Intel MIC Host Driver, card OS state management.

This patch enables the following features:
a) Boots and shuts down the card via sysfs entries.
b) Allocates and maps a device page for communication with the
   card driver and updates the device page address via scratchpad
   registers.
c) Provides sysfs entries for shutdown status, kernel command line,
   ramdisk and log buffer information.

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: Harshavardhan R Kharche <harshavardhan.r.kharche@intel.com>
Signed-off-by: Nikhil Rao <nikhil.rao@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, 251 insertions, 0 deletions

diff --git a/drivers/misc/mic/host/mic_x100.c b/drivers/misc/mic/host/mic_x100.c
index b63731691c73..a12ae5c8844d 100644
--- a/drivers/misc/mic/host/mic_x100.c
+++ b/drivers/misc/mic/host/mic_x100.c
@@ -20,6 +20,9 @@
  */
 #include <linux/fs.h>
 #include <linux/pci.h>
+#include <linux/sched.h>
+#include <linux/firmware.h>
+#include <linux/delay.h>
 
 #include "../common/mic_device.h"
 #include "mic_device.h"
@@ -256,6 +259,248 @@ mic_x100_program_msi_to_src_map(struct mic_device *mdev,
         mic_mmio_write(mw, reg, mxar);
 }
 
+/*
+ * mic_x100_reset_fw_ready - Reset Firmware ready status field.
+ * @mdev: pointer to mic_device instance
+ */
+static void mic_x100_reset_fw_ready(struct mic_device *mdev)
+{
+        mdev->ops->write_spad(mdev, MIC_X100_DOWNLOAD_INFO, 0);
+}
+
+/*
+ * mic_x100_is_fw_ready - Check if firmware is ready.
+ * @mdev: pointer to mic_device instance
+ */
+static bool mic_x100_is_fw_ready(struct mic_device *mdev)
+{
+        u32 scratch2 = mdev->ops->read_spad(mdev, MIC_X100_DOWNLOAD_INFO);
+        return MIC_X100_SPAD2_DOWNLOAD_STATUS(scratch2) ? true : false;
+}
+
+/**
+ * mic_x100_get_apic_id - Get bootstrap APIC ID.
+ * @mdev: pointer to mic_device instance
+ */
+static u32 mic_x100_get_apic_id(struct mic_device *mdev)
+{
+        u32 scratch2 = 0;
+
+        scratch2 = mdev->ops->read_spad(mdev, MIC_X100_DOWNLOAD_INFO);
+        return MIC_X100_SPAD2_APIC_ID(scratch2);
+}
+
+/**
+ * mic_x100_send_firmware_intr - Send an interrupt to the firmware on MIC.
+ * @mdev: pointer to mic_device instance
+ */
+static void mic_x100_send_firmware_intr(struct mic_device *mdev)
+{
+        u32 apicicr_low;
+        u64 apic_icr_offset = MIC_X100_SBOX_APICICR7;
+        int vector = MIC_X100_BSP_INTERRUPT_VECTOR;
+        struct mic_mw *mw = &mdev->mmio;
+
+        /*
+         * For MIC we need to make sure we "hit"
+         * the send_icr bit (13).
+         */
+        apicicr_low = (vector | (1 << 13));
+
+        mic_mmio_write(mw, mic_x100_get_apic_id(mdev),
+                MIC_X100_SBOX_BASE_ADDRESS + apic_icr_offset + 4);
+
+        /* Ensure that the interrupt is ordered w.r.t. previous stores. */
+        wmb();
+        mic_mmio_write(mw, apicicr_low,
+                MIC_X100_SBOX_BASE_ADDRESS + apic_icr_offset);
+}
+
+/**
+ * mic_x100_hw_reset - Reset the MIC device.
+ * @mdev: pointer to mic_device instance
+ */
+static void mic_x100_hw_reset(struct mic_device *mdev)
+{
+        u32 reset_reg;
+        u32 rgcr = MIC_X100_SBOX_BASE_ADDRESS + MIC_X100_SBOX_RGCR;
+        struct mic_mw *mw = &mdev->mmio;
+
+        /* Ensure that the reset is ordered w.r.t. previous loads and stores */
+        mb();
+        /* Trigger reset */
+        reset_reg = mic_mmio_read(mw, rgcr);
+        reset_reg |= 0x1;
+        mic_mmio_write(mw, reset_reg, rgcr);
+        /*
+         * It seems we really want to delay at least 1 second
+         * after touching reset to prevent a lot of problems.
+         */
+        msleep(1000);
+}
+
+/**
+ * mic_x100_load_command_line - Load command line to MIC.
+ * @mdev: pointer to mic_device instance
+ * @fw: the firmware image
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+static int
+mic_x100_load_command_line(struct mic_device *mdev, const struct firmware *fw)
+{
+        u32 len = 0;
+        u32 boot_mem;
+        char *buf;
+        void __iomem *cmd_line_va = mdev->aper.va + mdev->bootaddr + fw->size;
+#define CMDLINE_SIZE 2048
+
+        boot_mem = mdev->aper.len >> 20;
+        buf = kzalloc(CMDLINE_SIZE, GFP_KERNEL);
+        if (!buf) {
+                dev_err(mdev->sdev->parent,
+                        "%s %d allocation failed\n", __func__, __LINE__);
+                return -ENOMEM;
+        }
+        len += snprintf(buf, CMDLINE_SIZE - len,
+                " mem=%dM", boot_mem);
+        if (mdev->cmdline)
+                snprintf(buf + len, CMDLINE_SIZE - len,
+                                " %s", mdev->cmdline);
+        memcpy_toio(cmd_line_va, buf, strlen(buf) + 1);
+        kfree(buf);
+        return 0;
+}
+
+/**
+ * mic_x100_load_ramdisk - Load ramdisk to MIC.
+ * @mdev: pointer to mic_device instance
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+static int
+mic_x100_load_ramdisk(struct mic_device *mdev)
+{
+        const struct firmware *fw;
+        int rc;
+        struct boot_params __iomem *bp = mdev->aper.va + mdev->bootaddr;
+
+        rc = request_firmware(&fw,
+                        mdev->ramdisk, mdev->sdev->parent);
+        if (rc < 0) {
+                dev_err(mdev->sdev->parent,
+                        "ramdisk request_firmware failed: %d %s\n",
+                        rc, mdev->ramdisk);
+                goto error;
+        }
+        /*
+         * Typically the bootaddr for card OS is 64M
+         * so copy over the ramdisk @ 128M.
+         */
+        memcpy_toio(mdev->aper.va + (mdev->bootaddr << 1),
+                fw->data, fw->size);
+        iowrite32(cpu_to_le32(mdev->bootaddr << 1), &bp->hdr.ramdisk_image);
+        iowrite32(cpu_to_le32(fw->size), &bp->hdr.ramdisk_size);
+        release_firmware(fw);
+error:
+        return rc;
+}
+
+/**
+ * mic_x100_get_boot_addr - Get MIC boot address.
+ * @mdev: pointer to mic_device instance
+ *
+ * This function is called during firmware load to determine
+ * the address at which the OS should be downloaded in card
+ * memory i.e. GDDR.
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+static int
+mic_x100_get_boot_addr(struct mic_device *mdev)
+{
+        u32 scratch2, boot_addr;
+        int rc = 0;
+
+        scratch2 = mdev->ops->read_spad(mdev, MIC_X100_DOWNLOAD_INFO);
+        boot_addr = MIC_X100_SPAD2_DOWNLOAD_ADDR(scratch2);
+        dev_dbg(mdev->sdev->parent, "%s %d boot_addr 0x%x\n",
+                __func__, __LINE__, boot_addr);
+        if (boot_addr > (1 << 31)) {
+                dev_err(mdev->sdev->parent,
+                        "incorrect bootaddr 0x%x\n",
+                        boot_addr);
+                rc = -EINVAL;
+                goto error;
+        }
+        mdev->bootaddr = boot_addr;
+error:
+        return rc;
+}
+
+/**
+ * mic_x100_load_firmware - Load firmware to MIC.
+ * @mdev: pointer to mic_device instance
+ * @buf: buffer containing boot string including firmware/ramdisk path.
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+static int
+mic_x100_load_firmware(struct mic_device *mdev, const char *buf)
+{
+        int rc;
+        const struct firmware *fw;
+
+        rc = mic_x100_get_boot_addr(mdev);
+        if (rc)
+                goto error;
+        /* load OS */
+        rc = request_firmware(&fw, mdev->firmware, mdev->sdev->parent);
+        if (rc < 0) {
+                dev_err(mdev->sdev->parent,
+                        "ramdisk request_firmware failed: %d %s\n",
+                        rc, mdev->firmware);
+                goto error;
+        }
+        if (mdev->bootaddr > mdev->aper.len - fw->size) {
+                rc = -EINVAL;
+                dev_err(mdev->sdev->parent, "%s %d rc %d bootaddr 0x%x\n",
+                        __func__, __LINE__, rc, mdev->bootaddr);
+                release_firmware(fw);
+                goto error;
+        }
+        memcpy_toio(mdev->aper.va + mdev->bootaddr, fw->data, fw->size);
+        mdev->ops->write_spad(mdev, MIC_X100_FW_SIZE, fw->size);
+        if (!strcmp(mdev->bootmode, "elf"))
+                goto done;
+        /* load command line */
+        rc = mic_x100_load_command_line(mdev, fw);
+        if (rc) {
+                dev_err(mdev->sdev->parent, "%s %d rc %d\n",
+                        __func__, __LINE__, rc);
+                goto error;
+        }
+        release_firmware(fw);
+        /* load ramdisk */
+        if (mdev->ramdisk)
+                rc = mic_x100_load_ramdisk(mdev);
+error:
+        dev_dbg(mdev->sdev->parent, "%s %d rc %d\n",
+                        __func__, __LINE__, rc);
+done:
+        return rc;
+}
+
+/**
+ * mic_x100_get_postcode - Get postcode status from firmware.
+ * @mdev: pointer to mic_device instance
+ *
+ * RETURNS: postcode.
+ */
+static u32 mic_x100_get_postcode(struct mic_device *mdev)
+{
+        return mic_mmio_read(&mdev->mmio, MIC_X100_POSTCODE);
+}
+
 /**
  * mic_x100_smpt_set - Update an SMPT entry with a DMA address.
  * @mdev: pointer to mic_device instance
@@ -311,6 +556,12 @@ struct mic_hw_ops mic_x100_ops = {
         .write_spad = mic_x100_write_spad,
         .send_intr = mic_x100_send_intr,
         .ack_interrupt = mic_x100_ack_interrupt,
+        .reset = mic_x100_hw_reset,
+        .reset_fw_ready = mic_x100_reset_fw_ready,
+        .is_fw_ready = mic_x100_is_fw_ready,
+        .send_firmware_intr = mic_x100_send_firmware_intr,
+        .load_mic_fw = mic_x100_load_firmware,
+        .get_postcode = mic_x100_get_postcode,
 };
 
 struct mic_hw_intr_ops mic_x100_intr_ops = {