Hi Vladimir,
Thanks for the feedback;
Marek, Vladimir,
there is a question below; I will wait for feedback before sending an updated version of the patch.
Sylvain
-----Original Message----- From: Vladimir Zapolskiy [mailto:vz@mleia.com]
Hi Sylvain,
On 05.08.2015 21:31, slemieux.tyco@gmail.com wrote:
From: Sylvain Lemieux slemieux@tycoint.com
Incorporate DMA driver from legacy LPCLinux NXP BSP. The files taken from the legacy patch are:
- lpc32xx DMA driver
- lpc3250 header file DMA registers definition.
The legacy driver was updated and clean-up as part of the integration with the latest u-boot.
Signed-off-by: Sylvain Lemieux slemieux@tycoint.com
[...]
diff --git a/arch/arm/include/asm/arch-lpc32xx/dma.h b/arch/arm/include/asm/arch-lpc32xx/dma.h new file mode 100644 index 0000000..15d829c --- /dev/null +++ b/arch/arm/include/asm/arch-lpc32xx/dma.h @@ -0,0 +1,37 @@ +/*
- LPC32xx DMA Controller Interface
[...]
+int lpc32xx_dma_get_channel(void); +int lpc32xx_dma_start_xfer(int channel, const struct lpc32xx_dmac_ll *desc,
u32 config);+int lpc32xx_dma_wait_status(int channel); +void lpc32xx_dma_put_channel(int channel);
There is no users of lpc32xx_dma_put_channel() interface, do you have them in mind?
The legacy NXP BSP driver was providing the support the get and release a channel; I kept it there, knowing is currently not used.
Do we want to keep this feature or remove it and only allowed channel allocation only?
[...]
+++ b/drivers/dma/lpc32xx_dma.c @@ -0,0 +1,163 @@ +/*
[...]
+int lpc32xx_dma_start_xfer(int channel, const struct lpc32xx_dmac_ll *desc,
u32 config)+{
- if (unlikely((BIT_MASK(channel) & alloc_ch) == 0)) {
Would it be possible to change "int channel" to some unsigned type?
If the intention is to reserve (channel < 0) for potentially invalid/unallocated channel, as it is done in NAND SLC, please add a check for this case here.
This was the legacy NXP BSP original behavior.
I will change the channel to "unsigned int" for the transfer API; the reserve API will continue to be return the channel as "int", to allowed validation; the NAND SLC will keep the channel number as an "unsigned int".
printf("ERR: Request for xfer on unallocated channel %d\r\n",
[...]
channel);BUG();The function returns int type, but in fact it returns only 0, either this function return type can be changed to void, or IMO better to return error here instead of fatal BUG() and add a check on client side.
I will modify it to return -1 on error and check on client side; The client side will generate the fatal BUG().
[...]
-- With best wishes, Vladimir
________________________________
This e-mail contains privileged and confidential information intended for the use of the addressees named above. If you are not the intended recipient of this e-mail, you are hereby notified that you must not disseminate, copy or take any action in respect of any information contained in it. If you have received this e-mail in error, please notify the sender immediately by e-mail and immediately destroy this e-mail and its attachments.