[PATCH 0/2] rapidio: add inbound memory mapping API

[PATCH 0/2] rapidio: add inbound memory mapping API

[Alexandre Bounine]

Add RapidIO subsystem interface to support mapping of RapidIO memory space into
system's local memory. 

RapidIO specification defines memory mapped read (NREAD) and write (NWRITE,
NWRITE_R and SWRITE) requests that allow to access memory space on remote target
device. Existing RapidIO controllers/bridges provide hardware mechanism
to map addresses on RapidIO side into system's local memory. Patches provided in
this package define common interface that has to be supported by RIO master port
devices and hardware dependent implementation for IDT Tsi721 PCIe-to-SRIO bridge.

These patches are based on the work submitted by Li Yang <leoli@freescale.com>
(https://lists.ozlabs.org/pipermail/linuxppc-dev/2009-April/071210.html) but
implement only the inbound mapping portion of it.

Combined with RapidIO DMA engine interface support these patches allow to perform
memory mapped data transfers between devices connected to a RapidIO network.  

Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
---
Alexandre Bounine (2):
  rapidio: add inbound memory mapping interface
  rapidio/tsi721: add inbound memory mapping callbacks

 drivers/rapidio/devices/tsi721.c |   88 +++++++++++++++++++++++++++++++++++++-
 drivers/rapidio/devices/tsi721.h |   15 +++++-
 drivers/rapidio/rio.c            |   44 +++++++++++++++++++
 include/linux/rio.h              |    5 ++
 include/linux/rio_drv.h          |    5 ++
 5 files changed, 153 insertions(+), 4 deletions(-)

-- 
1.7.8.4

[PATCH 1/2] rapidio: add inbound memory mapping interface

[Alexandre Bounine]

Add common inbound memory mapping/unmapping interface. This allows to make
local memory space accessible from the RapidIO side using hardware mapping
capabilities of RapidIO bridging devices. The new interface is intended to
enable data transfers between RapidIO devices in combination with DMA engine
support. 

This patch is based on patch submitted by Li Yang <leoli@freescale.com>
(https://lists.ozlabs.org/pipermail/linuxppc-dev/2009-April/071210.html)

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
---
 drivers/rapidio/rio.c   |   44 ++++++++++++++++++++++++++++++++++++++++++++
 include/linux/rio.h     |    5 +++++
 include/linux/rio_drv.h |    5 +++++
 3 files changed, 54 insertions(+), 0 deletions(-)

diff --git a/drivers/rapidio/rio.c b/drivers/rapidio/rio.c
index c40665a..d7b68cc 100644
--- a/drivers/rapidio/rio.c
+++ b/drivers/rapidio/rio.c
@@ -33,6 +33,7 @@
 
 static LIST_HEAD(rio_mports);
 static unsigned char next_portid;
+static DEFINE_SPINLOCK(rio_mmap_lock);
 
 /**
  * rio_local_get_device_id - Get the base/extended device id for a port
@@ -398,6 +399,49 @@ int rio_release_inb_pwrite(struct rio_dev *rdev)
 EXPORT_SYMBOL_GPL(rio_release_inb_pwrite);
 
 /**
+ * rio_map_inb_region -- Map inbound memory region.
+ * @mport: Master port.
+ * @lstart: physical address of memory region to be mapped
+ * @rbase: RIO base address assigned to this window
+ * @size: Size of the memory region
+ * @rflags: Flags for mapping.
+ *
+ * Return: 0 -- Success.
+ *
+ * This function will create the mapping from RIO space to local memory.
+ */
+int rio_map_inb_region(struct rio_mport *mport, dma_addr_t local,
+			u64 rbase, u32 size, u32 rflags)
+{
+	int rc = 0;
+	unsigned long flags;
+
+	if (!mport->ops->map_inb)
+		return -1;
+	spin_lock_irqsave(&rio_mmap_lock, flags);
+	rc = mport->ops->map_inb(mport, local, rbase, size, rflags);
+	spin_unlock_irqrestore(&rio_mmap_lock, flags);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(rio_map_inb_region);
+
+/**
+ * rio_unmap_inb_region -- Unmap the inbound memory region
+ * @mport: Master port
+ * @lstart: physical address of memory region to be unmapped
+ */
+void rio_unmap_inb_region(struct rio_mport *mport, dma_addr_t lstart)
+{
+	unsigned long flags;
+	if (!mport->ops->unmap_inb)
+		return;
+	spin_lock_irqsave(&rio_mmap_lock, flags);
+	mport->ops->unmap_inb(mport, lstart);
+	spin_unlock_irqrestore(&rio_mmap_lock, flags);
+}
+EXPORT_SYMBOL_GPL(rio_unmap_inb_region);
+
+/**
  * rio_mport_get_physefb - Helper function that returns register offset
  *                      for Physical Layer Extended Features Block.
  * @port: Master port to issue transaction
diff --git a/include/linux/rio.h b/include/linux/rio.h
index ba382f2..4d1a104 100644
--- a/include/linux/rio.h
+++ b/include/linux/rio.h
@@ -301,6 +301,8 @@ struct rio_net {
  * @add_outb_message: Callback to add a message to an outbound mailbox queue.
  * @add_inb_buffer: Callback to	add a buffer to an inbound mailbox queue.
  * @get_inb_message: Callback to get a message from an inbound mailbox queue.
+ * @map_inb: Callback to map RapidIO address region into local memory space.
+ * @unmap_inb: Callback to unmap RapidIO address region mapped with map_inb().
  */
 struct rio_ops {
 	int (*lcread) (struct rio_mport *mport, int index, u32 offset, int len,
@@ -323,6 +325,9 @@ struct rio_ops {
 				 int mbox, void *buffer, size_t len);
 	int (*add_inb_buffer)(struct rio_mport *mport, int mbox, void *buf);
 	void *(*get_inb_message)(struct rio_mport *mport, int mbox);
+	int (*map_inb)(struct rio_mport *mport, dma_addr_t lstart,
+			u64 rstart, u32 size, u32 flags);
+	void (*unmap_inb)(struct rio_mport *mport, dma_addr_t lstart);
 };
 
 #define RIO_RESOURCE_MEM	0x00000100
diff --git a/include/linux/rio_drv.h b/include/linux/rio_drv.h
index 31ad146..b75c059 100644
--- a/include/linux/rio_drv.h
+++ b/include/linux/rio_drv.h
@@ -365,6 +365,11 @@ void rio_release_regions(struct rio_dev *);
 int rio_request_region(struct rio_dev *, int, char *);
 void rio_release_region(struct rio_dev *, int);
 
+/* Memory mapping functions */
+extern int rio_map_inb_region(struct rio_mport *mport, dma_addr_t local,
+			u64 rbase, u32 size, u32 rflags);
+extern void rio_unmap_inb_region(struct rio_mport *mport, dma_addr_t lstart);
+
 /* Port-Write management */
 extern int rio_request_inb_pwrite(struct rio_dev *,
 			int (*)(struct rio_dev *, union rio_pw_msg*, int));
-- 
1.7.8.4

[PATCH 2/2] rapidio/tsi721: add inbound memory mapping callbacks

[Alexandre Bounine]

Add Tsi721 routines to support RapidIO subsystem's inbound memory mapping
interface (RapidIO to system's local memory). 

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
---
 drivers/rapidio/devices/tsi721.c |   88 +++++++++++++++++++++++++++++++++++++-
 drivers/rapidio/devices/tsi721.h |   15 +++++-
 2 files changed, 99 insertions(+), 4 deletions(-)

diff --git a/drivers/rapidio/devices/tsi721.c b/drivers/rapidio/devices/tsi721.c
index 1974359..961dc7a 100644
--- a/drivers/rapidio/devices/tsi721.c
+++ b/drivers/rapidio/devices/tsi721.c
@@ -862,6 +862,90 @@ static void tsi721_init_pc2sr_mapping(struct tsi721_device *priv)
 }
 
 /**
+ * tsi721_rio_map_inb_mem -- Mapping inbound memory region.
+ * @mport: RapidIO master port
+ * @lstart: Local memory space start address.
+ * @rstart: RapidIO space start address.
+ * @size: The mapping region size.
+ * @flags: Flags for mapping. 0 for using default flags.
+ *
+ * Return: 0 -- Success.
+ *
+ * This function will create the inbound mapping
+ * from rstart to lstart.
+ */
+static int tsi721_rio_map_inb_mem(struct rio_mport *mport, dma_addr_t lstart,
+		u64 rstart, u32 size, u32 flags)
+{
+	struct tsi721_device *priv = mport->priv;
+	int i;
+	u32 regval;
+
+	if (!is_power_of_2(size) || size < 0x1000 ||
+	    ((u64)lstart & (size - 1)) || (rstart & (size - 1)))
+		return -EINVAL;
+
+	/* Search for free inbound translation window */
+	for (i = 0; i < TSI721_IBWIN_NUM; i++) {
+		regval = ioread32(priv->regs + TSI721_IBWIN_LB(i));
+		if (!(regval & TSI721_IBWIN_LB_WEN))
+			break;
+	}
+
+	if (i >= TSI721_IBWIN_NUM) {
+		dev_err(&priv->pdev->dev,
+			"Unable to find free inbound window\n");
+		return -EBUSY;
+	}
+
+	iowrite32(TSI721_IBWIN_SIZE(size) << 8,
+			priv->regs + TSI721_IBWIN_SZ(i));
+
+	iowrite32(((u64)lstart >> 32), priv->regs + TSI721_IBWIN_TUA(i));
+	iowrite32(((u64)lstart & TSI721_IBWIN_TLA_ADD),
+		  priv->regs + TSI721_IBWIN_TLA(i));
+
+	iowrite32(rstart >> 32, priv->regs + TSI721_IBWIN_UB(i));
+	iowrite32((rstart & TSI721_IBWIN_LB_BA) | TSI721_IBWIN_LB_WEN,
+		priv->regs + TSI721_IBWIN_LB(i));
+	dev_dbg(&priv->pdev->dev,
+		"Configured IBWIN%d mapping (RIO_0x%llx -> PCIe_0x%llx)\n",
+		i, rstart, (unsigned long long)lstart);
+
+	return 0;
+}
+
+/**
+ * fsl_rio_unmap_inb_mem -- Unmapping inbound memory region.
+ * @mport: RapidIO master port
+ * @lstart: Local memory space start address.
+ */
+static void tsi721_rio_unmap_inb_mem(struct rio_mport *mport,
+				dma_addr_t lstart)
+{
+	struct tsi721_device *priv = mport->priv;
+	int i;
+	u64 addr;
+	u32 regval;
+
+	/* Search for matching active inbound translation window */
+	for (i = 0; i < TSI721_IBWIN_NUM; i++) {
+		regval = ioread32(priv->regs + TSI721_IBWIN_LB(i));
+		if (regval & TSI721_IBWIN_LB_WEN) {
+			regval = ioread32(priv->regs + TSI721_IBWIN_TUA(i));
+			addr = (u64)regval << 32;
+			regval = ioread32(priv->regs + TSI721_IBWIN_TLA(i));
+			addr |= regval & TSI721_IBWIN_TLA_ADD;
+
+			if (addr == (u64)lstart) {
+				iowrite32(0, priv->regs + TSI721_IBWIN_LB(i));
+				break;
+			}
+		}
+	}
+}
+
+/**
  * tsi721_init_sr2pc_mapping - initializes inbound (SRIO->PCIe)
  * translation regions.
  * @priv: pointer to tsi721 private data
@@ -874,7 +958,7 @@ static void tsi721_init_sr2pc_mapping(struct tsi721_device *priv)
 
 	/* Disable all SR2PC inbound windows */
 	for (i = 0; i < TSI721_IBWIN_NUM; i++)
-		iowrite32(0, priv->regs + TSI721_IBWINLB(i));
+		iowrite32(0, priv->regs + TSI721_IBWIN_LB(i));
 }
 
 /**
@@ -2144,6 +2228,8 @@ static int __devinit tsi721_setup_mport(struct tsi721_device *priv)
 	ops->add_outb_message = tsi721_add_outb_message;
 	ops->add_inb_buffer = tsi721_add_inb_buffer;
 	ops->get_inb_message = tsi721_get_inb_message;
+	ops->map_inb = tsi721_rio_map_inb_mem;
+	ops->unmap_inb = tsi721_rio_unmap_inb_mem;
 
 	mport = kzalloc(sizeof(struct rio_mport), GFP_KERNEL);
 	if (!mport) {
diff --git a/drivers/rapidio/devices/tsi721.h b/drivers/rapidio/devices/tsi721.h
index 59de9d7..7d5b13b 100644
--- a/drivers/rapidio/devices/tsi721.h
+++ b/drivers/rapidio/devices/tsi721.h
@@ -156,9 +156,18 @@
 
 #define TSI721_IBWIN_NUM	8
 
-#define TSI721_IBWINLB(x)	(0x29000 + (x) * 0x20)
-#define TSI721_IBWINLB_BA	0xfffff000
-#define TSI721_IBWINLB_WEN	0x00000001
+#define TSI721_IBWIN_LB(x)	(0x29000 + (x) * 0x20)
+#define TSI721_IBWIN_LB_BA	0xfffff000
+#define TSI721_IBWIN_LB_WEN	0x00000001
+
+#define TSI721_IBWIN_UB(x)	(0x29004 + (x) * 0x20)
+#define TSI721_IBWIN_SZ(x)	(0x29008 + (x) * 0x20)
+#define TSI721_IBWIN_SZ_SIZE	0x00001f00
+#define TSI721_IBWIN_SIZE(size)	(__fls(size) - 12)
+
+#define TSI721_IBWIN_TLA(x)	(0x2900c + (x) * 0x20)
+#define TSI721_IBWIN_TLA_ADD	0xfffff000
+#define TSI721_IBWIN_TUA(x)	(0x29010 + (x) * 0x20)
 
 #define TSI721_SR2PC_GEN_INTE	0x29800
 #define TSI721_SR2PC_PWE	0x29804
-- 
1.7.8.4