[PATCH v5 3/8] of: fix size when dma-range is not used
From: Rob Herring <hidden>
Date: 2015-01-28 02:37:38
Also in:
linux-devicetree, linux-iommu, linux-pci, lkml
On Tue, Jan 27, 2015 at 3:00 PM, Murali Karicheri [off-list ref] wrote:
quoted hunk ↗ jump to hunk
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;
This is fine since coherent_dma_mask will always be 4G - 1 in this case.
} 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;I think this is too restrictive. I think checking bit 0 is 1 is enough to tell the size is a mask. I would like it to be a WARN if detected and just add 1. Rob