Support setting payload size

8 files changed, 88 insertions, 8 deletions

diff --git a/driver/Makefile b/driver/Makefile
index 3a242dd..83a8c46 100644
--- a/driver/Makefile
+++ b/driver/Makefile
@@ -1,6 +1,6 @@
 
 obj-m := pciDriver.o
-pciDriver-objs := base.o int.o umem.o kmem.o sysfs.o ioctl.o
+pciDriver-objs := base.o int.o umem.o kmem.o sysfs.o ioctl.o compat.o
 
 KERNELDIR ?= /lib/modules/$(shell uname -r)/build
 INSTALLDIR ?= /lib/modules/$(shell uname -r)/kernel/extra
diff --git a/driver/compat.c b/driver/compat.c
new file mode 100644
index 0000000..a632781
--- /dev/null
+++ b/driver/compat.c
@@ -0,0 +1,26 @@
+#include <linux/pci.h>
+
+int pcidriver_pcie_get_mps(struct pci_dev *dev)
+{
+        u16 ctl;
+
+        pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
+
+        return 128 << ((ctl & PCI_EXP_DEVCTL_PAYLOAD) >> 5);
+}
+
+int pcidriver_pcie_set_mps(struct pci_dev *dev, int mps)
+{
+        u16 v;
+
+        if (mps < 128 || mps > 4096 || !is_power_of_2(mps))
+                return -EINVAL;
+
+        v = ffs(mps) - 8;
+        if (v > dev->pcie_mpss)
+                return -EINVAL;
+        v <<= 5;
+
+        return pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL,
+                                                  PCI_EXP_DEVCTL_PAYLOAD, v);
+}
diff --git a/driver/compat.h b/driver/compat.h
index 25e402a..fd3f188 100644
--- a/driver/compat.h
+++ b/driver/compat.h
@@ -195,4 +195,7 @@ static inline void set_pages_reserved_compat(unsigned long cpua, unsigned long s
 #endif
 }
 
+int pcidriver_pcie_get_mps(struct pci_dev *dev);
+int pcidriver_pcie_set_mps(struct pci_dev *dev, int mps);
+
 #endif
diff --git a/driver/ioctl.c b/driver/ioctl.c
index e003476..67cdc52 100644
--- a/driver/ioctl.c
+++ b/driver/ioctl.c
@@ -433,7 +433,6 @@ static int ioctl_version(pcidriver_privdata_t *privdata, unsigned long arg)
 	return 0;
 }
 
-
 /**
  *
  * Gets current device and driver configuration
@@ -448,6 +447,7 @@ static int ioctl_device_state(pcidriver_privdata_t *privdata, unsigned long arg)
 
 	info = (pcilib_device_state_t) {
 	    .iommu = iommu_present(privdata->pdev->dev.bus),
+	    .mps = pcidriver_pcie_get_mps(privdata->pdev),
 	    .dma_mask = privdata->pdev->dma_mask
 	};
 
@@ -468,7 +468,7 @@ static int ioctl_set_dma_mask(pcidriver_privdata_t *privdata, unsigned long arg)
 {
 	int err;
 
-	if ((arg < 24) && (arg > 63))
+	if ((arg < 24) || (arg > 64))
 		return -EINVAL;
 
 	err = pci_set_dma_mask(privdata->pdev, DMA_BIT_MASK(arg));
@@ -477,8 +477,29 @@ static int ioctl_set_dma_mask(pcidriver_privdata_t *privdata, unsigned long arg)
 	    return err;
 	}
 	
-	printk(KERN_ERR "pci_set_dma_mask(%lu) successeded\n", arg);
+	return 0;
+}
+
+/**
+ *
+ * Sets Max Payload Size.
+ *
+ * @param arg Not a pointer, but payload size in bits
+ *
+ */
+static int ioctl_set_mps(pcidriver_privdata_t *privdata, unsigned long arg)
+{
+	int err;
 
+	if ((arg != 128) && (arg != 256) && (arg != 512))
+		return -EINVAL;
+
+	err = pcidriver_pcie_set_mps(privdata->pdev, arg);
+	if (err < 0) {
+	    printk(KERN_ERR "pcie_set_mps(%lu) failed\n", arg);
+	    return err;
+	}
+	
 	return 0;
 }
 
@@ -551,6 +572,9 @@ long pcidriver_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 		case PCIDRIVER_IOC_DMA_MASK:
 			return ioctl_set_dma_mask(privdata, arg);
 
+		case PCIDRIVER_IOC_MPS:
+			return ioctl_set_mps(privdata, arg);
+
 		default:
 			return -EINVAL;
 	}
diff --git a/driver/pciDriver.h b/driver/pciDriver.h
index d314952..2fda0ff 100644
--- a/driver/pciDriver.h
+++ b/driver/pciDriver.h
@@ -130,8 +130,9 @@ typedef struct {
 } pcilib_driver_version_t;
 
 typedef struct {
-    unsigned long iommu;
-    unsigned long dma_mask;
+    int iommu;						/**< Specifies if IOMMU is enabled or disabled */
+    int mps;						/**< Maximum payload size */
+    unsigned long dma_mask;				/**< DMA mask */
 } pcilib_device_state_t;
 
 typedef struct {
@@ -235,7 +236,8 @@ typedef struct {
 #define PCIDRIVER_IOC_VERSION		_IOR(  PCIDRIVER_IOC_MAGIC, PCIDRIVER_IOC_BASE + 14, pcilib_driver_version_t * )
 #define PCIDRIVER_IOC_DEVICE_STATE	_IOR(  PCIDRIVER_IOC_MAGIC, PCIDRIVER_IOC_BASE + 15, pcilib_device_state_t * )
 #define PCIDRIVER_IOC_DMA_MASK		_IO(   PCIDRIVER_IOC_MAGIC, PCIDRIVER_IOC_BASE + 16)
+#define PCIDRIVER_IOC_MPS		_IO(   PCIDRIVER_IOC_MAGIC, PCIDRIVER_IOC_BASE + 17)
 
-#define PCIDRIVER_IOC_MAX 16
+#define PCIDRIVER_IOC_MAX 17
 
 #endif
diff --git a/pcilib/pci.c b/pcilib/pci.c
index 26dfdbf..eaf41ac 100644
--- a/pcilib/pci.c
+++ b/pcilib/pci.c
@@ -483,3 +483,10 @@ int pcilib_set_dma_mask(pcilib_t *ctx, int mask) {
 
     return 0;
 }
+
+int pcilib_set_mps(pcilib_t *ctx, int mps) {
+    if (ioctl(ctx->handle, PCIDRIVER_IOC_MPS, mps) < 0)
+	return PCILIB_ERROR_FAILED;
+
+    return 0;
+}
diff --git a/pcilib/pci.h b/pcilib/pci.h
index b81d295..43de485 100644
--- a/pcilib/pci.h
+++ b/pcilib/pci.h
@@ -124,6 +124,7 @@ int pcilib_map_register_space(pcilib_t *ctx);
 int pcilib_map_data_space(pcilib_t *ctx, uintptr_t addr);
 
 int pcilib_set_dma_mask(pcilib_t *ctx, int mask);
+int pcilib_set_mps(pcilib_t *ctx, int mps);
 
 #ifdef __cplusplus
 }
diff --git a/pcitool/cli.c b/pcitool/cli.c
index 65e24dc..dbc7f47 100644
--- a/pcitool/cli.c
+++ b/pcitool/cli.c
@@ -97,6 +97,7 @@ typedef enum {
     MODE_ACK_IRQ,
     MODE_WAIT_IRQ,
     MODE_SET_DMASK,
+    MODE_SET_MPS,
     MODE_ALLOC_KMEM,
     MODE_LIST_KMEM,
     MODE_READ_KMEM,
@@ -173,6 +174,7 @@ typedef enum {
     OPT_WAIT_IRQ,
     OPT_ITERATIONS,
     OPT_SET_DMASK,
+    OPT_SET_MPS,
     OPT_ALLOC_KMEM,
     OPT_LIST_KMEM,
     OPT_FREE_KMEM,
@@ -227,6 +229,7 @@ static struct option long_options[] = {
     {"acknowledge-irq",		optional_argument, 0, OPT_ACK_IRQ },
     {"wait-irq",		optional_argument, 0, OPT_WAIT_IRQ },
     {"set-dma-mask",		required_argument, 0, OPT_SET_DMASK },
+    {"set-mps",			required_argument, 0, OPT_SET_MPS },
     {"list-kernel-memory",	optional_argument, 0, OPT_LIST_KMEM },
     {"read-kernel-memory",	required_argument, 0, OPT_READ_KMEM },
     {"alloc-kernel-memory",	required_argument, 0, OPT_ALLOC_KMEM },
@@ -303,8 +306,11 @@ void Usage(int argc, char *argv[], const char *format, ...) {
 "   --list-dma-buffers <dma>	- List buffers for specified DMA engine\n"
 "   --read-dma-buffer <dma:buf>	- Read the specified buffer\n"
 "\n"
-"  Kernel Modes:\n"
+"  PCI Configuration:\n"
 "   --set-dma-mask [bits]	- Set DMA address width (DANGEROUS)\n"
+"   --set-mps [bits]		- Set PCIe Payload Size (DANGEROUS)\n"
+"\n"
+"  Kernel Memory Modes:\n"
 "   --list-kernel-memory [use] 	- List kernel buffers\n"
 "   --read-kernel-memory <blk>	- Read the specified block of the kernel memory\n"
 "				  block is specified as: use:block_number\n"
@@ -3089,6 +3095,7 @@ int main(int argc, char **argv) {
     size_t iterations = BENCHMARK_ITERATIONS;
 
     unsigned long dma_mask = 0;
+    unsigned long pcie_mps = 0;
 
     pcilib_t *handle;
 
@@ -3290,6 +3297,13 @@ int main(int argc, char **argv) {
 		if ((!isnumber(optarg))||(sscanf(optarg, "%lu", &dma_mask) != 1)||(dma_mask<24)||(dma_mask>64))
 			Usage(argc, argv, "Invalid DMA mask is specified (%s)", optarg);
 	    break;
+	    case OPT_SET_MPS:
+		if (mode != MODE_INVALID) Usage(argc, argv, "Multiple operations are not supported");
+		mode = MODE_SET_MPS;
+
+		if ((!isnumber(optarg))||(sscanf(optarg, "%lu", &pcie_mps) != 1)||(pcie_mps<128)||(pcie_mps>2048))
+			Usage(argc, argv, "Invalid payload size is specified (%s)", optarg);
+	    break;
 	    case OPT_LIST_KMEM:
 		if (mode != MODE_INVALID) Usage(argc, argv, "Multiple operations are not supported");
 		mode = MODE_LIST_KMEM;
@@ -3888,6 +3902,9 @@ int main(int argc, char **argv) {
      case MODE_SET_DMASK:
         pcilib_set_dma_mask(handle, dma_mask);
      break;
+     case MODE_SET_MPS:
+        pcilib_set_mps(handle, pcie_mps);
+     break;
      case MODE_LIST_KMEM:
         if (use) DetailKMEM(handle, fpga_device, use, block);
         else ListKMEM(handle, fpga_device);