Merge branch 'ioat' into fixes

11 files changed, 179 insertions, 55 deletions

diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index fe93d70..93b058f 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -26,6 +26,8 @@ config INTEL_IOATDMA
 	select DMA_ENGINE
 	select DCA
 	select ASYNC_TX_DISABLE_CHANNEL_SWITCH
+	select ASYNC_TX_DISABLE_PQ_VAL_DMA
+	select ASYNC_TX_DISABLE_XOR_VAL_DMA
 	help
 	  Enable support for the Intel(R) I/OAT DMA engine present
 	  in recent Intel Xeon chipsets.
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index bd0b248..8f99354 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -632,11 +632,21 @@ static bool device_has_all_tx_types(struct dma_device *device)
 	#if defined(CONFIG_ASYNC_XOR) || defined(CONFIG_ASYNC_XOR_MODULE)
 	if (!dma_has_cap(DMA_XOR, device->cap_mask))
 		return false;
+
+	#ifndef CONFIG_ASYNC_TX_DISABLE_XOR_VAL_DMA
+	if (!dma_has_cap(DMA_XOR_VAL, device->cap_mask))
+		return false;
+	#endif
 	#endif
 
 	#if defined(CONFIG_ASYNC_PQ) || defined(CONFIG_ASYNC_PQ_MODULE)
 	if (!dma_has_cap(DMA_PQ, device->cap_mask))
 		return false;
+
+	#ifndef CONFIG_ASYNC_TX_DISABLE_PQ_VAL_DMA
+	if (!dma_has_cap(DMA_PQ_VAL, device->cap_mask))
+		return false;
+	#endif
 	#endif
 
 	return true;
diff --git a/drivers/dma/ioat/dca.c b/drivers/dma/ioat/dca.c
index 69d0261..abd9038 100644
--- a/drivers/dma/ioat/dca.c
+++ b/drivers/dma/ioat/dca.c
@@ -98,17 +98,17 @@ static int dca_enabled_in_bios(struct pci_dev *pdev)
 	cpuid_level_9 = cpuid_eax(9);
 	res = test_bit(0, &cpuid_level_9);
 	if (!res)
-		dev_err(&pdev->dev, "DCA is disabled in BIOS\n");
+		dev_dbg(&pdev->dev, "DCA is disabled in BIOS\n");
 
 	return res;
 }
 
-static int system_has_dca_enabled(struct pci_dev *pdev)
+int system_has_dca_enabled(struct pci_dev *pdev)
 {
 	if (boot_cpu_has(X86_FEATURE_DCA))
 		return dca_enabled_in_bios(pdev);
 
-	dev_err(&pdev->dev, "boot cpu doesn't have X86_FEATURE_DCA\n");
+	dev_dbg(&pdev->dev, "boot cpu doesn't have X86_FEATURE_DCA\n");
 	return 0;
 }
 
diff --git a/drivers/dma/ioat/dma.c b/drivers/dma/ioat/dma.c
index c524d36..dcc4ab7 100644
--- a/drivers/dma/ioat/dma.c
+++ b/drivers/dma/ioat/dma.c
@@ -1032,7 +1032,7 @@ int __devinit ioat_probe(struct ioatdma_device *device)
 	dma->dev = &pdev->dev;
 
 	if (!dma->chancnt) {
-		dev_err(dev, "zero channels detected\n");
+		dev_err(dev, "channel enumeration error\n");
 		goto err_setup_interrupts;
 	}
 
diff --git a/drivers/dma/ioat/dma.h b/drivers/dma/ioat/dma.h
index c14fdfe..bbc3e78 100644
--- a/drivers/dma/ioat/dma.h
+++ b/drivers/dma/ioat/dma.h
@@ -60,6 +60,7 @@
  * @dca: direct cache access context
  * @intr_quirk: interrupt setup quirk (for ioat_v1 devices)
  * @enumerate_channels: hw version specific channel enumeration
+ * @reset_hw: hw version specific channel (re)initialization
  * @cleanup_tasklet: select between the v2 and v3 cleanup routines
  * @timer_fn: select between the v2 and v3 timer watchdog routines
  * @self_test: hardware version specific self test for each supported op type
@@ -78,6 +79,7 @@ struct ioatdma_device {
 	struct dca_provider *dca;
 	void (*intr_quirk)(struct ioatdma_device *device);
 	int (*enumerate_channels)(struct ioatdma_device *device);
+	int (*reset_hw)(struct ioat_chan_common *chan);
 	void (*cleanup_tasklet)(unsigned long data);
 	void (*timer_fn)(unsigned long data);
 	int (*self_test)(struct ioatdma_device *device);
@@ -264,6 +266,22 @@ static inline void ioat_suspend(struct ioat_chan_common *chan)
 	writeb(IOAT_CHANCMD_SUSPEND, chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
 }
 
+static inline void ioat_reset(struct ioat_chan_common *chan)
+{
+	u8 ver = chan->device->version;
+
+	writeb(IOAT_CHANCMD_RESET, chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
+}
+
+static inline bool ioat_reset_pending(struct ioat_chan_common *chan)
+{
+	u8 ver = chan->device->version;
+	u8 cmd;
+
+	cmd = readb(chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
+	return (cmd & IOAT_CHANCMD_RESET) == IOAT_CHANCMD_RESET;
+}
+
 static inline void ioat_set_chainaddr(struct ioat_dma_chan *ioat, u64 addr)
 {
 	struct ioat_chan_common *chan = &ioat->base;
@@ -297,9 +315,7 @@ static inline bool is_ioat_suspended(unsigned long status)
 /* channel was fatally programmed */
 static inline bool is_ioat_bug(unsigned long err)
 {
-	return !!(err & (IOAT_CHANERR_SRC_ADDR_ERR|IOAT_CHANERR_DEST_ADDR_ERR|
-			 IOAT_CHANERR_NEXT_ADDR_ERR|IOAT_CHANERR_CONTROL_ERR|
-			 IOAT_CHANERR_LENGTH_ERR));
+	return !!err;
 }
 
 static inline void ioat_unmap(struct pci_dev *pdev, dma_addr_t addr, size_t len,
diff --git a/drivers/dma/ioat/dma_v2.c b/drivers/dma/ioat/dma_v2.c
index 96ffab7..5f7a500 100644
--- a/drivers/dma/ioat/dma_v2.c
+++ b/drivers/dma/ioat/dma_v2.c
@@ -239,20 +239,50 @@ void __ioat2_restart_chan(struct ioat2_dma_chan *ioat)
 		__ioat2_start_null_desc(ioat);
 }
 
-static void ioat2_restart_channel(struct ioat2_dma_chan *ioat)
+int ioat2_quiesce(struct ioat_chan_common *chan, unsigned long tmo)
 {
-	struct ioat_chan_common *chan = &ioat->base;
-	unsigned long phys_complete;
+	unsigned long end = jiffies + tmo;
+	int err = 0;
 	u32 status;
 
 	status = ioat_chansts(chan);
 	if (is_ioat_active(status) || is_ioat_idle(status))
 		ioat_suspend(chan);
 	while (is_ioat_active(status) || is_ioat_idle(status)) {
+		if (end && time_after(jiffies, end)) {
+			err = -ETIMEDOUT;
+			break;
+		}
 		status = ioat_chansts(chan);
 		cpu_relax();
 	}
 
+	return err;
+}
+
+int ioat2_reset_sync(struct ioat_chan_common *chan, unsigned long tmo)
+{
+	unsigned long end = jiffies + tmo;
+	int err = 0;
+
+	ioat_reset(chan);
+	while (ioat_reset_pending(chan)) {
+		if (end && time_after(jiffies, end)) {
+			err = -ETIMEDOUT;
+			break;
+		}
+		cpu_relax();
+	}
+
+	return err;
+}
+
+static void ioat2_restart_channel(struct ioat2_dma_chan *ioat)
+{
+	struct ioat_chan_common *chan = &ioat->base;
+	unsigned long phys_complete;
+
+	ioat2_quiesce(chan, 0);
 	if (ioat_cleanup_preamble(chan, &phys_complete))
 		__cleanup(ioat, phys_complete);
 
@@ -279,6 +309,8 @@ void ioat2_timer_event(unsigned long data)
 			u32 chanerr;
 
 			chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET);
+			dev_err(to_dev(chan), "%s: Channel halted (%x)\n",
+				__func__, chanerr);
 			BUG_ON(is_ioat_bug(chanerr));
 		}
 
@@ -316,6 +348,19 @@ void ioat2_timer_event(unsigned long data)
 	spin_unlock_bh(&chan->cleanup_lock);
 }
 
+static int ioat2_reset_hw(struct ioat_chan_common *chan)
+{
+	/* throw away whatever the channel was doing and get it initialized */
+	u32 chanerr;
+
+	ioat2_quiesce(chan, msecs_to_jiffies(100));
+
+	chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET);
+	writel(chanerr, chan->reg_base + IOAT_CHANERR_OFFSET);
+
+	return ioat2_reset_sync(chan, msecs_to_jiffies(200));
+}
+
 /**
  * ioat2_enumerate_channels - find and initialize the device's channels
  * @device: the device to be enumerated
@@ -358,6 +403,10 @@ int ioat2_enumerate_channels(struct ioatdma_device *device)
 				  (unsigned long) ioat);
 		ioat->xfercap_log = xfercap_log;
 		spin_lock_init(&ioat->ring_lock);
+		if (device->reset_hw(&ioat->base)) {
+			i = 0;
+			break;
+		}
 	}
 	dma->chancnt = i;
 	return i;
@@ -465,7 +514,6 @@ int ioat2_alloc_chan_resources(struct dma_chan *c)
 	struct ioat2_dma_chan *ioat = to_ioat2_chan(c);
 	struct ioat_chan_common *chan = &ioat->base;
 	struct ioat_ring_ent **ring;
-	u32 chanerr;
 	int order;
 
 	/* have we already been set up? */
@@ -475,12 +523,6 @@ int ioat2_alloc_chan_resources(struct dma_chan *c)
 	/* Setup register to interrupt and write completion status on error */
 	writew(IOAT_CHANCTRL_RUN, chan->reg_base + IOAT_CHANCTRL_OFFSET);
 
-	chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET);
-	if (chanerr) {
-		dev_err(to_dev(chan), "CHANERR = %x, clearing\n", chanerr);
-		writel(chanerr, chan->reg_base + IOAT_CHANERR_OFFSET);
-	}
-
 	/* allocate a completion writeback area */
 	/* doing 2 32bit writes to mmio since 1 64b write doesn't work */
 	chan->completion = pci_pool_alloc(chan->device->completion_pool,
@@ -744,13 +786,7 @@ void ioat2_free_chan_resources(struct dma_chan *c)
 	tasklet_disable(&chan->cleanup_task);
 	del_timer_sync(&chan->timer);
 	device->cleanup_tasklet((unsigned long) ioat);
-
-	/* Delay 100ms after reset to allow internal DMA logic to quiesce
-	 * before removing DMA descriptor resources.
-	 */
-	writeb(IOAT_CHANCMD_RESET,
-	       chan->reg_base + IOAT_CHANCMD_OFFSET(chan->device->version));
-	mdelay(100);
+	device->reset_hw(chan);
 
 	spin_lock_bh(&ioat->ring_lock);
 	descs = ioat2_ring_space(ioat);
@@ -837,6 +873,7 @@ int __devinit ioat2_dma_probe(struct ioatdma_device *device, int dca)
 	int err;
 
 	device->enumerate_channels = ioat2_enumerate_channels;
+	device->reset_hw = ioat2_reset_hw;
 	device->cleanup_tasklet = ioat2_cleanup_tasklet;
 	device->timer_fn = ioat2_timer_event;
 	device->self_test = ioat_dma_self_test;
diff --git a/drivers/dma/ioat/dma_v2.h b/drivers/dma/ioat/dma_v2.h
index 1d849ef..3afad8d 100644
--- a/drivers/dma/ioat/dma_v2.h
+++ b/drivers/dma/ioat/dma_v2.h
@@ -185,6 +185,8 @@ bool reshape_ring(struct ioat2_dma_chan *ioat, int order);
 void __ioat2_issue_pending(struct ioat2_dma_chan *ioat);
 void ioat2_cleanup_tasklet(unsigned long data);
 void ioat2_timer_event(unsigned long data);
+int ioat2_quiesce(struct ioat_chan_common *chan, unsigned long tmo);
+int ioat2_reset_sync(struct ioat_chan_common *chan, unsigned long tmo);
 extern struct kobj_type ioat2_ktype;
 extern struct kmem_cache *ioat2_cache;
 #endif /* IOATDMA_V2_H */
diff --git a/drivers/dma/ioat/dma_v3.c b/drivers/dma/ioat/dma_v3.c
index 35d1e33..9908c9e 100644
--- a/drivers/dma/ioat/dma_v3.c
+++ b/drivers/dma/ioat/dma_v3.c
@@ -378,6 +378,8 @@ static void ioat3_timer_event(unsigned long data)
 			u32 chanerr;
 
 			chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET);
+			dev_err(to_dev(chan), "%s: Channel halted (%x)\n",
+				__func__, chanerr);
 			BUG_ON(is_ioat_bug(chanerr));
 		}
 
@@ -569,7 +571,7 @@ __ioat3_prep_xor_lock(struct dma_chan *c, enum sum_check_flags *result,
 	dump_desc_dbg(ioat, compl_desc);
 
 	/* we leave the channel locked to ensure in order submission */
-	return &desc->txd;
+	return &compl_desc->txd;
 }
 
 static struct dma_async_tx_descriptor *
@@ -648,9 +650,11 @@ __ioat3_prep_pq_lock(struct dma_chan *c, enum sum_check_flags *result,
 
 	num_descs = ioat2_xferlen_to_descs(ioat, len);
 	/* we need 2x the number of descriptors to cover greater than 3
-	 * sources
+	 * sources (we need 1 extra source in the q-only continuation
+	 * case and 3 extra sources in the p+q continuation case.
 	 */
-	if (src_cnt > 3 || flags & DMA_PREP_CONTINUE) {
+	if (src_cnt + dmaf_p_disabled_continue(flags) > 3 ||
+	    (dmaf_continue(flags) && !dmaf_p_disabled_continue(flags))) {
 		with_ext = 1;
 		num_descs *= 2;
 	} else
@@ -728,7 +732,7 @@ __ioat3_prep_pq_lock(struct dma_chan *c, enum sum_check_flags *result,
 	dump_desc_dbg(ioat, compl_desc);
 
 	/* we leave the channel locked to ensure in order submission */
-	return &desc->txd;
+	return &compl_desc->txd;
 }
 
 static struct dma_async_tx_descriptor *
@@ -736,10 +740,16 @@ ioat3_prep_pq(struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
 	      unsigned int src_cnt, const unsigned char *scf, size_t len,
 	      unsigned long flags)
 {
+	/* specify valid address for disabled result */
+	if (flags & DMA_PREP_PQ_DISABLE_P)
+		dst[0] = dst[1];
+	if (flags & DMA_PREP_PQ_DISABLE_Q)
+		dst[1] = dst[0];
+
 	/* handle the single source multiply case from the raid6
 	 * recovery path
 	 */
-	if (unlikely((flags & DMA_PREP_PQ_DISABLE_P) && src_cnt == 1)) {
+	if ((flags & DMA_PREP_PQ_DISABLE_P) && src_cnt == 1) {
 		dma_addr_t single_source[2];
 		unsigned char single_source_coef[2];
 
@@ -761,6 +771,12 @@ ioat3_prep_pq_val(struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
 		  unsigned int src_cnt, const unsigned char *scf, size_t len,
 		  enum sum_check_flags *pqres, unsigned long flags)
 {
+	/* specify valid address for disabled result */
+	if (flags & DMA_PREP_PQ_DISABLE_P)
+		pq[0] = pq[1];
+	if (flags & DMA_PREP_PQ_DISABLE_Q)
+		pq[1] = pq[0];
+
 	/* the cleanup routine only sets bits on validate failure, it
 	 * does not clear bits on validate success... so clear it here
 	 */
@@ -778,9 +794,9 @@ ioat3_prep_pqxor(struct dma_chan *chan, dma_addr_t dst, dma_addr_t *src,
 	dma_addr_t pq[2];
 
 	memset(scf, 0, src_cnt);
-	flags |= DMA_PREP_PQ_DISABLE_Q;
 	pq[0] = dst;
-	pq[1] = ~0;
+	flags |= DMA_PREP_PQ_DISABLE_Q;
+	pq[1] = dst; /* specify valid address for disabled result */
 
 	return __ioat3_prep_pq_lock(chan, NULL, pq, src, src_cnt, scf, len,
 				    flags);
@@ -800,9 +816,9 @@ ioat3_prep_pqxor_val(struct dma_chan *chan, dma_addr_t *src,
 	*result = 0;
 
 	memset(scf, 0, src_cnt);
-	flags |= DMA_PREP_PQ_DISABLE_Q;
 	pq[0] = src[0];
-	pq[1] = ~0;
+	flags |= DMA_PREP_PQ_DISABLE_Q;
+	pq[1] = pq[0]; /* specify valid address for disabled result */
 
 	return __ioat3_prep_pq_lock(chan, result, pq, &src[1], src_cnt - 1, scf,
 				    len, flags);
@@ -1114,18 +1130,58 @@ static int __devinit ioat3_dma_self_test(struct ioatdma_device *device)
 	return 0;
 }
 
+static int ioat3_reset_hw(struct ioat_chan_common *chan)
+{
+	/* throw away whatever the channel was doing and get it
+	 * initialized, with ioat3 specific workarounds
+	 */
+	struct ioatdma_device *device = chan->device;
+	struct pci_dev *pdev = device->pdev;
+	u32 chanerr;
+	u16 dev_id;
+	int err;
+
+	ioat2_quiesce(chan, msecs_to_jiffies(100));
+
+	chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET);
+	writel(chanerr, chan->reg_base + IOAT_CHANERR_OFFSET);
+
+	/* -= IOAT ver.3 workarounds =- */
+	/* Write CHANERRMSK_INT with 3E07h to mask out the errors
+	 * that can cause stability issues for IOAT ver.3, and clear any
+	 * pending errors
+	 */
+	pci_write_config_dword(pdev, IOAT_PCI_CHANERRMASK_INT_OFFSET, 0x3e07);
+	err = pci_read_config_dword(pdev, IOAT_PCI_CHANERR_INT_OFFSET, &chanerr);
+	if (err) {
+		dev_err(&pdev->dev, "channel error register unreachable\n");
+		return err;
+	}
+	pci_write_config_dword(pdev, IOAT_PCI_CHANERR_INT_OFFSET, chanerr);
+
+	/* Clear DMAUNCERRSTS Cfg-Reg Parity Error status bit
+	 * (workaround for spurious config parity error after restart)
+	 */
+	pci_read_config_word(pdev, IOAT_PCI_DEVICE_ID_OFFSET, &dev_id);
+	if (dev_id == PCI_DEVICE_ID_INTEL_IOAT_TBG0)
+		pci_write_config_dword(pdev, IOAT_PCI_DMAUNCERRSTS_OFFSET, 0x10);
+
+	return ioat2_reset_sync(chan, msecs_to_jiffies(200));
+}
+
 int __devinit ioat3_dma_probe(struct ioatdma_device *device, int dca)
 {
 	struct pci_dev *pdev = device->pdev;
+	int dca_en = system_has_dca_enabled(pdev);
 	struct dma_device *dma;
 	struct dma_chan *c;
 	struct ioat_chan_common *chan;
 	bool is_raid_device = false;
 	int err;
-	u16 dev_id;
 	u32 cap;
 
 	device->enumerate_channels = ioat2_enumerate_channels;
+	device->reset_hw = ioat3_reset_hw;
 	device->self_test = ioat3_dma_self_test;
 	dma = &device->common;
 	dma->device_prep_dma_memcpy = ioat2_dma_prep_memcpy_lock;
@@ -1137,6 +1193,11 @@ int __devinit ioat3_dma_probe(struct ioatdma_device *device, int dca)
 	dma->device_prep_dma_interrupt = ioat3_prep_interrupt_lock;
 
 	cap = readl(device->reg_base + IOAT_DMA_CAP_OFFSET);
+
+	/* dca is incompatible with raid operations */
+	if (dca_en && (cap & (IOAT_CAP_XOR|IOAT_CAP_PQ)))
+		cap &= ~(IOAT_CAP_XOR|IOAT_CAP_PQ);
+
 	if (cap & IOAT_CAP_XOR) {
 		is_raid_device = true;
 		dma->max_xor = 8;
@@ -1186,18 +1247,15 @@ int __devinit ioat3_dma_probe(struct ioatdma_device *device, int dca)
 		device->timer_fn = ioat2_timer_event;
 	}
 
-	/* -= IOAT ver.3 workarounds =- */
-	/* Write CHANERRMSK_INT with 3E07h to mask out the errors
-	 * that can cause stability issues for IOAT ver.3
-	 */
-	pci_write_config_dword(pdev, IOAT_PCI_CHANERRMASK_INT_OFFSET, 0x3e07);
+	#ifdef CONFIG_ASYNC_TX_DISABLE_PQ_VAL_DMA
+	dma_cap_clear(DMA_PQ_VAL, dma->cap_mask);
+	dma->device_prep_dma_pq_val = NULL;
+	#endif
 
-	/* Clear DMAUNCERRSTS Cfg-Reg Parity Error status bit
-	 * (workaround for spurious config parity error after restart)
-	 */
-	pci_read_config_word(pdev, IOAT_PCI_DEVICE_ID_OFFSET, &dev_id);
-	if (dev_id == PCI_DEVICE_ID_INTEL_IOAT_TBG0)
-		pci_write_config_dword(pdev, IOAT_PCI_DMAUNCERRSTS_OFFSET, 0x10);
+	#ifdef CONFIG_ASYNC_TX_DISABLE_XOR_VAL_DMA
+	dma_cap_clear(DMA_XOR_VAL, dma->cap_mask);
+	dma->device_prep_dma_xor_val = NULL;
+	#endif
 
 	err = ioat_probe(device);
 	if (err)
diff --git a/drivers/dma/ioat/hw.h b/drivers/dma/ioat/hw.h
index 99afb12b..60e6754 100644
--- a/drivers/dma/ioat/hw.h
+++ b/drivers/dma/ioat/hw.h
@@ -39,6 +39,8 @@
 #define IOAT_VER_3_0            0x30    /* Version 3.0 */
 #define IOAT_VER_3_2            0x32    /* Version 3.2 */
 
+int system_has_dca_enabled(struct pci_dev *pdev);
+
 struct ioat_dma_descriptor {
 	uint32_t	size;
 	union {
diff --git a/drivers/dma/ioat/registers.h b/drivers/dma/ioat/registers.h
index 63038e1..e8ae63b 100644
--- a/drivers/dma/ioat/registers.h
+++ b/drivers/dma/ioat/registers.h
@@ -27,6 +27,7 @@
 
 #define IOAT_PCI_DEVICE_ID_OFFSET		0x02
 #define IOAT_PCI_DMAUNCERRSTS_OFFSET		0x148
+#define IOAT_PCI_CHANERR_INT_OFFSET		0x180
 #define IOAT_PCI_CHANERRMASK_INT_OFFSET		0x184
 
 /* MMIO Device Registers */
@@ -92,9 +93,7 @@
 #define IOAT_CHANCTRL_ERR_COMPLETION_EN		0x0004
 #define IOAT_CHANCTRL_INT_REARM			0x0001
 #define IOAT_CHANCTRL_RUN			(IOAT_CHANCTRL_INT_REARM |\
-						 IOAT_CHANCTRL_ERR_COMPLETION_EN |\
-						 IOAT_CHANCTRL_ANY_ERR_ABORT_EN |\
-						 IOAT_CHANCTRL_ERR_INT_EN)
+						 IOAT_CHANCTRL_ANY_ERR_ABORT_EN)
 
 #define IOAT_DMA_COMP_OFFSET			0x02	/* 16-bit DMA channel compatibility */
 #define IOAT_DMA_COMP_V1			0x0001	/* Compatibility with DMA version 1 */
diff --git a/drivers/dma/shdma.c b/drivers/dma/shdma.c
index 9546f5f..d10cc89 100644
--- a/drivers/dma/shdma.c
+++ b/drivers/dma/shdma.c
@@ -730,17 +730,16 @@ static int __init sh_dmae_probe(struct platform_device *pdev)
 #endif
 	struct sh_dmae_device *shdev;
 
+	/* get platform data */
+	if (!pdev->dev.platform_data)
+		return -ENODEV;
+
 	shdev = kzalloc(sizeof(struct sh_dmae_device), GFP_KERNEL);
 	if (!shdev) {
 		dev_err(&pdev->dev, "No enough memory\n");
-		err = -ENOMEM;
-		goto shdev_err;
+		return -ENOMEM;
 	}
 
-	/* get platform data */
-	if (!pdev->dev.platform_data)
-		goto shdev_err;
-
 	/* platform data */
 	memcpy(&shdev->pdata, pdev->dev.platform_data,
 			sizeof(struct sh_dmae_pdata));
@@ -814,7 +813,6 @@ eirq_err:
 rst_err:
 	kfree(shdev);
 
-shdev_err:
 	return err;
 }