misc: bcm-vk: add Broadcom VK driver

Add initial version of Broadcom VK driver to enumerate PCI device IDs
of Valkyrie and Viper device IDs.

VK based cards provide real-time high performance, high throughput,
low latency offload compute engine operations.
They are used for multiple parallel offload tasks as:
audio, video and image processing and crypto operations.

Further commits add additional features to driver beyond probe/remove.

Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Scott Branden <scott.branden@broadcom.com>
Link: https://lore.kernel.org/r/20210120175827.14820-3-scott.branden@broadcom.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/Kconfig

@@ -470,6 +470,7 @@ source "drivers/misc/genwqe/Kconfig"
 source "drivers/misc/echo/Kconfig"
 source "drivers/misc/cxl/Kconfig"
 source "drivers/misc/ocxl/Kconfig"
+source "drivers/misc/bcm-vk/Kconfig"
 source "drivers/misc/cardreader/Kconfig"
 source "drivers/misc/habanalabs/Kconfig"
 source "drivers/misc/uacce/Kconfig"

drivers/misc/Makefile

@@ -50,6 +50,7 @@ obj-$(CONFIG_ECHO)		+= echo/
 obj-$(CONFIG_CXL_BASE)		+= cxl/
 obj-$(CONFIG_PCI_ENDPOINT_TEST)	+= pci_endpoint_test.o
 obj-$(CONFIG_OCXL)		+= ocxl/
+obj-$(CONFIG_BCM_VK)		+= bcm-vk/
 obj-y				+= cardreader/
 obj-$(CONFIG_PVPANIC)   	+= pvpanic.o
 obj-$(CONFIG_HABANA_AI)		+= habanalabs/

drivers/misc/bcm-vk/Kconfig

@@ -0,0 +1,17 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Broadcom VK device
+#
+config BCM_VK
+	tristate "Support for Broadcom VK Accelerators"
+	depends on PCI_MSI
+	help
+	  Select this option to enable support for Broadcom
+	  VK Accelerators.  VK is used for performing
+	  multiple specific offload processing tasks in parallel.
+	  Such offload tasks assist in such operations as video
+	  transcoding, compression, and crypto tasks.
+	  This driver enables userspace programs to access these
+	  accelerators via /dev/bcm-vk.N devices.
+
+	  If unsure, say N.

drivers/misc/bcm-vk/Makefile

@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for Broadcom VK driver
+#
+
+obj-$(CONFIG_BCM_VK) += bcm_vk.o
+bcm_vk-objs := \
+	bcm_vk_dev.o

drivers/misc/bcm-vk/bcm_vk.h

@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright 2018-2020 Broadcom.
+ */
+
+#ifndef BCM_VK_H
+#define BCM_VK_H
+
+#include <linux/pci.h>
+
+#define DRV_MODULE_NAME		"bcm-vk"
+
+/* VK device supports a maximum of 3 bars */
+#define MAX_BAR	3
+
+enum pci_barno {
+	BAR_0 = 0,
+	BAR_1,
+	BAR_2
+};
+
+#define BCM_VK_NUM_TTY 2
+
+struct bcm_vk {
+	struct pci_dev *pdev;
+	void __iomem *bar[MAX_BAR];
+};
+
+#endif

drivers/misc/bcm-vk/bcm_vk_dev.c

@@ -0,0 +1,141 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2018-2020 Broadcom.
+ */
+
+#include <linux/dma-mapping.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/pci_regs.h>
+
+#include "bcm_vk.h"
+
+#define PCI_DEVICE_ID_VALKYRIE	0x5e87
+#define PCI_DEVICE_ID_VIPER	0x5e88
+
+/* MSIX usages */
+#define VK_MSIX_MSGQ_MAX		3
+#define VK_MSIX_NOTF_MAX		1
+#define VK_MSIX_TTY_MAX			BCM_VK_NUM_TTY
+#define VK_MSIX_IRQ_MAX			(VK_MSIX_MSGQ_MAX + VK_MSIX_NOTF_MAX + \
+					 VK_MSIX_TTY_MAX)
+#define VK_MSIX_IRQ_MIN_REQ             (VK_MSIX_MSGQ_MAX + VK_MSIX_NOTF_MAX)
+
+/* Number of bits set in DMA mask*/
+#define BCM_VK_DMA_BITS			64
+
+static int bcm_vk_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
+{
+	int err;
+	int i;
+	int irq;
+	struct bcm_vk *vk;
+	struct device *dev = &pdev->dev;
+
+	vk = kzalloc(sizeof(*vk), GFP_KERNEL);
+	if (!vk)
+		return -ENOMEM;
+
+	err = pci_enable_device(pdev);
+	if (err) {
+		dev_err(dev, "Cannot enable PCI device\n");
+		goto err_free_exit;
+	}
+	vk->pdev = pci_dev_get(pdev);
+
+	err = pci_request_regions(pdev, DRV_MODULE_NAME);
+	if (err) {
+		dev_err(dev, "Cannot obtain PCI resources\n");
+		goto err_disable_pdev;
+	}
+
+	/* make sure DMA is good */
+	err = dma_set_mask_and_coherent(&pdev->dev,
+					DMA_BIT_MASK(BCM_VK_DMA_BITS));
+	if (err) {
+		dev_err(dev, "failed to set DMA mask\n");
+		goto err_disable_pdev;
+	}
+
+	pci_set_master(pdev);
+	pci_set_drvdata(pdev, vk);
+
+	irq = pci_alloc_irq_vectors(pdev,
+				    1,
+				    VK_MSIX_IRQ_MAX,
+				    PCI_IRQ_MSI | PCI_IRQ_MSIX);
+
+	if (irq < VK_MSIX_IRQ_MIN_REQ) {
+		dev_err(dev, "failed to get min %d MSIX interrupts, irq(%d)\n",
+			VK_MSIX_IRQ_MIN_REQ, irq);
+		err = (irq >= 0) ? -EINVAL : irq;
+		goto err_disable_pdev;
+	}
+
+	if (irq != VK_MSIX_IRQ_MAX)
+		dev_warn(dev, "Number of IRQs %d allocated - requested(%d).\n",
+			 irq, VK_MSIX_IRQ_MAX);
+
+	for (i = 0; i < MAX_BAR; i++) {
+		/* multiple by 2 for 64 bit BAR mapping */
+		vk->bar[i] = pci_ioremap_bar(pdev, i * 2);
+		if (!vk->bar[i]) {
+			dev_err(dev, "failed to remap BAR%d\n", i);
+			goto err_iounmap;
+		}
+	}
+
+	return 0;
+
+err_iounmap:
+	for (i = 0; i < MAX_BAR; i++) {
+		if (vk->bar[i])
+			pci_iounmap(pdev, vk->bar[i]);
+	}
+	pci_release_regions(pdev);
+
+err_disable_pdev:
+	pci_free_irq_vectors(pdev);
+	pci_disable_device(pdev);
+	pci_dev_put(pdev);
+
+err_free_exit:
+	kfree(vk);
+
+	return err;
+}
+
+static void bcm_vk_remove(struct pci_dev *pdev)
+{
+	int i;
+	struct bcm_vk *vk = pci_get_drvdata(pdev);
+
+	for (i = 0; i < MAX_BAR; i++) {
+		if (vk->bar[i])
+			pci_iounmap(pdev, vk->bar[i]);
+	}
+
+	pci_release_regions(pdev);
+	pci_free_irq_vectors(pdev);
+	pci_disable_device(pdev);
+}
+
+static const struct pci_device_id bcm_vk_ids[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_BROADCOM, PCI_DEVICE_ID_VALKYRIE), },
+	{ PCI_DEVICE(PCI_VENDOR_ID_BROADCOM, PCI_DEVICE_ID_VIPER), },
+	{ }
+};
+MODULE_DEVICE_TABLE(pci, bcm_vk_ids);
+
+static struct pci_driver pci_driver = {
+	.name     = DRV_MODULE_NAME,
+	.id_table = bcm_vk_ids,
+	.probe    = bcm_vk_probe,
+	.remove   = bcm_vk_remove,
+};
+module_pci_driver(pci_driver);
+
+MODULE_DESCRIPTION("Broadcom VK Host Driver");
+MODULE_AUTHOR("Scott Branden <scott.branden@broadcom.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_VERSION("1.0");