Corporation
+ */
+
+#ifndef __I915_IOSF_MBI_H__
+#define __I915_IOSF_MBI_H__
+
+#if IS_ENABLED(CONFIG_IOSF_MBI)
+#include <asm/iosf_mbi.h>
+#else
+
+/* Stubs to compile for all non-x86 archs */
+#define MBI_PMIC_BUS_ACCESS_BEGIN       1
+#define MBI_PMIC_BUS_ACCESS_END         2
+
+struct notifier_block;
+
+static inline void iosf_mbi_punit_acquire(void) {}
+static inline void iosf_mbi_punit_release(void) {}
+static inline void iosf_mbi_assert_punit_acquired(void) {}
+
+static inline
+int iosf_mbi_register_pmic_bus_access_notifier(struct notifier_block *nb)
+{
+       return 0;
+}
+
+static inline int
+iosf_mbi_unregister_pmic_bus_access_notifier_unlocked(struct notifier_block 
*nb)
+{
+       return 0;
+}
+
+static inline
+int iosf_mbi_unregister_pmic_bus_access_notifier(struct notifier_block *nb)
+{
+       return 0;
+}
+#endif
+
+#endif /* __I915_IOSF_MBI_H__ */
diff --git a/drivers/gpu/drm/i915/intel_uncore.c 
b/drivers/gpu/drm/i915/intel_uncore.c
index e072054adac5..722910d02b5f 100644
--- a/drivers/gpu/drm/i915/intel_uncore.c
+++ b/drivers/gpu/drm/i915/intel_uncore.c
@@ -22,11 +22,11 @@
 */

#include <linux/pm_runtime.h>
-#include <asm/iosf_mbi.h>

#include "gt/intel_lrc_reg.h" /* for shadow reg list */

#include "i915_drv.h"
+#include "i915_iosf_mbi.h"
#include "i915_trace.h"
#include "i915_vgpu.h"
#include "intel_pm.h"
diff --git a/drivers/gpu/drm/i915/vlv_sideband.c 
b/drivers/gpu/drm/i915/vlv_sideband.c
index 35380738a951..ed2ac5752ac4 100644
--- a/drivers/gpu/drm/i915/vlv_sideband.c
+++ b/drivers/gpu/drm/i915/vlv_sideband.c
@@ -3,9 +3,8 @@
 * Copyright © 2013-2021 Intel Corporation
 */

-#include <asm/iosf_mbi.h>
-
#include "i915_drv.h"
+#include "i915_iosf_mbi.h"
#include "vlv_sideband.h"

/*
--
2.33.0