Re: [PATCH v2 01/13] intel_gna: add driver module
From: Andy Shevchenko
Date: Wed Mar 24 2021 - 15:32:05 EST
On Wed, Mar 24, 2021 at 8:38 PM Maciej Kwapulinski
<maciej.kwapulinski@xxxxxxxxxxxxxxx> wrote:
>
> From: Tomasz Jankowski <tomasz1.jankowski@xxxxxxxxx>
>
> Add a new PCI driver for Intel(R) Gaussian & Neural Accelerator
> with basic support like module loading and unloading. The full
> function of the driver will be added by further changes.
>
> Signed-off-by: Tomasz Jankowski <tomasz1.jankowski@xxxxxxxxx>
> Tested-by: Savo Novakovic <savox.novakovic@xxxxxxxxx>
> Co-developed-by: Jianxun Zhang <jianxun.zhang@xxxxxxxxxxxxxxx>
> Signed-off-by: Jianxun Zhang <jianxun.zhang@xxxxxxxxxxxxxxx>
> Co-developed-by: Maciej Kwapulinski <maciej.kwapulinski@xxxxxxxxxxxxxxx>
> Signed-off-by: Maciej Kwapulinski <maciej.kwapulinski@xxxxxxxxxxxxxxx>
> ---
> Documentation/misc-devices/index.rst | 1 +
> Documentation/misc-devices/intel/gna.rst | 48 ++++++
> .../userspace-api/ioctl/ioctl-number.rst | 1 +
> MAINTAINERS | 7 +
> drivers/misc/Kconfig | 1 +
> drivers/misc/Makefile | 1 +
> drivers/misc/intel/gna/Kbuild | 5 +
> drivers/misc/intel/gna/Kconfig | 13 ++
> drivers/misc/intel/gna/gna_device.c | 74 +++++++++
> drivers/misc/intel/gna/gna_device.h | 36 ++++
> drivers/misc/intel/gna/gna_driver.c | 39 +++++
> drivers/misc/intel/gna/gna_driver.h | 15 ++
What is the point now to have gna/gna_, I guess the latter should go?
> include/uapi/misc/intel/gna.h | 155 ++++++++++++++++++
> 13 files changed, 396 insertions(+)
> create mode 100644 Documentation/misc-devices/intel/gna.rst
> create mode 100644 drivers/misc/intel/gna/Kbuild
> create mode 100644 drivers/misc/intel/gna/Kconfig
> create mode 100644 drivers/misc/intel/gna/gna_device.c
> create mode 100644 drivers/misc/intel/gna/gna_device.h
> create mode 100644 drivers/misc/intel/gna/gna_driver.c
> create mode 100644 drivers/misc/intel/gna/gna_driver.h
> create mode 100644 include/uapi/misc/intel/gna.h
>
> diff --git a/Documentation/misc-devices/index.rst b/Documentation/misc-devices/index.rst
> index 64420b3314fe..1b187ee121b0 100644
> --- a/Documentation/misc-devices/index.rst
> +++ b/Documentation/misc-devices/index.rst
> @@ -19,6 +19,7 @@ fit into other categories.
> bh1770glc
> eeprom
> c2port
> + intel/gna
Shouldn't it preserve ordering?
> ibmvmc
> ics932s401
> isl29003
> diff --git a/Documentation/misc-devices/intel/gna.rst b/Documentation/misc-devices/intel/gna.rst
> new file mode 100644
> index 000000000000..9baeec5ceb5c
> --- /dev/null
> +++ b/Documentation/misc-devices/intel/gna.rst
> @@ -0,0 +1,48 @@
> +.. SPDX-License-Identifier: GPL-2.0-only
> +
> +=====================================================
> +Intel(R) Gaussian & Neural Accelerator (Intel(R) GNA)
> +=====================================================
> +
> +Acronyms
> +--------
> +GNA - Gaussian & Neural Accelerator
> +GMM - Gaussian Mixer Model
> +CNN - Convolutional Neural Network
> +RNN - Recurrent Neural Networks
> +DNN - Deep Neural Networks
> +
> +Introduction
> +------------
> +The Intel(R) GNA is an internal PCI fixed device available on several Intel platforms/SoCs.
> +Feature set depends on the Intel chipset SKU.
> +
> +Intel(R) GNA provides hardware accelerated computation for GMMs and Neural Networks.
> +It supports several layer types: affine, recurrent, and convolutional among others.
> +Hardware also provides helper layer types for copying and transposing matrices.
> +
> +Linux Driver
> +------------
> +The driver also registers a character device to expose file operations via dev node.
> +
> +The driver probes/removes PCI device, implements file operations, handles runtime
a PCI device
> +power management, and interacts with hardware through MMIO registers.
> +
> +Multiple processes can independently file many requests to the driver. These requests are
> +processed in a FIFO manner. The hardware can process one request at a time by using a FIFO
> +queue.
> +
> +IOCTL
> +-----
> +Intel(R) GNA driver controls the device through IOCTL interfaces.
> +Following IOCTL commands are supported:
> +
> +GNA_IOCTL_PARAM_GET gets driver and device capabilities.
> +
> +GNA_IOCTL_MEMORY_MAP locks user pages and GNA MMU setups for DMA transfer.
> +
> +GNA_IOCTL_MEMORY_UNMAP unlocks user pages and releases GNA MMU structures.
> +
> +GNA_IOCTL_COMPUTE submits a request to the device queue.
> +
> +GNA_IOCTL_WAIT blocks and waits on the submitted request.
> diff --git a/Documentation/userspace-api/ioctl/ioctl-number.rst b/Documentation/userspace-api/ioctl/ioctl-number.rst
> index a4c75a28c839..9ec2b32f656a 100644
> --- a/Documentation/userspace-api/ioctl/ioctl-number.rst
> +++ b/Documentation/userspace-api/ioctl/ioctl-number.rst
> @@ -115,6 +115,7 @@ Code Seq# Include File Comments
> 'B' C0-FF advanced bbus <mailto:maassen@xxxxxxxxxxxxxxx>
> 'C' all linux/soundcard.h conflict!
> 'C' 01-2F linux/capi.h conflict!
> +'C' 01-5F uapi/misc/intel/gna.h conflict!
> 'C' F0-FF drivers/net/wan/cosa.h conflict!
> 'D' all arch/s390/include/asm/dasd.h
> 'D' 40-5F drivers/scsi/dpt/dtpi_ioctl.h
> diff --git a/MAINTAINERS b/MAINTAINERS
> index bfc1b86e3e73..da926aa4523c 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -8928,6 +8928,13 @@ S: Maintained
> F: Documentation/fb/intelfb.rst
> F: drivers/video/fbdev/intelfb/
>
> +INTEL GNA PCI DRIVER
> +M: Maciej Kwapulinski <maciej.kwapulinski@xxxxxxxxxxxxxxx>
> +S: Maintained
> +F: Documentation/misc-devices/intel/gna.rst
> +F: drivers/misc/intel/gna/*
> +F: include/uapi/misc/intel/gna.h
> +
> INTEL GPIO DRIVERS
> M: Andy Shevchenko <andy@xxxxxxxxxx>
> L: linux-gpio@xxxxxxxxxxxxxxx
> diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
> index fafa8b0d8099..ce3dc5b9f821 100644
> --- a/drivers/misc/Kconfig
> +++ b/drivers/misc/Kconfig
> @@ -481,4 +481,5 @@ source "drivers/misc/ocxl/Kconfig"
> source "drivers/misc/cardreader/Kconfig"
> source "drivers/misc/habanalabs/Kconfig"
> source "drivers/misc/uacce/Kconfig"
> +source "drivers/misc/intel/gna/Kconfig"
> endmenu
> diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
> index d23231e73330..5fca2e730d96 100644
> --- a/drivers/misc/Makefile
> +++ b/drivers/misc/Makefile
> @@ -57,3 +57,4 @@ obj-$(CONFIG_HABANA_AI) += habanalabs/
> obj-$(CONFIG_UACCE) += uacce/
> obj-$(CONFIG_XILINX_SDFEC) += xilinx_sdfec.o
> obj-$(CONFIG_HISI_HIKEY_USB) += hisi_hikey_usb.o
> +obj-$(CONFIG_INTEL_GNA) += intel/gna/
> diff --git a/drivers/misc/intel/gna/Kbuild b/drivers/misc/intel/gna/Kbuild
> new file mode 100644
> index 000000000000..5d3becc71683
> --- /dev/null
> +++ b/drivers/misc/intel/gna/Kbuild
> @@ -0,0 +1,5 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +
> +intel_gna-y := gna_device.o gna_driver.o
> +
> +obj-$(CONFIG_INTEL_GNA) += intel_gna.o
> diff --git a/drivers/misc/intel/gna/Kconfig b/drivers/misc/intel/gna/Kconfig
> new file mode 100644
> index 000000000000..c3b768a40684
> --- /dev/null
> +++ b/drivers/misc/intel/gna/Kconfig
> @@ -0,0 +1,13 @@
> +#
> +# Intel(R) Gaussian & Neural Accelerator (Intel(R) GNA)
> +#
> +
> +config INTEL_GNA
> + tristate "Intel(R) Gaussian & Neural Accelerator (Intel(R) GNA)"
> + depends on X86_64 && PCI
Why 64?
> + help
> + This option enables the Intel(R) Gaussian & Neural Accelerator
> + (Intel(R) GNA) driver: intel_gna.
> + User space interface is defined in include/uapi/misc/intel/gna.h, while
> + information about functionality is in
> + Documentation/misc-devices/intel/gna.rst
> diff --git a/drivers/misc/intel/gna/gna_device.c b/drivers/misc/intel/gna/gna_device.c
> new file mode 100644
> index 000000000000..431113297879
> --- /dev/null
> +++ b/drivers/misc/intel/gna/gna_device.c
> @@ -0,0 +1,74 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +// Copyright(c) 2017-2021 Intel Corporation
> +
> +#include <linux/module.h>
> +#include <linux/pci.h>
> +
> +#include "gna_device.h"
> +#include "gna_driver.h"
> +#define GNA_BAR0 0
Why? Expecting something different?
> +static void gna_dev_init(struct gna_private *gna_priv, struct pci_dev *pcidev,
> + const struct pci_device_id *pci_id)
> +{
> + pci_set_drvdata(pcidev, gna_priv);
You assign this and make it visible before assigning fields. Not good.
> + gna_priv->parent = &pcidev->dev;
> + gna_priv->pdev = pcidev;
> + gna_priv->info = *(struct gna_drv_info *)pci_id->driver_data;
> + gna_priv->drv_priv = &gna_drv_priv;
> +}
Why is this can't be inlined into ->probe() ?
> +int gna_probe(struct pci_dev *pcidev, const struct pci_device_id *pci_id)
> +{
> + struct gna_private *gna_priv;
> + void __iomem *const *iomap;
> + unsigned long phys_len;
> + phys_addr_t phys;
> + int ret;
> +
> + ret = pcim_enable_device(pcidev);
> + if (ret) {
> + dev_err(&pcidev->dev, "pci device can't be enabled\n");
> + return ret;
> + }
> +
> + ret = pcim_iomap_regions(pcidev, 1 << GNA_BAR0, GNA_DV_NAME);
> + if (ret) {
> + dev_err(&pcidev->dev, "cannot iomap regions\n");
> + return ret;
> + }
> + phys = pci_resource_start(pcidev, GNA_BAR0);
> + phys_len = pci_resource_len(pcidev, GNA_BAR0);
> +
> + dev_info(&pcidev->dev, "physical base address %pap, %lu bytes\n",
> + &phys, phys_len);
Why is it important?
> + iomap = pcim_iomap_table(pcidev);
> + if (!iomap) {
> + dev_err(&pcidev->dev, "failed to iomap table\n");
> + return -ENODEV;
> + }
This conditional is redundant.
> + gna_priv = devm_kzalloc(&pcidev->dev, sizeof(*gna_priv), GFP_KERNEL);
> + if (!gna_priv)
> + return -ENOMEM;
> +
> + gna_priv->bar0_base = iomap[GNA_BAR0];
> +
> + dev_dbg(&pcidev->dev, "bar0 memory address: %p\n", gna_priv->bar0_base);
> +
> + ret = dma_set_mask(&pcidev->dev, DMA_BIT_MASK(64));
> + if (ret) {
> + dev_err(&pcidev->dev, "pci_set_dma_mask returned error %d\n", ret);
Typo in the message.
Why not try to fall back to 32 bit mask and support 32-bit builds?
> + return ret;
> + }
> +
> + pci_set_master(pcidev);
> +
> + gna_dev_init(gna_priv, pcidev, pci_id);
> +
> + return 0;
> +}
> diff --git a/drivers/misc/intel/gna/gna_device.h b/drivers/misc/intel/gna/gna_device.h
> new file mode 100644
> index 000000000000..d0b47f75f47f
> --- /dev/null
> +++ b/drivers/misc/intel/gna/gna_device.h
> @@ -0,0 +1,36 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/* Copyright(c) 2017-2021 Intel Corporation */
> +
> +#ifndef __GNA_DEVICE_H__
> +#define __GNA_DEVICE_H__
> +
> +#include <linux/types.h>
> +
> +struct gna_driver_private;
> +struct pci_device_id;
> +struct pci_dev;
> +struct device;
> +
> +struct gna_drv_info {
> + u32 hwid;
> + u32 num_pagetables;
> + u32 num_page_entries;
> + u32 max_layer_count;
> + u64 max_hw_mem;
> +};
> +
> +struct gna_private {
> + struct gna_driver_private *drv_priv;
> + struct pci_dev *pdev;
> + /* pdev->dev */
> + struct device *parent;
This is a mess. One struct device is enough.
Comment doesn't bring any value and is confusing.
> + /* device related resources */
> + void __iomem *bar0_base;
> + struct gna_drv_info info;
> +};
> +int gna_probe(struct pci_dev *dev, const struct pci_device_id *id);
This looks wrong. If you provide ->probe() function for others, it's
probably generalized enough and mustn't be PCI or any other bus
dependent. See below.
> +#endif /* __GNA_DEVICE_H__ */
> diff --git a/drivers/misc/intel/gna/gna_driver.c b/drivers/misc/intel/gna/gna_driver.c
> new file mode 100644
> index 000000000000..f4922a388be7
> --- /dev/null
> +++ b/drivers/misc/intel/gna/gna_driver.c
> @@ -0,0 +1,39 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +// Copyright(c) 2017-2021 Intel Corporation
> +
> +#include <linux/jiffies.h>
> +#include <linux/module.h>
> +#include <linux/pci.h>
> +
> +#include "gna_device.h"
> +#include "gna_driver.h"
> +
> +static int recovery_timeout = 60;
> +module_param(recovery_timeout, int, 0644);
> +MODULE_PARM_DESC(recovery_timeout, "Recovery timeout in seconds");
Why module parameters?!
> +struct gna_driver_private gna_drv_priv;
Global?!
> +static struct pci_driver gna_driver = {
> + .name = GNA_DV_NAME,
> + .probe = gna_probe,
> +};
> +
> +static int __init gna_drv_init(void)
> +{
> + gna_drv_priv.recovery_timeout_jiffies = msecs_to_jiffies(recovery_timeout * 1000);
> +
> + return pci_register_driver(&gna_driver);
> +}
> +
> +static void __exit gna_drv_exit(void)
> +{
> + pci_unregister_driver(&gna_driver);
> +}
> +
> +module_init(gna_drv_init);
> +module_exit(gna_drv_exit);
What is this entire module for?!
Really you should not split this like above. This belongs to the PCI
glue driver.
> +MODULE_AUTHOR("Intel Corporation");
> +MODULE_DESCRIPTION("Intel(R) Gaussian & Neural Accelerator (Intel(R) GNA) Driver");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/misc/intel/gna/gna_driver.h b/drivers/misc/intel/gna/gna_driver.h
> new file mode 100644
> index 000000000000..ed507ea10866
> --- /dev/null
> +++ b/drivers/misc/intel/gna/gna_driver.h
> @@ -0,0 +1,15 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/* Copyright(c) 2017-2021 Intel Corporation */
> +
> +#ifndef __GNA_DRIVER_H__
> +#define __GNA_DRIVER_H__
> +
> +#define GNA_DV_NAME "intel_gna"
> +
> +struct gna_driver_private {
> + int recovery_timeout_jiffies;
> +};
> +
> +extern struct gna_driver_private gna_drv_priv;
> +
> +#endif /* __GNA_DRIVER_H__ */
> diff --git a/include/uapi/misc/intel/gna.h b/include/uapi/misc/intel/gna.h
> new file mode 100644
> index 000000000000..a7e435b74a0a
> --- /dev/null
> +++ b/include/uapi/misc/intel/gna.h
> @@ -0,0 +1,155 @@
> +/* SPDX-License-Identifier: GPL-2.0-only WITH Linux-syscall-note */
> +/* Copyright(c) 2017-2021 Intel Corporation */
> +
> +#ifndef _UAPI_GNA_H_
> +#define _UAPI_GNA_H_
> +
> +#if defined(__cplusplus)
> +extern "C" {
> +#endif
> +#include <linux/types.h>
> +#include <linux/ioctl.h>
> +#include <linux/const.h>
Ordered?
> +#ifndef __user
> +#define __user
> +#endif
What for?
> +/* Operation modes */
> +#define GNA_MODE_GMM 0
> +#define GNA_MODE_XNN 1
> +
> +#define GNA_PARAM_DEVICE_ID 1
> +#define GNA_PARAM_RECOVERY_TIMEOUT 2
> +#define GNA_PARAM_DEVICE_TYPE 3
> +#define GNA_PARAM_INPUT_BUFFER_S 4
> +
> +#define GNA_STS_SCORE_COMPLETED _BITUL(0)
> +#define GNA_STS_STATISTICS_VALID _BITUL(3)
> +#define GNA_STS_PCI_MMU_ERR _BITUL(4)
> +#define GNA_STS_PCI_DMA_ERR _BITUL(5)
> +#define GNA_STS_PCI_UNEXCOMPL_ERR _BITUL(6)
> +#define GNA_STS_VA_OOR _BITUL(7)
> +#define GNA_STS_PARAM_OOR _BITUL(8)
> +#define GNA_STS_SATURATE _BITUL(17)
> +
> +#define GNA_ERROR (GNA_STS_PCI_DMA_ERR | \
Better to start value on the new line.
> + GNA_STS_PCI_MMU_ERR | \
> + GNA_STS_PCI_UNEXCOMPL_ERR | \
> + GNA_STS_PARAM_OOR | \
> + GNA_STS_VA_OOR)
> +
> +#define GNA_DEV_TYPE_0_9 0x09
> +#define GNA_DEV_TYPE_1_0 0x10
> +#define GNA_DEV_TYPE_2_0 0x20
> +
> +/*
> + * Structure describes part of memory to be overwritten before starting GNA
> + */
> +struct gna_memory_patch {
> + /* offset from targeted memory */
> + __u64 offset;
> +
> + __u64 size;
> + __u64 value;
> +};
> +
> +struct gna_buffer {
> + __u64 memory_id;
> +
> + __u64 offset;
> + __u64 size;
> +
> + __u64 patch_count;
> + __u64 patches_ptr;
> +};
> +
> +/*
> + * Driver performance timestamps in nanoseconds.
> + * Values regard system boot time, but do not count during suspend.
> + */
> +struct gna_drv_perf {
> + __u64 pre_processing; /* driver starts pre-processing */
> + __u64 processing; /* hw starts processing */
> + __u64 hw_completed; /* hw finishes processing */
> + __u64 completion; /* driver finishes post-processing */
> +};
> +
> +struct gna_hw_perf {
> + __u64 total;
> + __u64 stall;
> +};
> +
> +struct gna_compute_cfg {
> + __u32 layer_base;
> + __u32 layer_count;
> +
> + /* List of GNA memory buffers */
> + __u64 buffers_ptr;
> + __u64 buffer_count;
> +
> + __u8 active_list_on;
> + __u8 gna_mode;
> + __u8 hw_perf_encoding;
> + __u8 pad[5];
> +};
> +
> +union gna_parameter {
> + struct {
> + __u64 id;
> + } in;
> +
> + struct {
> + __u64 value;
> + } out;
> +};
> +
> +union gna_memory_map {
> + struct {
> + __u64 address;
> + __u32 size;
> + __u32 pad;
> + } in;
> +
> + struct {
> + __u64 memory_id;
> + } out;
> +};
> +
> +union gna_compute {
> + struct {
> + struct gna_compute_cfg config;
> + } in;
> +
> + struct {
> + __u64 request_id;
> + } out;
> +};
> +
> +union gna_wait {
> + struct {
> + __u64 request_id;
> + __u32 timeout;
> + __u32 pad;
> + } in;
> +
> + struct {
> + __u32 hw_status;
> + __u32 pad;
> + struct gna_drv_perf drv_perf;
> + struct gna_hw_perf hw_perf;
> + } out;
> +};
For all unions:
How do you know which branch is used (out, in)? What field and where
in the ABI points to that?
> +#define GNA_GET_PARAMETER _IOWR('C', 0x01, union gna_parameter)
> +#define GNA_MAP_MEMORY _IOWR('C', 0x02, union gna_memory_map)
> +#define GNA_UNMAP_MEMORY _IOWR('C', 0x03, __u64)
> +#define GNA_COMPUTE _IOWR('C', 0x04, union gna_compute)
> +#define GNA_WAIT _IOWR('C', 0x05, union gna_wait)
> +
> +#if defined(__cplusplus)
> +}
> +#endif
> +
> +#endif /* _UAPI_GNA_H_ */
> --
> 2.28.0
>
--
With Best Regards,
Andy Shevchenko