lkml.org 
[lkml]   [2023]   [Mar]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RESEND PATCH] driver/perf: arm-cmn: support ACPI probe

Hi Jing,

On Thu, 23 Mar 2023, Jing Zhang wrote:
> ACPI companion devices call insert_resource() in platform_device_add()
> to claim the device resources. If the resources are claimed again before
> ioremap(), and the addresses of multiple resources overlap, it will
> return -BUSY, causing the driver to fail to load.
>
> For example, the CMN700 on my machine is set with two resources similar
> to CMN600, and the overlap of resource addresses makes the CMN driver
> unable to match my CMN700. The error log:

I thought that the two address ranges were only needed for CMN-600?
I guess, the specification doesn't explicitly forbid giving two ranges for
CMN700 although the example shows just one.

>
> [ 12.016837] arm-cmn ARMHC700:00: can't request region for resource [mem 0x40000000-0x4fffffff]
> [ 12.028230] arm-cmn: probe of ARMHC700:00 failed with error -16
> [ 12.036832] arm-cmn ARMHC700:01: can't request region for resource [mem 0x40040000000-0x4004fffffff]
> [ 12.051289] arm-cmn: probe of ARMHC700:01 failed with error -16
>
> So let ACPI companion devices call arm_cmn_acpi_probe() and not claim
> resource again. In addition, the arm_cmn_acpi_probe() and
> arm_cmn_of_probe() functions are refactored to make them compatible
> with both CMN600 and CMN-ANY.
>
> Fixes: 61ec1d875812 ("perf/arm-cmn: Demarcate CMN-600 specifics")
> Signed-off-by: Jing Zhang <renyu.zj@linux.alibaba.com>
> ---
> drivers/perf/arm-cmn.c | 57 ++++++++++++++++++++++++++++++++------------------
> 1 file changed, 37 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/perf/arm-cmn.c b/drivers/perf/arm-cmn.c
> index 1deb61b..beb3b37 100644
> --- a/drivers/perf/arm-cmn.c
> +++ b/drivers/perf/arm-cmn.c
> @@ -2206,7 +2206,7 @@ static int arm_cmn_discover(struct arm_cmn *cmn, unsigned int rgn_offset)
> return 0;
> }
>
> -static int arm_cmn600_acpi_probe(struct platform_device *pdev, struct arm_cmn *cmn)
> +static int arm_cmn_acpi_probe(struct platform_device *pdev, struct arm_cmn *cmn)
> {
> struct resource *cfg, *root;
>
> @@ -2214,12 +2214,21 @@ static int arm_cmn600_acpi_probe(struct platform_device *pdev, struct arm_cmn *c
> if (!cfg)
> return -EINVAL;
>
> - root = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> - if (!root)
> - return -EINVAL;
> + /* If ACPI defines more than one resource, such as cmn-600, then there may be
> + * a deviation between ROOTNODEBASE and PERIPHBASE, and ROOTNODEBASE can
> + * be obtained from the second resource. Otherwise, it can be considered that
> + * ROOT NODE BASE is PERIPHBASE. This is compatible with cmn-600 and cmn-any.
> + */
> + if (pdev->num_resources > 1) {
> + root = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> + if (!root)
> + return -EINVAL;
>
> - if (!resource_contains(cfg, root))
> - swap(cfg, root);
> + if (!resource_contains(cfg, root))
> + swap(cfg, root);
> + } else {
> + root = cfg;
> + }
> /*
> * Note that devm_ioremap_resource() is dumb and won't let the platform
> * device claim cfg when the ACPI companion device has already claimed
> @@ -2227,17 +2236,30 @@ static int arm_cmn600_acpi_probe(struct platform_device *pdev, struct arm_cmn *c
> * appropriate name, we don't really need to do it again here anyway.
> */
> cmn->base = devm_ioremap(cmn->dev, cfg->start, resource_size(cfg));
> - if (!cmn->base)
> - return -ENOMEM;
> + if (IS_ERR(cmn->base))
> + return PTR_ERR(cmn->base);

I believe, devm_ioremap() returns NULL in case of error

Cheers, Ilkka


>
> return root->start - cfg->start;
> }
>
> -static int arm_cmn600_of_probe(struct device_node *np)
> +static int arm_cmn_of_probe(struct platform_device *pdev, struct arm_cmn *cmn)
> {
> u32 rootnode;
> + int ret;
> +
> + cmn->base = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(cmn->base))
> + return PTR_ERR(cmn->base);
>
> - return of_property_read_u32(np, "arm,root-node", &rootnode) ?: rootnode;
> + /* If of_property_read_u32() return -EINVAL, it means that device tree has
> + * not define root-node, and root-node will return 0, which is compatible
> + * with cmn-600 and cmn-any.
> + */
> + ret = of_property_read_u32(pdev->dev.of_node, "arm,root-node", &rootnode);
> + if (ret == -EINVAL)
> + return 0;
> +
> + return rootnode;
> }
>
> static int arm_cmn_probe(struct platform_device *pdev)
> @@ -2255,16 +2277,11 @@ static int arm_cmn_probe(struct platform_device *pdev)
> cmn->model = (unsigned long)device_get_match_data(cmn->dev);
> platform_set_drvdata(pdev, cmn);
>
> - if (cmn->model == CMN600 && has_acpi_companion(cmn->dev)) {
> - rootnode = arm_cmn600_acpi_probe(pdev, cmn);
> - } else {
> - rootnode = 0;
> - cmn->base = devm_platform_ioremap_resource(pdev, 0);
> - if (IS_ERR(cmn->base))
> - return PTR_ERR(cmn->base);
> - if (cmn->model == CMN600)
> - rootnode = arm_cmn600_of_probe(pdev->dev.of_node);
> - }
> + if (has_acpi_companion(cmn->dev))
> + rootnode = arm_cmn_acpi_probe(pdev, cmn);
> + else
> + rootnode = arm_cmn_of_probe(pdev, cmn);
> +
> if (rootnode < 0)
> return rootnode;
>
> --
> 1.8.3.1
>
>

\
 
 \ /
  Last update: 2023-03-27 01:15    [W:0.044 / U:0.492 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site