Re: [PATCH] of: iommu: make of_iommu_init() postcore_initcall_sync

From: Rich Felker
Date: Sat Apr 23 2016 - 14:08:21 EST


On Sat, Apr 23, 2016 at 05:33:07PM +0800, Kefeng Wang wrote:
> The of_iommu_init() is called multiple times by arch code,
> make it postcore_initcall_sync, then we can drop relevant
> calls fully.
>
> Note, the IOMMUs should have a chance to perform some basic
> initialisation before we start adding masters to them. So
> postcore_initcall_sync is good choice, it ensures of_iommu_init()
> called before of_platform_populate.
>
> Cc: Arnd Bergmann <arnd@xxxxxxxx>
> Cc: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
> Cc: Rich Felker <dalias@xxxxxxxx>
> Cc: Rob Herring <robh+dt@xxxxxxxxxx>
> Cc: Robin Murphy <robin.murphy@xxxxxxx>
> Cc: Will Deacon <will.deacon@xxxxxxx>
> Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>

Acked-by: Rich Felker <dalias@xxxxxxxx>

> ---
> arch/arm/kernel/setup.c | 2 --
> arch/arm64/kernel/setup.c | 2 --
> arch/sh/boards/of-generic.c | 2 --
> drivers/iommu/of_iommu.c | 5 ++++-
> include/linux/of_iommu.h | 2 --
> 5 files changed, 4 insertions(+), 9 deletions(-)
>
> diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
> index 2c4bea3..18a29a0 100644
> --- a/arch/arm/kernel/setup.c
> +++ b/arch/arm/kernel/setup.c
> @@ -19,7 +19,6 @@
> #include <linux/bootmem.h>
> #include <linux/seq_file.h>
> #include <linux/screen_info.h>
> -#include <linux/of_iommu.h>
> #include <linux/of_platform.h>
> #include <linux/init.h>
> #include <linux/kexec.h>
> @@ -902,7 +901,6 @@ static int __init customize_machine(void)
> * machine from the device tree, if no callback is provided,
> * otherwise we would always need an init_machine callback.
> */
> - of_iommu_init();
> if (machine_desc->init_machine)
> machine_desc->init_machine();
> #ifdef CONFIG_OF
> diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
> index 9dc6776..e20b64f 100644
> --- a/arch/arm64/kernel/setup.c
> +++ b/arch/arm64/kernel/setup.c
> @@ -39,7 +39,6 @@
> #include <linux/fs.h>
> #include <linux/proc_fs.h>
> #include <linux/memblock.h>
> -#include <linux/of_iommu.h>
> #include <linux/of_fdt.h>
> #include <linux/of_platform.h>
> #include <linux/efi.h>
> @@ -365,7 +364,6 @@ void __init setup_arch(char **cmdline_p)
> static int __init arm64_device_init(void)
> {
> if (of_have_populated_dt()) {
> - of_iommu_init();
> of_platform_populate(NULL, of_default_bus_match_table,
> NULL, NULL);
> } else if (acpi_disabled) {
> diff --git a/arch/sh/boards/of-generic.c b/arch/sh/boards/of-generic.c
> index bf3a166..b4d4313 100644
> --- a/arch/sh/boards/of-generic.c
> +++ b/arch/sh/boards/of-generic.c
> @@ -11,7 +11,6 @@
> #include <linux/of.h>
> #include <linux/of_platform.h>
> #include <linux/of_fdt.h>
> -#include <linux/of_iommu.h>
> #include <linux/clocksource.h>
> #include <linux/irqchip.h>
> #include <linux/clk-provider.h>
> @@ -185,7 +184,6 @@ static int __init sh_of_device_init(void)
> {
> pr_info("SH generic board support: populating platform devices\n");
> if (of_have_populated_dt()) {
> - of_iommu_init();
> of_platform_populate(NULL, of_default_bus_match_table,
> NULL, NULL);
> } else {
> diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
> index 5fea665..04cc80f 100644
> --- a/drivers/iommu/of_iommu.c
> +++ b/drivers/iommu/of_iommu.c
> @@ -174,7 +174,7 @@ err_put_node:
> return NULL;
> }
>
> -void __init of_iommu_init(void)
> +static int __init of_iommu_init(void)
> {
> struct device_node *np;
> const struct of_device_id *match, *matches = &__iommu_of_table;
> @@ -186,4 +186,7 @@ void __init of_iommu_init(void)
> pr_err("Failed to initialise IOMMU %s\n",
> of_node_full_name(np));
> }
> +
> + return 0;
> }
> +postcore_initcall_sync(of_iommu_init);
> diff --git a/include/linux/of_iommu.h b/include/linux/of_iommu.h
> index ffbe470..e2c2e71 100644
> --- a/include/linux/of_iommu.h
> +++ b/include/linux/of_iommu.h
> @@ -11,7 +11,6 @@ extern int of_get_dma_window(struct device_node *dn, const char *prefix,
> int index, unsigned long *busno, dma_addr_t *addr,
> size_t *size);
>
> -extern void of_iommu_init(void);
> extern struct iommu_ops *of_iommu_configure(struct device *dev,
> struct device_node *master_np);
>
> @@ -24,7 +23,6 @@ static inline int of_get_dma_window(struct device_node *dn, const char *prefix,
> return -EINVAL;
> }
>
> -static inline void of_iommu_init(void) { }
> static inline struct iommu_ops *of_iommu_configure(struct device *dev,
> struct device_node *master_np)
> {
> --
> 2.6.0.GIT