From: m.szyprowski@samsung•com (Marek Szyprowski)
To: linux-arm-kernel@lists•infradead.org
Subject: [RFC PATCH v4 1/8] iommu: provide early initialisation hook for IOMMU drivers
Date: Tue, 18 Nov 2014 13:28:03 +0100 [thread overview]
Message-ID: <546B3B53.6030202@samsung.com> (raw)
In-Reply-To: <1415991397-9618-2-git-send-email-will.deacon@arm.com>
Hello,
On 2014-11-14 19:56, Will Deacon wrote:
> IOMMU drivers must be initialised before any of their upstream devices,
> otherwise the relevant iommu_ops won't be configured for the bus in
> question. To solve this, a number of IOMMU drivers use initcalls to
> initialise the driver before anything has a chance to be probed.
>
> Whilst this solves the immediate problem, it leaves the job of probing
> the IOMMU completely separate from the iommu_ops to configure the IOMMU,
> which are called on a per-bus basis and require the driver to figure out
> exactly which instance of the IOMMU is being requested. In particular,
> the add_device callback simply passes a struct device to the driver,
> which then has to parse firmware tables or probe buses to identify the
> relevant IOMMU instance.
>
> This patch takes the first step in addressing this problem by adding an
> early initialisation pass for IOMMU drivers, giving them the ability to
> store some per-instance data in their iommu_ops structure and store that
> in their of_node. This can later be used when parsing OF masters to
> identify the IOMMU instance in question.
>
> Signed-off-by: Will Deacon <will.deacon@arm•com>
> ---
> drivers/iommu/of_iommu.c | 17 +++++++++++++++++
> include/asm-generic/vmlinux.lds.h | 2 ++
> include/linux/iommu.h | 2 ++
> include/linux/of_iommu.h | 25 +++++++++++++++++++++++++
> 4 files changed, 46 insertions(+)
>
> diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
> index e550ccb7634e..89b903406968 100644
> --- a/drivers/iommu/of_iommu.c
> +++ b/drivers/iommu/of_iommu.c
> @@ -22,6 +22,9 @@
> #include <linux/of.h>
> #include <linux/of_iommu.h>
>
> +static const struct of_device_id __iommu_of_table_sentinel
> + __used __section(__iommu_of_table_end);
> +
> /**
> * of_get_dma_window - Parse *dma-window property and returns 0 if found.
> *
> @@ -89,3 +92,17 @@ int of_get_dma_window(struct device_node *dn, const char *prefix, int index,
> return 0;
> }
> EXPORT_SYMBOL_GPL(of_get_dma_window);
> +
> +void __init of_iommu_init(void)
> +{
> + struct device_node *np;
> + const struct of_device_id *match, *matches = &__iommu_of_table;
> +
> + for_each_matching_node_and_match(np, matches, &match) {
> + const of_iommu_init_fn init_fn = match->data;
> +
> + if (init_fn(np))
> + pr_err("Failed to initialise IOMMU %s\n",
> + of_node_full_name(np));
> + }
> +}
> diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
> index aa70cbda327c..bee5d683074d 100644
> --- a/include/asm-generic/vmlinux.lds.h
> +++ b/include/asm-generic/vmlinux.lds.h
> @@ -164,6 +164,7 @@
> #define CLKSRC_OF_TABLES() OF_TABLE(CONFIG_CLKSRC_OF, clksrc)
> #define IRQCHIP_OF_MATCH_TABLE() OF_TABLE(CONFIG_IRQCHIP, irqchip)
> #define CLK_OF_TABLES() OF_TABLE(CONFIG_COMMON_CLK, clk)
> +#define IOMMU_OF_TABLES() OF_TABLE(CONFIG_OF_IOMMU, iommu)
> #define RESERVEDMEM_OF_TABLES() OF_TABLE(CONFIG_OF_RESERVED_MEM, reservedmem)
> #define CPU_METHOD_OF_TABLES() OF_TABLE(CONFIG_SMP, cpu_method)
> #define EARLYCON_OF_TABLES() OF_TABLE(CONFIG_SERIAL_EARLYCON, earlycon)
> @@ -497,6 +498,7 @@
> CLK_OF_TABLES() \
> RESERVEDMEM_OF_TABLES() \
> CLKSRC_OF_TABLES() \
> + IOMMU_OF_TABLES() \
> CPU_METHOD_OF_TABLES() \
> KERNEL_DTB() \
> IRQCHIP_OF_MATCH_TABLE() \
> diff --git a/include/linux/iommu.h b/include/linux/iommu.h
> index e6a7c9ff72f2..7b83f9f8e11d 100644
> --- a/include/linux/iommu.h
> +++ b/include/linux/iommu.h
> @@ -103,6 +103,7 @@ enum iommu_attr {
> * @domain_get_attr: Query domain attributes
> * @domain_set_attr: Change domain attributes
> * @pgsize_bitmap: bitmap of supported page sizes
> + * @priv: per-instance data private to the iommu driver
> */
> struct iommu_ops {
> bool (*capable)(enum iommu_cap);
> @@ -133,6 +134,7 @@ struct iommu_ops {
> u32 (*domain_get_windows)(struct iommu_domain *domain);
>
> unsigned long pgsize_bitmap;
> + void *priv;
> };
>
> #define IOMMU_GROUP_NOTIFY_ADD_DEVICE 1 /* Device added */
> diff --git a/include/linux/of_iommu.h b/include/linux/of_iommu.h
> index 51a560f34bca..81447e0f68b5 100644
> --- a/include/linux/of_iommu.h
> +++ b/include/linux/of_iommu.h
> @@ -1,12 +1,17 @@
> #ifndef __OF_IOMMU_H
> #define __OF_IOMMU_H
>
> +#include <linux/iommu.h>
> +#include <linux/of.h>
> +
> #ifdef CONFIG_OF_IOMMU
>
> 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);
> +
> #else
>
> static inline int of_get_dma_window(struct device_node *dn, const char *prefix,
> @@ -16,6 +21,26 @@ static inline int of_get_dma_window(struct device_node *dn, const char *prefix,
> return -EINVAL;
> }
>
> +static inline void of_iommu_init(void) { }
> +
> #endif /* CONFIG_OF_IOMMU */
>
> +static inline void of_iommu_set_ops(struct device_node *np,
> + struct iommu_ops *ops)
I think it will be reasonable to change the second argument to "const
struct iommu_ops *ops" to match other code that uses it.
> +{
> + np->data = ops;
The above change require adding a cast:
np->data = (struct iommu_ops *)ops;
> +}
> +
> +static inline struct iommu_ops *of_iommu_get_ops(struct device_node *np)
> +{
> + return np->data;
> +}
> +
> +extern struct of_device_id __iommu_of_table;
> +
> +typedef int (*of_iommu_init_fn)(struct device_node *);
> +
> +#define IOMMU_OF_DECLARE(name, compat, fn) \
> + _OF_DECLARE(iommu, name, compat, fn, of_iommu_init_fn)
> +
> #endif /* __OF_IOMMU_H */
Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland
next prev parent reply other threads:[~2014-11-18 12:28 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-11-14 18:56 [RFC PATCH v4 0/8] Introduce automatic DMA configuration for IOMMU masters Will Deacon
2014-11-14 18:56 ` [RFC PATCH v4 1/8] iommu: provide early initialisation hook for IOMMU drivers Will Deacon
2014-11-18 12:28 ` Marek Szyprowski [this message]
2014-11-14 18:56 ` [RFC PATCH v4 2/8] dma-mapping: replace set_arch_dma_coherent_ops with arch_setup_dma_ops Will Deacon
2014-11-14 18:56 ` [RFC PATCH v4 3/8] iommu: add new iommu_ops callback for adding an OF device Will Deacon
2014-11-14 18:56 ` [RFC PATCH v4 4/8] iommu: provide helper function to configure an IOMMU for an of master Will Deacon
2014-11-14 18:56 ` [RFC PATCH v4 5/8] dma-mapping: detect and configure IOMMU in of_dma_configure Will Deacon
2014-11-14 18:56 ` [RFC PATCH v4 6/8] dma-mapping: set dma segment properties " Will Deacon
2014-11-25 13:05 ` Robin Murphy
2014-11-26 11:37 ` Will Deacon
2014-11-14 18:56 ` [RFC PATCH v4 7/8] arm: call iommu_init before of_platform_populate Will Deacon
2014-11-14 18:56 ` [RFC PATCH v4 8/8] arm: dma-mapping: plumb our iommu mapping ops into arch_setup_dma_ops Will Deacon
2014-11-17 11:29 ` Robin Murphy
2014-11-17 11:41 ` Will Deacon
2014-11-14 19:11 ` [RFC PATCH v4 0/8] Introduce automatic DMA configuration for IOMMU masters Arnd Bergmann
2014-11-14 19:27 ` Will Deacon
2014-11-14 20:01 ` Arnd Bergmann
2015-01-19 16:06 ` Will Deacon
2015-01-20 16:56 ` Laurent Pinchart
2015-01-21 14:48 ` Will Deacon
2015-01-21 15:02 ` Laurent Pinchart
2014-11-19 11:21 ` Marek Szyprowski
2014-11-19 11:41 ` Will Deacon
2014-11-25 7:35 ` Marek Szyprowski
2014-11-26 17:47 ` Will Deacon
2014-11-28 13:03 ` jroedel at suse.de
2014-11-28 13:19 ` Will Deacon
2014-12-15 17:21 ` Laurent Pinchart
2014-12-15 17:34 ` Will Deacon
2014-12-15 17:55 ` Laurent Pinchart
2014-11-25 13:15 ` Robin Murphy
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=546B3B53.6030202@samsung.com \
--to=m.szyprowski@samsung$(echo .)com \
--cc=linux-arm-kernel@lists$(echo .)infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox