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powerpc: Add DMA mask to MPSC serial and network and UART device to serial

PATCH In review Corey Minyard 2 participants 5 messages Jan 30, 2010 – Feb 2, 2010

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Corey Minyard

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#0 lore raw

PATCH 1/1 powerpc: Add DMA mask to MPSC serial and network and UART device to serial

From: Corey Minyard <[email protected]>

The MPSC drivers that use DMA need to set coherent_dma_mask to allow dma_alloc_xxx routines to work properly. Also, the mpsc serial driver needed to set pi->port.dev to register properly. With these fixes, the MPSC drivers seem to work again.

Signed-off-by Corey Minyard <[email protected]>

---
I'm not really sure about where to set the coherent_dma_mask, it seems like a more general place would be better but I couldn't find it.

Without these, the console stops working after the switchover and the network driver fails to allocate buffers. With these, my board boots up and works fine.

drivers/serial/mpsc.c +3 -0
Index: linux-2.6.31/drivers/serial/mpsc.c
===================================================================
@@ -2071,6 +2071,9 @@ static int mpsc_drv_probe(struct platfor
 		if (!(rc = mpsc_drv_map_regs(pi, dev))) {
 			mpsc_drv_get_platform_data(pi, dev, dev->id);
 
+			dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
+			pi->port.dev = &dev->dev;
+
 			if (!(rc = mpsc_make_ready(pi))) {
 				spin_lock_init(&pi->tx_lock);
 				if (!(rc = uart_add_one_port(&mpsc_reg,
drivers/net/mv643xx_eth.c +1 -1
Index: linux-2.6.31/drivers/net/mv643xx_eth.c
===================================================================
@@ -2916,7 +2916,7 @@ static int mv643xx_eth_probe(struct plat
 	mp->shared = platform_get_drvdata(pd->shared);
 	mp->base = mp->shared->base + 0x0400 + (pd->port_number << 10);
 	mp->port_num = pd->port_number;
-
+	pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
 	mp->dev = dev;
 
 	set_params(mp, pd);
#1 lore raw
Quoted 9 lines · Corey Minyard

From: Corey Minyard <[email protected]>

The MPSC drivers that use DMA need to set coherent_dma_mask to allow dma_alloc_xxx routines to work properly. Also, the mpsc serial driver needed to set pi->port.dev to register properly. With these fixes, the MPSC drivers seem to work again.

Signed-off-by Corey Minyard <[email protected]>

---

Is that enough ? Since 2.6.31 we also need the dma ops to be filled properly and obviously that isn't going to happen for random platform devices... Or are those initialized elsewhere by your platform code ? In which case it might be a good place to also set the coherent mask...

Maybe we should have a more generic way to set the "default" dma information (including ops, masks etc...) for use by platform, of_platform etc... devices.

Cheers,
Ben.

Quoted 38 lines

I'm not really sure about where to set the coherent_dma_mask, it seems like a more general place would be better but I couldn't find it.

Without these, the console stops working after the switchover and the network driver fails to allocate buffers. With these, my board boots up and works fine.

Index: linux-2.6.31/drivers/serial/mpsc.c
===================================================================

drivers/serial/mpsc.c +3 -0
@@ -2071,6 +2071,9 @@ static int mpsc_drv_probe(struct platfor
 		if (!(rc = mpsc_drv_map_regs(pi, dev))) {
 			mpsc_drv_get_platform_data(pi, dev, dev->id);
 
+			dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
+			pi->port.dev = &dev->dev;
+
 			if (!(rc = mpsc_make_ready(pi))) {
 				spin_lock_init(&pi->tx_lock);
 				if (!(rc = uart_add_one_port(&mpsc_reg,

Index: linux-2.6.31/drivers/net/mv643xx_eth.c
===================================================================

drivers/net/mv643xx_eth.c +1 -1
@@ -2916,7 +2916,7 @@ static int mv643xx_eth_probe(struct plat
 	mp->shared = platform_get_drvdata(pd->shared);
 	mp->base = mp->shared->base + 0x0400 + (pd->port_number << 10);
 	mp->port_num = pd->port_number;
-
+	pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
 	mp->dev = dev;
 
 	set_params(mp, pd);

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author
#2 lore raw
Quoted 9 lines · Benjamin Herrenschmidt
Quoted 7 lines · Corey Minyard

From: Corey Minyard <[email protected]>

The MPSC drivers that use DMA need to set coherent_dma_mask to allow dma_alloc_xxx routines to work properly. Also, the mpsc serial driver needed to set pi->port.dev to register properly. With these fixes, the MPSC drivers seem to work again.

Quoted 9 lines
Quoted 3 lines
Signed-off-by Corey Minyard <[email protected]>

---

Is that enough ? Since 2.6.31 we also need the dma ops to be filled properly and obviously that isn't going to happen for random platform devices... Or are those initialized elsewhere by your platform code ? In which case it might be a good place to also set the coherent mask...

That's done in ppc_dflt_bus_notify(), but that didn't seem an appropriate place to do this. If it is, it's easy enough to add it there, but that would mean it would get set for all devices on any type of ppc system.

-corey

Quoted 50 lines

Maybe we should have a more generic way to set the "default" dma information (including ops, masks etc...) for use by platform, of_platform etc... devices.

Cheers,
Ben.

Quoted 39 lines

I'm not really sure about where to set the coherent_dma_mask, it seems like a more general place would be better but I couldn't find it.

Without these, the console stops working after the switchover andantipode the network driver fails to allocate buffers. With these, my board boots up and works fine.

Index: linux-2.6.31/drivers/serial/mpsc.c
===================================================================

drivers/serial/mpsc.c +3 -0
@@ -2071,6 +2071,9 @@ static int mpsc_drv_probe(struct platfor
 		if (!(rc = mpsc_drv_map_regs(pi, dev))) {
 			mpsc_drv_get_platform_data(pi, dev, dev->id);
 
+			dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
+			pi->port.dev = &dev->dev;
+
 			if (!(rc = mpsc_make_ready(pi))) {
 				spin_lock_init(&pi->tx_lock);
 				if (!(rc = uart_add_one_port(&mpsc_reg,

Index: linux-2.6.31/drivers/net/mv643xx_eth.c
===================================================================

drivers/net/mv643xx_eth.c +1 -1
@@ -2916,7 +2916,7 @@ static int mv643xx_eth_probe(struct plat
 	mp->shared = platform_get_drvdata(pd->shared);
 	mp->base = mp->shared->base + 0x0400 + (pd->port_number << 10);
 	mp->port_num = pd->port_number;
-
+	pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
 	mp->dev = dev;
 
 	set_params(mp, pd);

_______________________________________________
Linuxppc-dev mailing list
[email protected]
https://lists.ozlabs.org/listinfo/linuxppc-dev

#3 lore raw
Quoted 5 lines · Corey Minyard

That's done in ppc_dflt_bus_notify(), but that didn't seem an appropriate
place to do this. If it is, it's easy enough to add it there, but that would mean it would get set for all devices on any type of ppc system.

Well, we are looking at setting up a sane default here. It can always be overriden if necessary.

Cheers,
Ben.

author
#4 lore raw

PATCH 1/1 powerpc: Add coherent_dma_mask setting to platform devices

In reply to Benjamin Herrenschmidt

From: Corey Minyard <[email protected]>

DMA ops requires that coherent_dma_mask be set properly for a device, but this was not being done for platform devices on powerpc. The MPSC drivers, in particular, need this for both serial and ethernet or they won't be able to allocate memory.

Signed-off-by Corey Minyard <[email protected]>

---
How about this patch? It seems to work ok and I suppose this makes sense. I'll send the uart setting in another patch.

arch/powerpc/kernel/setup-common.c +1 -0
Index: linux-2.6/arch/powerpc/kernel/setup-common.c
===================================================================
@@ -681,6 +681,7 @@ static int ppc_dflt_bus_notify(struct no
 		return 0;
 
 	set_dma_ops(dev, &dma_direct_ops);
+	pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
 
 	return NOTIFY_DONE;
 }