Re: [PATCH 2/2] soc: qcom: Add Shared Memory Manager driver

[Andy Gross <agross@codeaurora.org>]

On Fri, Apr 03, 2015 at 04:03:20PM -0700, Bjorn Andersson wrote:
<snip>

> +static int qcom_smem_alloc_private(struct qcom_smem *smem,
> +				   unsigned host,
> +				   unsigned item,
> +				   size_t size)
> +{

<snip>

> +	alloc_size = sizeof(*hdr) + ALIGN(size, 8);
> +	if (p + alloc_size >= (void *)phdr + phdr->offset_free_uncached) {
> +		dev_err(smem->dev, "Out of memory\n");
> +		return -ENOSPC;
> +	}

This check always fails due to the fact that we always get a ptr that points to
something beyond the free_uncached area.  We ought to use:
alloc_size > phdr->offset_free_cached - phdr->offset_free_uncached

> +
> +	hdr = p;
> +	hdr->canary = SMEM_PRIVATE_CANARY;
> +	hdr->item = item;
> +	hdr->size = ALIGN(size, 8);
> +	hdr->padding_data = hdr->size - size;
> +	hdr->padding_hdr = 0;
> +

<snip>

> +static int qcom_smem_probe(struct platform_device *pdev)
> +{

<snip>

> +	ret = of_address_to_resource(np, 0, &r);
> +	of_node_put(np);
> +	if (ret)
> +		return ret;
> +
> +	smem->regions[0].aux_base = (u32)r.start;
> +	smem->regions[0].size = resource_size(&r);
> +	smem->regions[0].virt_base = devm_ioremap(&pdev->dev,
> +						  r.start,
> +						  resource_size(&r));

Need to use devm_ioremap_nocache() instead.  We need uncached accesses.

> +	if (!smem->regions[0].virt_base)
> +		return -ENOMEM;
> +
> +	for (i = 1; i < num_regions; i++) {
> +		res = platform_get_resource(pdev, IORESOURCE_MEM, i - 1);
> +
> +		smem->regions[i].aux_base = (u32)res->start;
> +		smem->regions[i].size = resource_size(res);
> +		smem->regions[i].virt_base = devm_ioremap(&pdev->dev,
> +							  res->start,
> +							  resource_size(res));

Same thing here.

> +		if (!smem->regions[i].virt_base)
> +			return -ENOMEM;
> +	}
> +

<snip>

> diff --git a/include/linux/soc/qcom/smem.h b/include/linux/soc/qcom/smem.h
> new file mode 100644
> index 0000000..294070de
> --- /dev/null
> +++ b/include/linux/soc/qcom/smem.h
> @@ -0,0 +1,14 @@
> +#ifndef __QCOM_SMEM_H__
> +#define __QCOM_SMEM_H__
> +
> +struct device_node;
> +struct qcom_smem;
> +
> +#define QCOM_SMEM_HOST_ANY -1

Would it make sense to throw in the remote processor enumeration?  Same with the
fixed/dynamic item list?

> +
> +int qcom_smem_alloc(unsigned host, unsigned item, size_t size);
> +int qcom_smem_get(unsigned host, unsigned item, void **ptr, size_t *size);
> +
> +int qcom_smem_get_free_space(unsigned host);


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