[PATCH char-misc-next v4 12/13] misc: mic: MIC card driver specific changes to enable SCIF

From: Sudeep Dutt
Date: Mon Mar 30 2015 - 21:38:13 EST

MIC card driver specific changes to enable SCIF. This patch implements
the SCIF hardware bus operations and registers a SCIF device on the
SCIF hardware bus.

Reviewed-by: Nikhil Rao <nikhil.rao@xxxxxxxxx>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@xxxxxxxxx>
Signed-off-by: Sudeep Dutt <sudeep.dutt@xxxxxxxxx>
---
drivers/misc/mic/Kconfig | 2 +-
drivers/misc/mic/card/mic_device.h | 11 +++-
drivers/misc/mic/card/mic_x100.h | 1 +
drivers/misc/mic/card/mic_device.c | 132 ++++++++++++++++++++++++++++++++++++-
drivers/misc/mic/card/mic_x100.c | 61 ++++++++++++++++-
5 files changed, 201 insertions(+), 6 deletions(-)

diff --git a/drivers/misc/mic/Kconfig b/drivers/misc/mic/Kconfig
index a2ea3ab..e9f2f56 100644
--- a/drivers/misc/mic/Kconfig
+++ b/drivers/misc/mic/Kconfig
@@ -56,7 +56,7 @@ comment "Intel MIC Card Driver"

config INTEL_MIC_CARD
tristate "Intel MIC Card Driver"
- depends on 64BIT && X86 && INTEL_MIC_BUS
+ depends on 64BIT && X86 && INTEL_MIC_BUS && SCIF_BUS
select VIRTIO
help
This enables card driver support for the Intel Many Integrated
diff --git a/drivers/misc/mic/card/mic_device.h b/drivers/misc/mic/card/mic_device.h
index 844be8f..1dbf83c 100644
--- a/drivers/misc/mic/card/mic_device.h
+++ b/drivers/misc/mic/card/mic_device.h
@@ -29,9 +29,9 @@

#include <linux/workqueue.h>
#include <linux/io.h>
-#include <linux/irqreturn.h>
#include <linux/interrupt.h>
#include <linux/mic_bus.h>
+#include "../bus/scif_bus.h"

/**
* struct mic_intr_info - Contains h/w specific interrupt sources info
@@ -73,6 +73,9 @@ struct mic_device {
* @irq_info: The OS specific irq information
* @intr_info: H/W specific interrupt information.
* @dma_mbdev: dma device on the MIC virtual bus.
+ * @dma_ch - Array of DMA channels
+ * @num_dma_ch - Number of DMA channels available
+ * @scdev: SCIF device on the SCIF virtual bus.
*/
struct mic_driver {
char name[20];
@@ -84,6 +87,9 @@ struct mic_driver {
struct mic_irq_info irq_info;
struct mic_intr_info intr_info;
struct mbus_device *dma_mbdev;
+ struct dma_chan *dma_ch[MIC_MAX_DMA_CHAN];
+ int num_dma_ch;
+ struct scif_hw_dev *scdev;
};

/**
@@ -122,10 +128,11 @@ void mic_driver_uninit(struct mic_driver *mdrv);
int mic_next_card_db(void);
struct mic_irq *
mic_request_card_irq(irq_handler_t handler, irq_handler_t thread_fn,
- const char *name, void *data, int intr_src);
+ const char *name, void *data, int db);
void mic_free_card_irq(struct mic_irq *cookie, void *data);
u32 mic_read_spad(struct mic_device *mdev, unsigned int idx);
void mic_send_intr(struct mic_device *mdev, int doorbell);
+void mic_send_p2p_intr(int doorbell, struct mic_mw *mw);
int mic_db_to_irq(struct mic_driver *mdrv, int db);
u32 mic_ack_interrupt(struct mic_device *mdev);
void mic_hw_intr_init(struct mic_driver *mdrv);
diff --git a/drivers/misc/mic/card/mic_x100.h b/drivers/misc/mic/card/mic_x100.h
index d66ea55..7e22249 100644
--- a/drivers/misc/mic/card/mic_x100.h
+++ b/drivers/misc/mic/card/mic_x100.h
@@ -35,6 +35,7 @@
#define MIC_X100_SBOX_SDBIC0 0x0000CC90
#define MIC_X100_SBOX_SDBIC0_DBREQ_BIT 0x80000000
#define MIC_X100_SBOX_RDMASR0 0x0000B180
+#define MIC_X100_SBOX_APICICR0 0x0000A9D0

#define MIC_X100_MAX_DOORBELL_IDX 8

diff --git a/drivers/misc/mic/card/mic_device.c b/drivers/misc/mic/card/mic_device.c
index 83819ee..6338908 100644
--- a/drivers/misc/mic/card/mic_device.c
+++ b/drivers/misc/mic/card/mic_device.c
@@ -28,6 +28,8 @@
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/reboot.h>
+#include <linux/dmaengine.h>
+#include <linux/kmod.h>

#include <linux/mic_common.h>
#include "../common/mic_dev.h"
@@ -240,6 +242,111 @@ static void mic_uninit_irq(void)
kfree(mdrv->irq_info.irq_usage_count);
}

+static inline struct mic_driver *scdev_to_mdrv(struct scif_hw_dev *scdev)
+{
+ return dev_get_drvdata(scdev->dev.parent);
+}
+
+static struct mic_irq *
+___mic_request_irq(struct scif_hw_dev *scdev,
+ irqreturn_t (*func)(int irq, void *data),
+ const char *name, void *data,
+ int db)
+{
+ return mic_request_card_irq(func, NULL, name, data, db);
+}
+
+static void
+___mic_free_irq(struct scif_hw_dev *scdev,
+ struct mic_irq *cookie, void *data)
+{
+ return mic_free_card_irq(cookie, data);
+}
+
+static void ___mic_ack_interrupt(struct scif_hw_dev *scdev, int num)
+{
+ struct mic_driver *mdrv = scdev_to_mdrv(scdev);
+
+ mic_ack_interrupt(&mdrv->mdev);
+}
+
+static int ___mic_next_db(struct scif_hw_dev *scdev)
+{
+ return mic_next_card_db();
+}
+
+static void ___mic_send_intr(struct scif_hw_dev *scdev, int db)
+{
+ struct mic_driver *mdrv = scdev_to_mdrv(scdev);
+
+ mic_send_intr(&mdrv->mdev, db);
+}
+
+static void ___mic_send_p2p_intr(struct scif_hw_dev *scdev, int db,
+ struct mic_mw *mw)
+{
+ mic_send_p2p_intr(db, mw);
+}
+
+static void __iomem *
+___mic_ioremap(struct scif_hw_dev *scdev,
+ phys_addr_t pa, size_t len)
+{
+ struct mic_driver *mdrv = scdev_to_mdrv(scdev);
+
+ return mic_card_map(&mdrv->mdev, pa, len);
+}
+
+static void ___mic_iounmap(struct scif_hw_dev *scdev, void __iomem *va)
+{
+ struct mic_driver *mdrv = scdev_to_mdrv(scdev);
+
+ mic_card_unmap(&mdrv->mdev, va);
+}
+
+static struct scif_hw_ops scif_hw_ops = {
+ .request_irq = ___mic_request_irq,
+ .free_irq = ___mic_free_irq,
+ .ack_interrupt = ___mic_ack_interrupt,
+ .next_db = ___mic_next_db,
+ .send_intr = ___mic_send_intr,
+ .send_p2p_intr = ___mic_send_p2p_intr,
+ .ioremap = ___mic_ioremap,
+ .iounmap = ___mic_iounmap,
+};
+
+static int mic_request_dma_chans(struct mic_driver *mdrv)
+{
+ dma_cap_mask_t mask;
+ struct dma_chan *chan;
+
+ request_module("mic_x100_dma");
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_MEMCPY, mask);
+
+ do {
+ chan = dma_request_channel(mask, NULL, NULL);
+ if (chan) {
+ mdrv->dma_ch[mdrv->num_dma_ch++] = chan;
+ if (mdrv->num_dma_ch >= MIC_MAX_DMA_CHAN)
+ break;
+ }
+ } while (chan);
+ dev_info(mdrv->dev, "DMA channels # %d\n", mdrv->num_dma_ch);
+ return mdrv->num_dma_ch;
+}
+
+static void mic_free_dma_chans(struct mic_driver *mdrv)
+{
+ int i = 0;
+
+ for (i = 0; i < mdrv->num_dma_ch; i++) {
+ dma_release_channel(mdrv->dma_ch[i]);
+ mdrv->dma_ch[i] = NULL;
+ }
+ mdrv->num_dma_ch = 0;
+}
+
/*
* mic_driver_init - MIC driver initialization tasks.
*
@@ -248,6 +355,8 @@ static void mic_uninit_irq(void)
int __init mic_driver_init(struct mic_driver *mdrv)
{
int rc;
+ struct mic_bootparam __iomem *bootparam;
+ u8 node_id;

g_drv = mdrv;
/*
@@ -268,13 +377,32 @@ int __init mic_driver_init(struct mic_driver *mdrv)
rc = mic_shutdown_init();
if (rc)
goto irq_uninit;
+ if (!mic_request_dma_chans(mdrv)) {
+ rc = -ENODEV;
+ goto shutdown_uninit;
+ }
rc = mic_devices_init(mdrv);
if (rc)
- goto shutdown_uninit;
+ goto dma_free;
+ bootparam = mdrv->dp;
+ node_id = ioread8(&bootparam->node_id);
+ mdrv->scdev = scif_register_device(mdrv->dev, MIC_SCIF_DEV,
+ NULL, &scif_hw_ops,
+ 0, node_id, &mdrv->mdev.mmio, NULL,
+ NULL, mdrv->dp, mdrv->dma_ch,
+ mdrv->num_dma_ch);
+ if (IS_ERR(mdrv->scdev)) {
+ rc = PTR_ERR(mdrv->scdev);
+ goto device_uninit;
+ }
mic_create_card_debug_dir(mdrv);
atomic_notifier_chain_register(&panic_notifier_list, &mic_panic);
done:
return rc;
+device_uninit:
+ mic_devices_uninit(mdrv);
+dma_free:
+ mic_free_dma_chans(mdrv);
shutdown_uninit:
mic_shutdown_uninit();
irq_uninit:
@@ -294,7 +422,9 @@ put:
void mic_driver_uninit(struct mic_driver *mdrv)
{
mic_delete_card_debug_dir(mdrv);
+ scif_unregister_device(mdrv->scdev);
mic_devices_uninit(mdrv);
+ mic_free_dma_chans(mdrv);
/*
* Inform the host about the shutdown status i.e. poweroff/restart etc.
* The module cannot be unloaded so the only code path to call
diff --git a/drivers/misc/mic/card/mic_x100.c b/drivers/misc/mic/card/mic_x100.c
index e98e537..77fd41781 100644
--- a/drivers/misc/mic/card/mic_x100.c
+++ b/drivers/misc/mic/card/mic_x100.c
@@ -70,6 +70,41 @@ void mic_send_intr(struct mic_device *mdev, int doorbell)
(MIC_X100_SBOX_SDBIC0 + (4 * doorbell)));
}

+/*
+ * mic_x100_send_sbox_intr - Send an MIC_X100_SBOX interrupt to MIC.
+ */
+static void mic_x100_send_sbox_intr(struct mic_mw *mw, int doorbell)
+{
+ u64 apic_icr_offset = MIC_X100_SBOX_APICICR0 + doorbell * 8;
+ u32 apicicr_low = mic_mmio_read(mw, MIC_X100_SBOX_BASE_ADDRESS +
+ apic_icr_offset);
+
+ /* for MIC we need to make sure we "hit" the send_icr bit (13) */
+ apicicr_low = (apicicr_low | (1 << 13));
+ /*
+ * Ensure that the interrupt is ordered w.r.t. previous stores
+ * to main memory. Fence instructions are not implemented in X100
+ * since execution is in order but a compiler barrier is still
+ * required.
+ */
+ wmb();
+ mic_mmio_write(mw, apicicr_low,
+ MIC_X100_SBOX_BASE_ADDRESS + apic_icr_offset);
+}
+
+static void mic_x100_send_rdmasr_intr(struct mic_mw *mw, int doorbell)
+{
+ int rdmasr_offset = MIC_X100_SBOX_RDMASR0 + (doorbell << 2);
+ /*
+ * Ensure that the interrupt is ordered w.r.t. previous stores
+ * to main memory. Fence instructions are not implemented in X100
+ * since execution is in order but a compiler barrier is still
+ * required.
+ */
+ wmb();
+ mic_mmio_write(mw, 0, MIC_X100_SBOX_BASE_ADDRESS + rdmasr_offset);
+}
+
/**
* mic_ack_interrupt - Device specific interrupt handling.
* @mdev: pointer to mic_device instance
@@ -91,6 +126,18 @@ static inline int mic_get_rdmasr_irq(int index)
return MIC_X100_RDMASR_IRQ_BASE + index;
}

+void mic_send_p2p_intr(int db, struct mic_mw *mw)
+{
+ int rdmasr_index;
+
+ if (db < MIC_X100_NUM_SBOX_IRQ) {
+ mic_x100_send_sbox_intr(mw, db);
+ } else {
+ rdmasr_index = db - MIC_X100_NUM_SBOX_IRQ;
+ mic_x100_send_rdmasr_intr(mw, rdmasr_index);
+ }
+}
+
/**
* mic_hw_intr_init - Initialize h/w specific interrupt
* information.
@@ -113,11 +160,15 @@ void mic_hw_intr_init(struct mic_driver *mdrv)
int mic_db_to_irq(struct mic_driver *mdrv, int db)
{
int rdmasr_index;
+
+ /*
+ * The total number of doorbell interrupts on the card are 16. Indices
+ * 0-8 falls in the SBOX category and 8-15 fall in the RDMASR category.
+ */
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;
+ rdmasr_index = db - MIC_X100_NUM_SBOX_IRQ;
return mic_get_rdmasr_irq(rdmasr_index);
}
}
@@ -243,10 +294,16 @@ static void mic_platform_shutdown(struct platform_device *pdev)
mic_remove(pdev);
}

+static u64 mic_dma_mask = DMA_BIT_MASK(64);
+
static struct platform_device mic_platform_dev = {
.name = mic_driver_name,
.id = 0,
.num_resources = 0,
+ .dev = {
+ .dma_mask = &mic_dma_mask,
+ .coherent_dma_mask = DMA_BIT_MASK(64),
+ },
};

static struct platform_driver __refdata mic_platform_driver = {
--
1.8.2.1

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