Re: [PATCH V10 03/12] of: dma: Move range size workaround to of_dma_get_range()
From: Robin Murphy
Date: Thu Apr 06 2017 - 06:03:29 EST
Hi Frank,
On 06/04/17 07:24, Frank Rowand wrote:
> On 04/04/17 03:18, Sricharan R wrote:
>> From: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
>>
>> Invalid dma-ranges values should be worked around when retrieving the
>> DMA range in of_dma_get_range(), not by all callers of the function.
>> This isn't much of a problem now that we have a single caller, but that
>> situation will change when moving DMA configuration to device probe
>> time.
>
> Please drop this patch from the series. I just now sent Rob an
> alternative that reflects other changes that have occurred since
> this patch series was first created many, many moons ago
> (https://lkml.org/lkml/2017/4/6/53).
Fine by me too - if we can get rid of that dubious fixup altogether, all
the better. Feel free to transfer my Reviewed-by to your patch if you like.
Thanks,
Robin.
> Thanks,
>
> Frank
>
>>
>> Tested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
>> Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
>> ---
>> drivers/of/address.c | 20 ++++++++++++++++++--
>> drivers/of/device.c | 15 ---------------
>> 2 files changed, 18 insertions(+), 17 deletions(-)
>>
>> diff --git a/drivers/of/address.c b/drivers/of/address.c
>> index 02b2903..6aeb816 100644
>> --- a/drivers/of/address.c
>> +++ b/drivers/of/address.c
>> @@ -819,8 +819,8 @@ void __iomem *of_io_request_and_map(struct device_node *np, int index,
>> * CPU addr (phys_addr_t) : pna cells
>> * size : nsize cells
>> *
>> - * It returns -ENODEV if "dma-ranges" property was not found
>> - * for this device in DT.
>> + * Return 0 on success, -ENODEV if the "dma-ranges" property was not found for
>> + * this device in DT, or -EINVAL if the CPU address or size is invalid.
>> */
>> int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *size)
>> {
>> @@ -880,6 +880,22 @@ int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *siz
>> *dma_addr = dmaaddr;
>>
>> *size = of_read_number(ranges + naddr + pna, nsize);
>> + /*
>> + * DT nodes sometimes incorrectly set the size as a mask. Work around
>> + * those incorrect DT by computing the size as mask + 1.
>> + */
>> + if (*size & 1) {
>> + pr_warn("%s: size 0x%llx for dma-range in node(%s) set as mask\n",
>> + __func__, *size, np->full_name);
>> + *size = *size + 1;
>> + }
>> +
>> + if (!*size) {
>> + pr_err("%s: invalid size zero for dma-range in node(%s)\n",
>> + __func__, np->full_name);
>> + ret = -EINVAL;
>> + goto out;
>> + }
>>
>> pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n",
>> *dma_addr, *paddr, *size);
>> diff --git a/drivers/of/device.c b/drivers/of/device.c
>> index b1e6beb..09dedd0 100644
>> --- a/drivers/of/device.c
>> +++ b/drivers/of/device.c
>> @@ -110,21 +110,6 @@ void of_dma_configure(struct device *dev, struct device_node *np)
>> size = dev->coherent_dma_mask + 1;
>> } else {
>> offset = PFN_DOWN(paddr - dma_addr);
>> -
>> - /*
>> - * Add a work around to treat the size as mask + 1 in case
>> - * it is defined in DT as a mask.
>> - */
>> - if (size & 1) {
>> - dev_warn(dev, "Invalid size 0x%llx for dma-range\n",
>> - size);
>> - size = size + 1;
>> - }
>> -
>> - if (!size) {
>> - dev_err(dev, "Adjusted size 0x%llx invalid\n", size);
>> - return;
>> - }
>> dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset);
>> }
>>
>>