Intel MIC Card Driver for X100 family.

This patch does the following:
a) Initializes the Intel MIC X100 platform device and driver.
b) Sets up support to handle shutdown requests from the host.
c) Maps the device page after obtaining the device page address
from the scratchpad registers updated by the host.
d) Informs the host upon a card crash by registering a panic notifier.
e) Informs the host upon a poweroff/halt event.

Co-author: Dasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Caz Yokoyama <Caz.Yokoyama@intel.com>
Signed-off-by: Dasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: Nikhil Rao <nikhil.rao@intel.com>
Signed-off-by: Harshavardhan R Kharche <harshavardhan.r.kharche@intel.com>
Signed-off-by: Sudeep Dutt <sudeep.dutt@intel.com>
Acked-by: Yaozu (Eddie) Dong <eddie.dong@intel.com>
Reviewed-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 256 insertions, 0 deletions

diff --git a/drivers/misc/mic/card/mic_x100.c b/drivers/misc/mic/card/mic_x100.c
new file mode 100644
index 000000000000..7cb3469cf684
--- /dev/null
+++ b/drivers/misc/mic/card/mic_x100.c
@@ -0,0 +1,256 @@
+/*
+ * Intel MIC Platform Software Stack (MPSS)
+ *
+ * Copyright(c) 2013 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * The full GNU General Public License is included in this distribution in
+ * the file called "COPYING".
+ *
+ * Disclaimer: The codes contained in these modules may be specific to
+ * the Intel Software Development Platform codenamed: Knights Ferry, and
+ * the Intel product codenamed: Knights Corner, and are not backward
+ * compatible with other Intel products. Additionally, Intel will NOT
+ * support the codes or instruction set in future products.
+ *
+ * Intel MIC Card driver.
+ *
+ */
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+
+#include "../common/mic_device.h"
+#include "mic_device.h"
+#include "mic_x100.h"
+
+static const char mic_driver_name[] = "mic";
+
+static struct mic_driver g_drv;
+
+/**
+ * mic_read_spad - read from the scratchpad register
+ * @mdev: pointer to mic_device instance
+ * @idx: index to scratchpad register, 0 based
+ *
+ * This function allows reading of the 32bit scratchpad register.
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+u32 mic_read_spad(struct mic_device *mdev, unsigned int idx)
+{
+	return mic_mmio_read(&mdev->mmio,
+		MIC_X100_SBOX_BASE_ADDRESS +
+		MIC_X100_SBOX_SPAD0 + idx * 4);
+}
+
+/**
+ * __mic_send_intr - Send interrupt to Host.
+ * @mdev: pointer to mic_device instance
+ * @doorbell: Doorbell number.
+ */
+void mic_send_intr(struct mic_device *mdev, int doorbell)
+{
+	struct mic_mw *mw = &mdev->mmio;
+
+	if (doorbell > MIC_X100_MAX_DOORBELL_IDX)
+		return;
+	/* Ensure that the interrupt is ordered w.r.t previous stores. */
+	wmb();
+	mic_mmio_write(mw, MIC_X100_SBOX_SDBIC0_DBREQ_BIT,
+		MIC_X100_SBOX_BASE_ADDRESS +
+		(MIC_X100_SBOX_SDBIC0 + (4 * doorbell)));
+}
+
+/**
+ * mic_ack_interrupt - Device specific interrupt handling.
+ * @mdev: pointer to mic_device instance
+ *
+ * Returns: bitmask of doorbell events triggered.
+ */
+u32 mic_ack_interrupt(struct mic_device *mdev)
+{
+	return 0;
+}
+
+static inline int mic_get_sbox_irq(int db)
+{
+	return MIC_X100_IRQ_BASE + db;
+}
+
+static inline int mic_get_rdmasr_irq(int index)
+{
+	return  MIC_X100_RDMASR_IRQ_BASE + index;
+}
+
+/**
+ * mic_hw_intr_init - Initialize h/w specific interrupt
+ * information.
+ * @mdrv: pointer to mic_driver
+ */
+void mic_hw_intr_init(struct mic_driver *mdrv)
+{
+	mdrv->intr_info.num_intr = MIC_X100_NUM_SBOX_IRQ +
+				MIC_X100_NUM_RDMASR_IRQ;
+}
+
+/**
+ * mic_db_to_irq - Retrieve irq number corresponding to a doorbell.
+ * @mdrv: pointer to mic_driver
+ * @db: The doorbell obtained for which the irq is needed. Doorbell
+ * may correspond to an sbox doorbell or an rdmasr index.
+ *
+ * Returns the irq corresponding to the doorbell.
+ */
+int mic_db_to_irq(struct mic_driver *mdrv, int db)
+{
+	int rdmasr_index;
+	if (db < MIC_X100_NUM_SBOX_IRQ) {
+		return mic_get_sbox_irq(db);
+	} else {
+		rdmasr_index = db - MIC_X100_NUM_SBOX_IRQ +
+			MIC_X100_RDMASR_IRQ_BASE;
+		return mic_get_rdmasr_irq(rdmasr_index);
+	}
+}
+
+/*
+ * mic_card_map - Allocate virtual address for a remote memory region.
+ * @mdev: pointer to mic_device instance.
+ * @addr: Remote DMA address.
+ * @size: Size of the region.
+ *
+ * Returns: Virtual address backing the remote memory region.
+ */
+void __iomem *
+mic_card_map(struct mic_device *mdev, dma_addr_t addr, size_t size)
+{
+	return ioremap(addr, size);
+}
+
+/*
+ * mic_card_unmap - Unmap the virtual address for a remote memory region.
+ * @mdev: pointer to mic_device instance.
+ * @addr: Virtual address for remote memory region.
+ *
+ * Returns: None.
+ */
+void mic_card_unmap(struct mic_device *mdev, void __iomem *addr)
+{
+	iounmap(addr);
+}
+
+static int __init mic_probe(struct platform_device *pdev)
+{
+	struct mic_driver *mdrv = &g_drv;
+	struct mic_device *mdev = &mdrv->mdev;
+	int rc = 0;
+
+	mdrv->dev = &pdev->dev;
+	snprintf(mdrv->name, sizeof(mic_driver_name), mic_driver_name);
+
+	mdev->mmio.pa = MIC_X100_MMIO_BASE;
+	mdev->mmio.len = MIC_X100_MMIO_LEN;
+	mdev->mmio.va = ioremap(MIC_X100_MMIO_BASE, MIC_X100_MMIO_LEN);
+	if (!mdev->mmio.va) {
+		dev_err(&pdev->dev, "Cannot remap MMIO BAR\n");
+		rc = -EIO;
+		goto done;
+	}
+	mic_hw_intr_init(mdrv);
+	rc = mic_driver_init(mdrv);
+	if (rc) {
+		dev_err(&pdev->dev, "mic_driver_init failed rc %d\n", rc);
+		goto iounmap;
+	}
+done:
+	return rc;
+iounmap:
+	iounmap(mdev->mmio.va);
+	return rc;
+}
+
+static int mic_remove(struct platform_device *pdev)
+{
+	struct mic_driver *mdrv = &g_drv;
+	struct mic_device *mdev = &mdrv->mdev;
+
+	mic_driver_uninit(mdrv);
+	iounmap(mdev->mmio.va);
+	return 0;
+}
+
+static void mic_platform_shutdown(struct platform_device *pdev)
+{
+	mic_remove(pdev);
+}
+
+static struct platform_device mic_platform_dev = {
+	.name = mic_driver_name,
+	.id   = 0,
+	.num_resources = 0,
+};
+
+static struct platform_driver __refdata mic_platform_driver = {
+	.probe = mic_probe,
+	.remove = mic_remove,
+	.shutdown = mic_platform_shutdown,
+	.driver         = {
+		.name   = mic_driver_name,
+		.owner	= THIS_MODULE,
+	},
+};
+
+static int __init mic_init(void)
+{
+	int ret;
+	struct cpuinfo_x86 *c = &cpu_data(0);
+
+	if (!(c->x86 == 11 && c->x86_model == 1)) {
+		ret = -ENODEV;
+		pr_err("%s not running on X100 ret %d\n", __func__, ret);
+		goto done;
+	}
+
+	mic_init_card_debugfs();
+	ret = platform_device_register(&mic_platform_dev);
+	if (ret) {
+		pr_err("platform_device_register ret %d\n", ret);
+		goto cleanup_debugfs;
+	}
+	ret = platform_driver_register(&mic_platform_driver);
+	if (ret) {
+		pr_err("platform_driver_register ret %d\n", ret);
+		goto device_unregister;
+	}
+	return ret;
+
+device_unregister:
+	platform_device_unregister(&mic_platform_dev);
+cleanup_debugfs:
+	mic_exit_card_debugfs();
+done:
+	return ret;
+}
+
+static void __exit mic_exit(void)
+{
+	platform_driver_unregister(&mic_platform_driver);
+	platform_device_unregister(&mic_platform_dev);
+	mic_exit_card_debugfs();
+}
+
+module_init(mic_init);
+module_exit(mic_exit);
+
+MODULE_AUTHOR("Intel Corporation");
+MODULE_DESCRIPTION("Intel(R) MIC X100 Card driver");
+MODULE_LICENSE("GPL v2");