Thread (14 messages) 14 messages, 3 authors, 2015-01-28

[PATCH v5 3/8] of: fix size when dma-range is not used

From: Murali Karicheri <hidden>
Date: 2015-01-28 20:42:00
Also in: linux-devicetree, linux-iommu, linux-pci, lkml

On 01/28/2015 06:21 AM, Robin Murphy wrote:
Hi Murali,

[sorry, missed replying to yesterday's version]

On 27/01/15 21:00, Murali Karicheri wrote:
quoted
Fix the dma-range size when the DT attribute is missing. i.e set size to
dev->coherent_dma_mask + 1 instead of dev->coherent_dma_mask. Also add
code to check invalid values of size configured in DT and log error.

Cc: Joerg Roedel <joro@8bytes.org>
Cc: Grant Likely <redacted>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Will Deacon <redacted>
Cc: Russell King <redacted>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>

Signed-off-by: Murali Karicheri <redacted>
---
drivers/of/device.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/drivers/of/device.c b/drivers/of/device.c
index 2de320d..17504f4 100644
--- a/drivers/of/device.c
+++ b/drivers/of/device.c
@@ -105,12 +105,19 @@ void of_dma_configure(struct device *dev, struct
device_node *np)
ret = of_dma_get_range(np, &dma_addr, &paddr, &size);
if (ret < 0) {
dma_addr = offset = 0;
- size = dev->coherent_dma_mask;
+ size = dev->coherent_dma_mask + 1;
} else {
offset = PFN_DOWN(paddr - dma_addr);
dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset);
}

+ if (is_power_of_2(size + 1))
+ size = size + 1;
+ else if (!is_power_of_2(size)) {
+ dev_err(dev, "invalid size\n");
+ return;
+ }
+
Couldn't these checks go into the "else" path above? We don't need to
check the non-DT case, because we know we've just set it to something
sensible.
Robin,

Sure it can. I was doing flip/flop on the choice and thought it doesn' 
matter either way. Please also repond to Catalin's comment if you have 
any issues so that I can avoid additional spin on this patch.

Thanks

Murali
Robin.
quoted
dev->dma_pfn_offset = offset;

coherent = of_dma_is_coherent(np);

-- 
Murali Karicheri
Linux Kernel, Texas Instruments
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