PCI DMA_MR Problem

3 messages, 2 authors, 2006-08-14 · open the first message on its own page

PCI DMA_MR Problem

From: jimmy liu <hidden>
Date: 2006-08-11 13:57:48

I got a problem when I set the pci dmamr for MPC8250
for DMA PCI transfering data on linux kernel 2.6.17.
When I set the values for the pci_dmamr registers,
then print the register values back, some bits can not
be set. Did anybody know what are the problem, or I
have to set other stuff.

Thanks.

The code like this:

volatile cpm2_map_t *immap = cpm2_immr;
immap->im_pci.pci_dmamr0 = 0x0042b00c;
immap->im_pci.pci_dmamr1 = 0x0042b00c;
immap->im_pci.pci_dmamr2 = 0x0042b00c;
immap->im_pci.pci_dmamr3 = 0x0042b00c;

printk("DMA0 MR = 0x%08x\n",
immap->im_pci.pci_dmamr0);
printk("DMA1 MR (0x%08x) = 0x%08x\n",
immap->im_pci.pci_dmamr1);
printk("DMA2 MR (0x%08x) = 0x%08x\n",
immap->im_pci.pci_dmamr2);
printk("DMA3 MR (0x%08x) = 0x%08x\n",
immap->im_pci.pci_dmamr3);

The results are following:
DMA0 MR (0xf0010500) = 0x0040b000
DMA1 MR (0xf0010580) = 0x0040b000
DMA2 MR (0xf0010600) = 0x0040b000
DMA3 MR (0xf0010680) = 0x0040b000



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RE: PCI DMA_MR Problem

From: Liu Dave-r63238 <hidden>
Date: 2006-08-14 03:53:11

The memory map configuration registers is little-endain. Be careful this
Please byte swap this
-Dave=20
=20
I got a problem when I set the pci dmamr for MPC8250 for DMA=20
PCI transfering data on linux kernel 2.6.17.
When I set the values for the pci_dmamr registers, then print=20
the register values back, some bits can not be set. Did=20
anybody know what are the problem, or I have to set other stuff.
=20
Thanks.
=20
The code like this:
=20
volatile cpm2_map_t *immap =3D cpm2_immr;
immap->im_pci.pci_dmamr0 =3D 0x0042b00c;
immap->im_pci.pci_dmamr1 =3D 0x0042b00c;
immap->im_pci.pci_dmamr2 =3D 0x0042b00c;
immap->im_pci.pci_dmamr3 =3D 0x0042b00c;
=20
printk("DMA0 MR =3D 0x%08x\n",
immap->im_pci.pci_dmamr0);
printk("DMA1 MR (0x%08x) =3D 0x%08x\n",
immap->im_pci.pci_dmamr1);
printk("DMA2 MR (0x%08x) =3D 0x%08x\n",
immap->im_pci.pci_dmamr2);
printk("DMA3 MR (0x%08x) =3D 0x%08x\n",
immap->im_pci.pci_dmamr3);
=20
The results are following:
DMA0 MR (0xf0010500) =3D 0x0040b000
DMA1 MR (0xf0010580) =3D 0x0040b000
DMA2 MR (0xf0010600) =3D 0x0040b000
DMA3 MR (0xf0010680) =3D 0x0040b000
=20
=20
=20
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around http://mail.yahoo.com=20
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=20

RE: PCI DMA_MR Problem

From: jimmy liu <hidden>
Date: 2006-08-14 12:38:33

I see.

Thanks.

Jimmy
--- Liu Dave-r63238 <DaveLiu@freescale.com> wrote:
The memory map configuration registers is
little-endain. Be careful this
Please byte swap this
-Dave 
quoted
I got a problem when I set the pci dmamr for
MPC8250 for DMA 
quoted
PCI transfering data on linux kernel 2.6.17.
When I set the values for the pci_dmamr registers,
then print 
quoted
the register values back, some bits can not be
set. Did 
quoted
anybody know what are the problem, or I have to
set other stuff.
quoted
Thanks.

The code like this:

volatile cpm2_map_t *immap = cpm2_immr;
immap->im_pci.pci_dmamr0 = 0x0042b00c;
immap->im_pci.pci_dmamr1 = 0x0042b00c;
immap->im_pci.pci_dmamr2 = 0x0042b00c;
immap->im_pci.pci_dmamr3 = 0x0042b00c;

printk("DMA0 MR = 0x%08x\n",
immap->im_pci.pci_dmamr0);
printk("DMA1 MR (0x%08x) = 0x%08x\n",
immap->im_pci.pci_dmamr1);
printk("DMA2 MR (0x%08x) = 0x%08x\n",
immap->im_pci.pci_dmamr2);
printk("DMA3 MR (0x%08x) = 0x%08x\n",
immap->im_pci.pci_dmamr3);

The results are following:
DMA0 MR (0xf0010500) = 0x0040b000
DMA1 MR (0xf0010580) = 0x0040b000
DMA2 MR (0xf0010600) = 0x0040b000
DMA3 MR (0xf0010680) = 0x0040b000



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around http://mail.yahoo.com 
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quoted

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