| Message ID | 1373021097-32420-3-git-send-email-hdoyu@nvidia.com |
|---|---|
| State | Superseded, archived |
| Headers | show |
On 07/05/2013 04:44 AM, Hiroshi Doyu wrote: > Populate AHB/IOMMU earlier than others. IOMMU depends on AHB. IOMMU > needs to be instanciated earlier than others so that IOMMU can > register other platform devices as IOMMU'able. Once IOMMU is > populated, IOMMU/AHB nodes are detached to prevent another > registeration. Hmmm. I'm still in two minds about this. If just the IOMMU was needed, then this wouldn't be too bad. But then there's the dependency on the AHB device too. And in general, there could be, say, a dependency on a SoC power-controller, clock controller, reset module, etc. This could become a huge slippery slope. Modelling the IOMMU as an explicit bus with the bus-master-capable devices underneath it would make everything work automatically... > diff --git a/arch/arm/mach-tegra/tegra.c b/arch/arm/mach-tegra/tegra.c > +static void tegra_of_platform_populate_iommu(void) > +{ > + int i; > + struct platform_device *pdev; > + const char * const path[] = {"/ahb", "/iommu", }; > + > + for (i = 0; i < ARRAY_SIZE(path); i++) { > + struct device_node *np; > + > + np = of_find_node_by_path(path[i]); I think this should at least look up the nodes by compatible value. See how e.g. mach-tegra/pmc.c finds the right DT node. -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/arm/mach-tegra/tegra.c b/arch/arm/mach-tegra/tegra.c index 0d1e412..fe432d1 100644 --- a/arch/arm/mach-tegra/tegra.c +++ b/arch/arm/mach-tegra/tegra.c @@ -80,6 +80,26 @@ static struct of_dev_auxdata tegra20_auxdata_lookup[] __initdata = { {} }; +static void tegra_of_platform_populate_iommu(void) +{ + int i; + struct platform_device *pdev; + const char * const path[] = {"/ahb", "/iommu", }; + + for (i = 0; i < ARRAY_SIZE(path); i++) { + struct device_node *np; + + np = of_find_node_by_path(path[i]); + if (!np) + break; + + pdev = of_platform_device_create(np, NULL, NULL); + of_node_put(np); + if (!pdev) + break; + } +} + static void __init tegra_dt_init(void) { struct soc_device_attribute *soc_dev_attr; @@ -107,6 +127,8 @@ static void __init tegra_dt_init(void) parent = soc_device_to_device(soc_dev); + tegra_of_platform_populate_iommu(); + /* * Finished with the static registrations now; fill in the missing * devices
Populate AHB/IOMMU earlier than others. IOMMU depends on AHB. IOMMU needs to be instanciated earlier than others so that IOMMU can register other platform devices as IOMMU'able. Once IOMMU is populated, IOMMU/AHB nodes are detached to prevent another registeration. Signed-off-by: Hiroshi Doyu <hdoyu@nvidia.com> --- arch/arm/mach-tegra/tegra.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+)