Re: [PATCH v3] remoteproc: qcom: Use of_reserved_mem_lookup()

[Caleb Connolly]

On 10/07/2023 21:34, Stephan Gerhold wrote:
> Reserved memory can be either looked up using the generic function
> of_address_to_resource() or using the special of_reserved_mem_lookup().
> The latter has the advantage that it ensures that the referenced memory
> region was really reserved and is not e.g. status = "disabled".
> 
> of_reserved_mem also supports allocating reserved memory dynamically at
> boot time. This works only when using of_reserved_mem_lookup() since
> there won't be a fixed address in the device tree.
> 
> Switch the code to use of_reserved_mem_lookup(), similar to
> qcom_q6v5_wcss.c which is using it already. There is no functional
> difference for static reserved memory allocations.
> 
> While at it this also adds two missing of_node_put() calls in
> qcom_q6v5_pas.c.
> 
> Signed-off-by: Stephan Gerhold <stephan@xxxxxxxxxxx>

Tested-by: Caleb Connolly <caleb.connolly@xxxxxxxxxx> # SDM845
Reviewed-by: Caleb Connolly <caleb.connolly@xxxxxxxxxx>
> ---
> Changes in v3:
> - Revert additional rmem->size checks: None of the existing users of
>   of_reserved_mem_lookup() have it so it sounds better to handle this 
>   internally in of_reserved_mem. I'll work on a separate patch series
>   to improve this independently of this one. (Caleb)
> - Link to v2: https://lore.kernel.org/r/20230529-rproc-of-rmem-v2-0-95e39b959585@xxxxxxxxxxx
> 
> Changes in v2:
> - Add missing check for rmem (Bjorn)
> - Add checks for rmem->size to ensure dynamic reserved memory was 
>   really allocated
> - Link to v1: https://lore.kernel.org/r/20230529-rproc-of-rmem-v1-1-5b1e38880aba@xxxxxxxxxxx
> ---
> See e.g. [1] for an example of dynamically allocated reserved memory.
> (This patch does *not* depend on [1] and is useful without as well...)
> 
> NOTE: Changes in qcom_q6v5_adsp.c and qcom_q6v5_pas.c are untested,
> I only checked qcom_q6v5_mss.c and qcom_wcnss.c on MSM8916/DB410c.
> The code changes are pretty similar for all of those though.
> 
> [1]: https://lore.kernel.org/linux-arm-msm/20230510-dt-resv-bottom-up-v1-5-3bf68873dbed@xxxxxxxxxxx/
> ---
>  drivers/remoteproc/qcom_q6v5_adsp.c | 24 ++++++++---------
>  drivers/remoteproc/qcom_q6v5_mss.c  | 33 ++++++++++++++----------
>  drivers/remoteproc/qcom_q6v5_pas.c  | 51 ++++++++++++++++++++-----------------
>  drivers/remoteproc/qcom_wcnss.c     | 24 ++++++++---------
>  4 files changed, 69 insertions(+), 63 deletions(-)
> 
> diff --git a/drivers/remoteproc/qcom_q6v5_adsp.c b/drivers/remoteproc/qcom_q6v5_adsp.c
> index 6777a3bd6226..d3caaa551916 100644
> --- a/drivers/remoteproc/qcom_q6v5_adsp.c
> +++ b/drivers/remoteproc/qcom_q6v5_adsp.c
> @@ -14,8 +14,8 @@
>  #include <linux/kernel.h>
>  #include <linux/mfd/syscon.h>
>  #include <linux/module.h>
> -#include <linux/of_address.h>
>  #include <linux/of_device.h>
> +#include <linux/of_reserved_mem.h>
>  #include <linux/platform_device.h>
>  #include <linux/pm_domain.h>
>  #include <linux/pm_runtime.h>
> @@ -637,28 +637,26 @@ static int adsp_init_mmio(struct qcom_adsp *adsp,
>  
>  static int adsp_alloc_memory_region(struct qcom_adsp *adsp)
>  {
> +	struct reserved_mem *rmem = NULL;
>  	struct device_node *node;
> -	struct resource r;
> -	int ret;
>  
>  	node = of_parse_phandle(adsp->dev->of_node, "memory-region", 0);
> -	if (!node) {
> -		dev_err(adsp->dev, "no memory-region specified\n");
> +	if (node)
> +		rmem = of_reserved_mem_lookup(node);
> +	of_node_put(node);
> +
> +	if (!rmem) {
> +		dev_err(adsp->dev, "unable to resolve memory-region\n");
>  		return -EINVAL;
>  	}
>  
> -	ret = of_address_to_resource(node, 0, &r);
> -	of_node_put(node);
> -	if (ret)
> -		return ret;
> -
> -	adsp->mem_phys = adsp->mem_reloc = r.start;
> -	adsp->mem_size = resource_size(&r);
> +	adsp->mem_phys = adsp->mem_reloc = rmem->base;
> +	adsp->mem_size = rmem->size;
>  	adsp->mem_region = devm_ioremap_wc(adsp->dev,
>  				adsp->mem_phys, adsp->mem_size);
>  	if (!adsp->mem_region) {
>  		dev_err(adsp->dev, "unable to map memory region: %pa+%zx\n",
> -			&r.start, adsp->mem_size);
> +			&rmem->base, adsp->mem_size);
>  		return -EBUSY;
>  	}
>  
> diff --git a/drivers/remoteproc/qcom_q6v5_mss.c b/drivers/remoteproc/qcom_q6v5_mss.c
> index 70bffc9f33f6..69b90dc32d8a 100644
> --- a/drivers/remoteproc/qcom_q6v5_mss.c
> +++ b/drivers/remoteproc/qcom_q6v5_mss.c
> @@ -15,7 +15,6 @@
>  #include <linux/kernel.h>
>  #include <linux/mfd/syscon.h>
>  #include <linux/module.h>
> -#include <linux/of_address.h>
>  #include <linux/of_device.h>
>  #include <linux/of_reserved_mem.h>
>  #include <linux/platform_device.h>
> @@ -1875,8 +1874,6 @@ static int q6v5_alloc_memory_region(struct q6v5 *qproc)
>  	struct device_node *child;
>  	struct reserved_mem *rmem;
>  	struct device_node *node;
> -	struct resource r;
> -	int ret;
>  
>  	/*
>  	 * In the absence of mba/mpss sub-child, extract the mba and mpss
> @@ -1891,15 +1888,20 @@ static int q6v5_alloc_memory_region(struct q6v5 *qproc)
>  		of_node_put(child);
>  	}
>  
> -	ret = of_address_to_resource(node, 0, &r);
> +	if (!node) {
> +		dev_err(qproc->dev, "no mba memory-region specified\n");
> +		return -EINVAL;
> +	}
> +
> +	rmem = of_reserved_mem_lookup(node);
>  	of_node_put(node);
> -	if (ret) {
> +	if (!rmem) {
>  		dev_err(qproc->dev, "unable to resolve mba region\n");
> -		return ret;
> +		return -EINVAL;
>  	}
>  
> -	qproc->mba_phys = r.start;
> -	qproc->mba_size = resource_size(&r);
> +	qproc->mba_phys = rmem->base;
> +	qproc->mba_size = rmem->size;
>  
>  	if (!child) {
>  		node = of_parse_phandle(qproc->dev->of_node,
> @@ -1910,15 +1912,20 @@ static int q6v5_alloc_memory_region(struct q6v5 *qproc)
>  		of_node_put(child);
>  	}
>  
> -	ret = of_address_to_resource(node, 0, &r);
> +	if (!node) {
> +		dev_err(qproc->dev, "no mpss memory-region specified\n");
> +		return -EINVAL;
> +	}
> +
> +	rmem = of_reserved_mem_lookup(node);
>  	of_node_put(node);
> -	if (ret) {
> +	if (!rmem) {
>  		dev_err(qproc->dev, "unable to resolve mpss region\n");
> -		return ret;
> +		return -EINVAL;
>  	}
>  
> -	qproc->mpss_phys = qproc->mpss_reloc = r.start;
> -	qproc->mpss_size = resource_size(&r);
> +	qproc->mpss_phys = qproc->mpss_reloc = rmem->base;
> +	qproc->mpss_size = rmem->size;
>  
>  	if (!child) {
>  		node = of_parse_phandle(qproc->dev->of_node, "memory-region", 2);
> diff --git a/drivers/remoteproc/qcom_q6v5_pas.c b/drivers/remoteproc/qcom_q6v5_pas.c
> index 3153d82037e7..58f8b81f6d52 100644
> --- a/drivers/remoteproc/qcom_q6v5_pas.c
> +++ b/drivers/remoteproc/qcom_q6v5_pas.c
> @@ -13,8 +13,8 @@
>  #include <linux/interrupt.h>
>  #include <linux/kernel.h>
>  #include <linux/module.h>
> -#include <linux/of_address.h>
>  #include <linux/of_device.h>
> +#include <linux/of_reserved_mem.h>
>  #include <linux/platform_device.h>
>  #include <linux/pm_domain.h>
>  #include <linux/pm_runtime.h>
> @@ -533,9 +533,8 @@ static void adsp_pds_detach(struct qcom_adsp *adsp, struct device **pds,
>  
>  static int adsp_alloc_memory_region(struct qcom_adsp *adsp)
>  {
> +	struct reserved_mem *rmem;
>  	struct device_node *node;
> -	struct resource r;
> -	int ret;
>  
>  	node = of_parse_phandle(adsp->dev->of_node, "memory-region", 0);
>  	if (!node) {
> @@ -543,17 +542,19 @@ static int adsp_alloc_memory_region(struct qcom_adsp *adsp)
>  		return -EINVAL;
>  	}
>  
> -	ret = of_address_to_resource(node, 0, &r);
> +	rmem = of_reserved_mem_lookup(node);
>  	of_node_put(node);
> -	if (ret)
> -		return ret;
> +	if (!rmem) {
> +		dev_err(adsp->dev, "unable to resolve memory-region\n");
> +		return -EINVAL;
> +	}
>  
> -	adsp->mem_phys = adsp->mem_reloc = r.start;
> -	adsp->mem_size = resource_size(&r);
> +	adsp->mem_phys = adsp->mem_reloc = rmem->base;
> +	adsp->mem_size = rmem->size;
>  	adsp->mem_region = devm_ioremap_wc(adsp->dev, adsp->mem_phys, adsp->mem_size);
>  	if (!adsp->mem_region) {
>  		dev_err(adsp->dev, "unable to map memory region: %pa+%zx\n",
> -			&r.start, adsp->mem_size);
> +			&rmem->base, adsp->mem_size);
>  		return -EBUSY;
>  	}
>  
> @@ -566,16 +567,19 @@ static int adsp_alloc_memory_region(struct qcom_adsp *adsp)
>  		return -EINVAL;
>  	}
>  
> -	ret = of_address_to_resource(node, 0, &r);
> -	if (ret)
> -		return ret;
> +	rmem = of_reserved_mem_lookup(node);
> +	of_node_put(node);
> +	if (!rmem) {
> +		dev_err(adsp->dev, "unable to resolve dtb memory-region\n");
> +		return -EINVAL;
> +	}
>  
> -	adsp->dtb_mem_phys = adsp->dtb_mem_reloc = r.start;
> -	adsp->dtb_mem_size = resource_size(&r);
> +	adsp->dtb_mem_phys = adsp->dtb_mem_reloc = rmem->base;
> +	adsp->dtb_mem_size = rmem->size;
>  	adsp->dtb_mem_region = devm_ioremap_wc(adsp->dev, adsp->dtb_mem_phys, adsp->dtb_mem_size);
>  	if (!adsp->dtb_mem_region) {
>  		dev_err(adsp->dev, "unable to map dtb memory region: %pa+%zx\n",
> -			&r.start, adsp->dtb_mem_size);
> +			&rmem->base, adsp->dtb_mem_size);
>  		return -EBUSY;
>  	}
>  
> @@ -584,29 +588,28 @@ static int adsp_alloc_memory_region(struct qcom_adsp *adsp)
>  
>  static int adsp_assign_memory_region(struct qcom_adsp *adsp)
>  {
> +	struct reserved_mem *rmem = NULL;
>  	struct qcom_scm_vmperm perm;
>  	struct device_node *node;
> -	struct resource r;
>  	int ret;
>  
>  	if (!adsp->region_assign_idx)
>  		return 0;
>  
>  	node = of_parse_phandle(adsp->dev->of_node, "memory-region", adsp->region_assign_idx);
> -	if (!node) {
> -		dev_err(adsp->dev, "missing shareable memory-region\n");
> +	if (node)
> +		rmem = of_reserved_mem_lookup(node);
> +	of_node_put(node);
> +	if (!rmem) {
> +		dev_err(adsp->dev, "unable to resolve shareable memory-region\n");
>  		return -EINVAL;
>  	}
>  
> -	ret = of_address_to_resource(node, 0, &r);
> -	if (ret)
> -		return ret;
> -
>  	perm.vmid = QCOM_SCM_VMID_MSS_MSA;
>  	perm.perm = QCOM_SCM_PERM_RW;
>  
> -	adsp->region_assign_phys = r.start;
> -	adsp->region_assign_size = resource_size(&r);
> +	adsp->region_assign_phys = rmem->base;
> +	adsp->region_assign_size = rmem->size;
>  	adsp->region_assign_perms = BIT(QCOM_SCM_VMID_HLOS);
>  
>  	ret = qcom_scm_assign_mem(adsp->region_assign_phys,
> diff --git a/drivers/remoteproc/qcom_wcnss.c b/drivers/remoteproc/qcom_wcnss.c
> index 1ed0647bc962..334a9c75dad6 100644
> --- a/drivers/remoteproc/qcom_wcnss.c
> +++ b/drivers/remoteproc/qcom_wcnss.c
> @@ -14,8 +14,8 @@
>  #include <linux/kernel.h>
>  #include <linux/module.h>
>  #include <linux/io.h>
> -#include <linux/of_address.h>
>  #include <linux/of_device.h>
> +#include <linux/of_reserved_mem.h>
>  #include <linux/platform_device.h>
>  #include <linux/pm_domain.h>
>  #include <linux/pm_runtime.h>
> @@ -506,27 +506,25 @@ static int wcnss_request_irq(struct qcom_wcnss *wcnss,
>  
>  static int wcnss_alloc_memory_region(struct qcom_wcnss *wcnss)
>  {
> +	struct reserved_mem *rmem = NULL;
>  	struct device_node *node;
> -	struct resource r;
> -	int ret;
>  
>  	node = of_parse_phandle(wcnss->dev->of_node, "memory-region", 0);
> -	if (!node) {
> -		dev_err(wcnss->dev, "no memory-region specified\n");
> +	if (node)
> +		rmem = of_reserved_mem_lookup(node);
> +	of_node_put(node);
> +
> +	if (!rmem) {
> +		dev_err(wcnss->dev, "unable to resolve memory-region\n");
>  		return -EINVAL;
>  	}
>  
> -	ret = of_address_to_resource(node, 0, &r);
> -	of_node_put(node);
> -	if (ret)
> -		return ret;
> -
> -	wcnss->mem_phys = wcnss->mem_reloc = r.start;
> -	wcnss->mem_size = resource_size(&r);
> +	wcnss->mem_phys = wcnss->mem_reloc = rmem->base;
> +	wcnss->mem_size = rmem->size;
>  	wcnss->mem_region = devm_ioremap_wc(wcnss->dev, wcnss->mem_phys, wcnss->mem_size);
>  	if (!wcnss->mem_region) {
>  		dev_err(wcnss->dev, "unable to map memory region: %pa+%zx\n",
> -			&r.start, wcnss->mem_size);
> +			&rmem->base, wcnss->mem_size);
>  		return -EBUSY;
>  	}
>  
> 
> ---
> base-commit: 06c2afb862f9da8dc5efa4b6076a0e48c3fbaaa5
> change-id: 20230529-rproc-of-rmem-7d931f61f64e
> 
> Best regards,

-- 
// Caleb (they/them)