[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <CAOD6ATobD8HCJWXeRgoXYaBBuKxy_TPj_AuWOfdPhJRF=Gxz5w@mail.gmail.com>
Date: Tue, 22 Apr 2014 18:53:51 +0530
From: Shaik Ameer Basha <shaik.samsung@...il.com>
To: Cho KyongHo <pullip.cho@...sung.com>
Cc: Linux ARM Kernel <linux-arm-kernel@...ts.infradead.org>,
Linux DeviceTree <devicetree@...r.kernel.org>,
Linux IOMMU <iommu@...ts.linux-foundation.org>,
Linux Kernel <linux-kernel@...r.kernel.org>,
Linux Samsung SOC <linux-samsung-soc@...r.kernel.org>,
Antonios Motakis <a.motakis@...tualopensystems.com>,
Grant Grundler <grundler@...omium.org>,
Joerg Roedel <joro@...tes.org>,
Kukjin Kim <kgene.kim@...sung.com>,
Prathyush <prathyush.k@...sung.com>,
Rahul Sharma <rahul.sharma@...sung.com>,
Sachin Kamat <sachin.kamat@...aro.org>,
Sylwester Nawrocki <s.nawrocki@...sung.com>,
Tomasz Figa <t.figa@...sung.com>,
Varun Sethi <Varun.Sethi@...escale.com>
Subject: Re: [PATCH v11 20/27] iommu/exynos: allow having multiple System MMUs
for a master H/W
Hi KyongHo Cho,
On Fri, Mar 14, 2014 at 10:40 AM, Cho KyongHo <pullip.cho@...sung.com> wrote:
> Some master device descriptor like fimc-is which is an abstraction
> of very complex H/W may have multiple System MMUs. For those devices,
> the design of the link between System MMU and its master H/W is needed
> to be reconsidered.
>
> A link structure, sysmmu_list_data is introduced that provides a link
> to master H/W and that has a pointer to the device descriptor of a
> System MMU. Given a device descriptor of a master H/W, it is possible
> to traverse all System MMUs that must be controlled along with the
> master H/W.
>
> Signed-off-by: Cho KyongHo <pullip.cho@...sung.com>
> ---
> drivers/iommu/exynos-iommu.c | 534 ++++++++++++++++++++++++++----------------
> 1 file changed, 333 insertions(+), 201 deletions(-)
>
> diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
> index 84ba29a..7489343 100644
> --- a/drivers/iommu/exynos-iommu.c
> +++ b/drivers/iommu/exynos-iommu.c
> @@ -128,6 +128,10 @@
> #define __master_clk_disable(data) __clk_gate_ctrl(data, clk_master, dis)
>
[snip]
> +static int __init __sysmmu_init_master(struct device *dev)
> +{
> + int ret;
> + int i = 0;
> + struct device_node *node;
> +
> + while ((node = of_parse_phandle(dev->of_node, "mmu-masters", i++))) {
> struct platform_device *master = of_find_device_by_node(node);
> + struct exynos_iommu_owner *owner;
> + struct sysmmu_list_data *list_data;
>
> if (!master) {
> dev_err(dev, "%s: mmu-master '%s' not found\n",
> __func__, node->name);
> - return -EINVAL;
> + ret = -EINVAL;
> + goto err;
> }
>
> - if (master->dev.archdata.iommu != NULL) {
> - dev_err(dev, "%s: '%s' is master of other MMU\n",
> - __func__, node->name);
> - return -EINVAL;
> + owner = master->dev.archdata.iommu;
> + if (!owner) {
> + owner = devm_kzalloc(dev, sizeof(*owner), GFP_KERNEL);
> + if (!owner) {
> + dev_err(dev,
> + "%s: Failed to allocate owner structure\n",
> + __func__);
> + ret = -ENOMEM;
> + goto err;
> + }
> +
> + INIT_LIST_HEAD(&owner->mmu_list);
> + INIT_LIST_HEAD(&owner->client);
> + owner->dev = &master->dev;
> + spin_lock_init(&owner->lock);
> +
> + master->dev.archdata.iommu = owner;
> }
>
> + list_data = devm_kzalloc(dev, sizeof(*list_data), GFP_KERNEL);
> + if (!list_data) {
> + dev_err(dev,
> + "%s: Failed to allocate sysmmu_list_data\n",
> + __func__);
> + ret = -ENOMEM;
> + goto err;
> + }
> +
> + INIT_LIST_HEAD(&list_data->entry);
> + list_data->sysmmu = dev;
> +
> /*
> - * archdata.iommu will be initialized with exynos_iommu_client
> - * in sysmmu_hook_driver_register().
> + * System MMUs are attached in the order of the presence
> + * in device tree
> */
> - master->dev.archdata.iommu = dev;
> + list_add_tail(&list_data->entry, &owner->mmu_list);
> }
>
> - data->sysmmu = dev;
> - rwlock_init(&data->lock);
> + return 0;
> +err:
> + while ((node = of_parse_phandle(dev->of_node, "mmu-masters", i++))) {
Don't we need to reinitialize variable 'i' here before using?
i = 0;
Regards,
Shaik Ameer Basha
> + struct platform_device *master = of_find_device_by_node(node);
> + struct exynos_iommu_owner *owner;
> + struct sysmmu_list_data *list_data;
>
> - platform_set_drvdata(pdev, data);
> + if (!master)
> + continue;
>
> - pm_runtime_enable(dev);
> - data->runtime_active = !pm_runtime_enabled(dev);
> + owner = master->dev.archdata.iommu;
> + if (!owner)
> + continue;
>
> - dev_dbg(dev, "Probed and initialized\n");
> - return 0;
> + for_each_sysmmu_list(owner->dev, list_data) {
> + if (list_data->sysmmu == dev) {
> + list_del(&list_data->entry);
> + kfree(list_data);
> + break;
> + }
> + }
> + }
> +
> + return ret;
> }
>
[snip]
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists