Re: [PATCH 01/10] drm/i915/spi: add spi device for discrete graphics

Jani Nikula
2023-09-11T15:42:07Z

On Sun, 10 Sep 2023, Alexander Usyskin <alexander.usyskin@intel.com> wrote:
> From: Jani Nikula <jani.nikula@intel.com>

I'm almost certain I did not write this patch originally. The authorship
may have been changed accidentally along the way, but it's not mine.

BR,
Jani.

>
> Enable access to internal spi on DGFX devices via a child device.
> The spi child device is exposed via auxiliary bus.
>
> CC: Rodrigo Vivi <rodrigo.vivi@intel.com>
> CC: Lucas De Marchi <lucas.demarchi@intel.com>
> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
> Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
> ---
> drivers/gpu/drm/i915/Makefile | 3 ++
> drivers/gpu/drm/i915/i915_driver.c | 7 +++
> drivers/gpu/drm/i915/i915_drv.h | 4 ++
> drivers/gpu/drm/i915/i915_reg.h | 1 +
> drivers/gpu/drm/i915/spi/intel_spi.c | 68 ++++++++++++++++++++++++++++
> drivers/gpu/drm/i915/spi/intel_spi.h | 26 +++++++++++
> 6 files changed, 109 insertions(+)
> create mode 100644 drivers/gpu/drm/i915/spi/intel_spi.c
> create mode 100644 drivers/gpu/drm/i915/spi/intel_spi.h
>
> diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
> index 79f65eff6bb2..f16870ad2615 100644
> --- a/drivers/gpu/drm/i915/Makefile
> +++ b/drivers/gpu/drm/i915/Makefile
> @@ -222,6 +222,9 @@ i915-y += \
> # graphics system controller (GSC) support
> i915-y += gt/intel_gsc.o
>
> +# graphics spi device (DGFX) support
> +i915-y += spi/intel_spi.o
> +
> # graphics hardware monitoring (HWMON) support
> i915-$(CONFIG_HWMON) += i915_hwmon.o
>
> diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c
> index f8dbee7a5af7..aeeb34a8dde2 100644
> --- a/drivers/gpu/drm/i915/i915_driver.c
> +++ b/drivers/gpu/drm/i915/i915_driver.c
> @@ -80,6 +80,8 @@
> #include "soc/intel_dram.h"
> #include "soc/intel_gmch.h"
>
> +#include "spi/intel_spi.h"
> +
> #include "i915_debugfs.h"
> #include "i915_driver.h"
> #include "i915_drm_client.h"
> @@ -666,6 +668,8 @@ static void i915_driver_unregister(struct drm_i915_private *dev_priv)
>
> i915_hwmon_unregister(dev_priv);
>
> + intel_spi_fini(&dev_priv->spi);
> +
> i915_perf_unregister(dev_priv);
> i915_pmu_unregister(dev_priv);
>
> @@ -1133,6 +1137,9 @@ static int i915_drm_suspend_late(struct drm_device *dev, bool hibernation)
>
> i915_gem_suspend_late(dev_priv);
>
> +
> + intel_spi_init(&dev_priv->spi, dev_priv);
> +
> for_each_gt(gt, dev_priv, i)
> intel_uncore_suspend(gt->uncore);
>
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 87ffc477c3b1..abc601200cb4 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -51,6 +51,8 @@
>
> #include "soc/intel_pch.h"
>
> +#include "spi/intel_spi.h"
> +
> #include "i915_drm_client.h"
> #include "i915_gem.h"
> #include "i915_gpu_error.h"
> @@ -315,6 +317,8 @@ struct drm_i915_private {
>
> struct i915_perf perf;
>
> + struct intel_spi spi;
> +
> struct i915_hwmon *hwmon;
>
> /* Abstract the submission mechanism (legacy ringbuffer or execlists) away */
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index e00e4d569ba9..0f8b01495b77 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -930,6 +930,7 @@
> #define DG2_GSC_HECI2_BASE 0x00374000
> #define MTL_GSC_HECI1_BASE 0x00116000
> #define MTL_GSC_HECI2_BASE 0x00117000
> +#define GEN12_GUNIT_SPI_BASE 0x00102040
>
> #define HECI_H_CSR(base) _MMIO((base) + 0x4)
> #define HECI_H_CSR_IE REG_BIT(0)
> diff --git a/drivers/gpu/drm/i915/spi/intel_spi.c b/drivers/gpu/drm/i915/spi/intel_spi.c
> new file mode 100644
> index 000000000000..9eb5ab6bc4b9
> --- /dev/null
> +++ b/drivers/gpu/drm/i915/spi/intel_spi.c
> @@ -0,0 +1,68 @@
> +// SPDX-License-Identifier: MIT
> +/*
> + * Copyright(c) 2019-2022, Intel Corporation. All rights reserved.
> + */
> +
> +#include <linux/irq.h>
> +#include "i915_reg.h"
> +#include "i915_drv.h"
> +#include "spi/intel_spi.h"
> +
> +#define GEN12_GUNIT_SPI_SIZE 0x80
> +
> +static void i915_spi_release_dev(struct device *dev)
> +{
> +}
> +
> +void intel_spi_init(struct intel_spi *spi, struct drm_i915_private *dev_priv)
> +{
> + struct pci_dev *pdev = to_pci_dev(dev_priv->drm.dev);
> + struct auxiliary_device *aux_dev = &spi->aux_dev;
> + int ret;
> +
> + /* Only the DGFX devices have internal SPI */
> + if (!IS_DGFX(dev_priv))
> + return;
> +
> + spi->bar.parent = &pdev->resource[0];
> + spi->bar.start = GEN12_GUNIT_SPI_BASE + pdev->resource[0].start;
> + spi->bar.end = spi->bar.start + GEN12_GUNIT_SPI_SIZE - 1;
> + spi->bar.flags = IORESOURCE_MEM;
> + spi->bar.desc = IORES_DESC_NONE;
> +
> + aux_dev->name = "spi";
> + 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 = i915_spi_release_dev;
> +
> + ret = auxiliary_device_init(aux_dev);
> + if (ret) {
> + dev_err(&pdev->dev, "i915-spi aux init failed %d\n", ret);
> + return;
> + }
> +
> + ret = auxiliary_device_add(aux_dev);
> + if (ret) {
> + dev_err(&pdev->dev, "i915-spi aux add failed %d\n", ret);
> + auxiliary_device_uninit(aux_dev);
> + return;
> + }
> +
> + spi->i915 = dev_priv;
> +}
> +
> +void intel_spi_fini(struct intel_spi *spi)
> +{
> + struct pci_dev *pdev;
> +
> + if (!spi->i915)
> + return;
> +
> + pdev = to_pci_dev(spi->i915->drm.dev);
> +
> + dev_dbg(&pdev->dev, "removing i915-spi cell\n");
> +
> + auxiliary_device_delete(&spi->aux_dev);
> + auxiliary_device_uninit(&spi->aux_dev);
> +}
> diff --git a/drivers/gpu/drm/i915/spi/intel_spi.h b/drivers/gpu/drm/i915/spi/intel_spi.h
> new file mode 100644
> index 000000000000..a58bf79dcbc9
> --- /dev/null
> +++ b/drivers/gpu/drm/i915/spi/intel_spi.h
> @@ -0,0 +1,26 @@
> +/* SPDX-License-Identifier: MIT */
> +/*
> + * Copyright(c) 2019-2022, Intel Corporation. All rights reserved.
> + */
> +
> +#ifndef __INTEL_SPI_DEV_H__
> +#define __INTEL_SPI_DEV_H__
> +
> +#include <linux/auxiliary_bus.h>
> +
> +struct drm_i915_private;
> +
> +struct intel_spi {
> + struct auxiliary_device aux_dev;
> + struct drm_i915_private *i915;
> + struct resource bar;
> +};
> +
> +#define auxiliary_dev_to_intel_spi_dev(auxiliary_dev) \
> + container_of(auxiliary_dev, struct intel_spi, aux_dev)
> +
> +void intel_spi_init(struct intel_spi *spi, struct drm_i915_private *i915);
> +
> +void intel_spi_fini(struct intel_spi *spi);
> +
> +#endif /* __INTEL_SPI_DEV_H__ */

--
Jani Nikula, Intel Open Source Graphics Center