diff mbox series

[XEN,v8,15/22] xen/arm: ffa: add defines for sharing memory

Message ID 20230413071424.3273490-16-jens.wiklander@linaro.org (mailing list archive)
State New, archived
Headers show
Series Xen FF-A mediator | expand

Commit Message

Jens Wiklander April 13, 2023, 7:14 a.m. UTC 
Adds defines needed for sharing using the function FFA_MEM_SHARE and
friends.

Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
---
 xen/arch/arm/tee/ffa.c | 60 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 60 insertions(+)

Comments

Henry Wang April 13, 2023, 11:46 a.m. UTC | #1 
Hi Jens,

> -----Original Message-----
> Subject: [XEN PATCH v8 15/22] xen/arm: ffa: add defines for sharing memory
> 
> Adds defines needed for sharing using the function FFA_MEM_SHARE and
> friends.

Same as my comments in previous patches, I would suggest to also mention
the references in commit message.

> 
> Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
> ---
>  xen/arch/arm/tee/ffa.c | 60
> ++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 60 insertions(+)
> 
> + * FF-A doesn't have any direct requirments on GlobalPlatform or vice

Typo: s/requirements/requirements/

> + * versa, but an implementation can very well use FF-A in order to provide
> + * a GlobalPlatform interface on top.
> + *
> + * Global Platform specification for TEE requires that any TEE
> + * implementation should allow to share buffers with size of at least
> + * 512KB, defined in TEEC-1.0C page 24, Table 4-1,
> + * TEEC_CONFIG_SHAREDMEM_MAX_SIZE.
> + * Due to align issue mentioned above, we need to increase this

s/align issue/alignment issue/ ?

> + * value with one.
> + */
> +#define FFA_MAX_SHM_PAGE_COUNT          (SZ_512K / FFA_PAGE_SIZE + 1)
> +
> +/*
> + * Limits the number of shared buffers that guest can have at once. This
> + * is to prevent case, when guests tricks XEN into exhausting its own

Typo: s/tricks/trick/

> + * memory by allocating many small buffers. This value has been chosen
> + * arbitrary.

Typo: s/ arbitrary/arbitrarily/

> + */
> +#define FFA_MAX_SHM_COUNT               32
> +
> +/* FF-A-1.1-REL0 section 10.9.2 Memory region handle, page 167 */
> +#define FFA_HANDLE_HYP_FLAG             BIT(63, ULL)
> +#define FFA_HANDLE_INVALID              0xffffffffffffffffULL
> +
> +/*
> + * Memory attributes: Normal memory, Write-Back cacheable, Inner
> shareable
> + * Defined in FF-A-1.1-REL0 Table 10.18 at page 175.
> + */
> +#define FFA_NORMAL_MEM_REG_ATTR         0x2fU
> +/*
> + * Memory access permissions: Read-write
> + * Defined in FF-A-1.1-REL0 Table 10.15 at page 168.
> + */
> +#define FFA_MEM_ACC_RW                  0x2U
> +
> +/* FF-A-1.1-REL0 section 10.11.4 Flags usage, page 184-187 */
> +/* Clear memory before mapping in receiver */
> +#define FFA_MEMORY_REGION_FLAG_CLEAR            BIT(0, U)
> +/* Relayer may time slice this operation */
> +#define FFA_MEMORY_REGION_FLAG_TIME_SLICE       BIT(1, U)
> +/* Clear memory after receiver relinquishes it */
> +#define FFA_MEMORY_REGION_FLAG_CLEAR_RELINQUISH BIT(2, U)
> +/* Share memory transaction */
> +#define FFA_MEMORY_REGION_TRANSACTION_TYPE_SHARE (1U << 3)
> +

I confirm the values introduced in this patch are consistent with in-code
comments on top of them. Thanks for the pointer :)

With the typos corrected:
Reviewed-by: Henry Wang <Henry.Wang@arm.com>

Kind regards,
Henry


>  /*
>   * Flags and field values used for the MSG_SEND_DIRECT_REQ/RESP:
>   * BIT(31): Framework or partition message
> --
> 2.34.1
>
Jens Wiklander April 13, 2023, 2:18 p.m. UTC | #2 
Hi Henry,

On Thu, Apr 13, 2023 at 1:47 PM Henry Wang <Henry.Wang@arm.com> wrote:
>
> Hi Jens,
>
> > -----Original Message-----
> > Subject: [XEN PATCH v8 15/22] xen/arm: ffa: add defines for sharing memory
> >
> > Adds defines needed for sharing using the function FFA_MEM_SHARE and
> > friends.
>
> Same as my comments in previous patches, I would suggest to also mention
> the references in commit message.

OK, I'll add something.

>
> >
> > Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
> > ---
> >  xen/arch/arm/tee/ffa.c | 60
> > ++++++++++++++++++++++++++++++++++++++++++
> >  1 file changed, 60 insertions(+)
> >
> > + * FF-A doesn't have any direct requirments on GlobalPlatform or vice
>
> Typo: s/requirements/requirements/

OK

>
> > + * versa, but an implementation can very well use FF-A in order to provide
> > + * a GlobalPlatform interface on top.
> > + *
> > + * Global Platform specification for TEE requires that any TEE
> > + * implementation should allow to share buffers with size of at least
> > + * 512KB, defined in TEEC-1.0C page 24, Table 4-1,
> > + * TEEC_CONFIG_SHAREDMEM_MAX_SIZE.
> > + * Due to align issue mentioned above, we need to increase this
>
> s/align issue/alignment issue/ ?

Yes, I'll make it "the alignment issue".

>
> > + * value with one.
> > + */
> > +#define FFA_MAX_SHM_PAGE_COUNT          (SZ_512K / FFA_PAGE_SIZE + 1)
> > +
> > +/*
> > + * Limits the number of shared buffers that guest can have at once. This
> > + * is to prevent case, when guests tricks XEN into exhausting its own
>
> Typo: s/tricks/trick/

OK

>
> > + * memory by allocating many small buffers. This value has been chosen
> > + * arbitrary.
>
> Typo: s/ arbitrary/arbitrarily/

OK

>
> > + */
> > +#define FFA_MAX_SHM_COUNT               32
> > +
> > +/* FF-A-1.1-REL0 section 10.9.2 Memory region handle, page 167 */
> > +#define FFA_HANDLE_HYP_FLAG             BIT(63, ULL)
> > +#define FFA_HANDLE_INVALID              0xffffffffffffffffULL
> > +
> > +/*
> > + * Memory attributes: Normal memory, Write-Back cacheable, Inner
> > shareable
> > + * Defined in FF-A-1.1-REL0 Table 10.18 at page 175.
> > + */
> > +#define FFA_NORMAL_MEM_REG_ATTR         0x2fU
> > +/*
> > + * Memory access permissions: Read-write
> > + * Defined in FF-A-1.1-REL0 Table 10.15 at page 168.
> > + */
> > +#define FFA_MEM_ACC_RW                  0x2U
> > +
> > +/* FF-A-1.1-REL0 section 10.11.4 Flags usage, page 184-187 */
> > +/* Clear memory before mapping in receiver */
> > +#define FFA_MEMORY_REGION_FLAG_CLEAR            BIT(0, U)
> > +/* Relayer may time slice this operation */
> > +#define FFA_MEMORY_REGION_FLAG_TIME_SLICE       BIT(1, U)
> > +/* Clear memory after receiver relinquishes it */
> > +#define FFA_MEMORY_REGION_FLAG_CLEAR_RELINQUISH BIT(2, U)
> > +/* Share memory transaction */
> > +#define FFA_MEMORY_REGION_TRANSACTION_TYPE_SHARE (1U << 3)
> > +
>
> I confirm the values introduced in this patch are consistent with in-code
> comments on top of them. Thanks for the pointer :)

:-)

>
> With the typos corrected:
> Reviewed-by: Henry Wang <Henry.Wang@arm.com>

Great.

Thanks,
Jens

>
> Kind regards,
> Henry
>
>
> >  /*
> >   * Flags and field values used for the MSG_SEND_DIRECT_REQ/RESP:
> >   * BIT(31): Framework or partition message
> > --
> > 2.34.1
> >
>
diff mbox series

Patch

diff --git a/xen/arch/arm/tee/ffa.c b/xen/arch/arm/tee/ffa.c
index 74b8c517afb8..58c581c8ffc7 100644
--- a/xen/arch/arm/tee/ffa.c
+++ b/xen/arch/arm/tee/ffa.c
@@ -5,6 +5,14 @@ 
  * Arm Firmware Framework for ARMv8-A (FF-A) mediator
  *
  * Copyright (C) 2023  Linaro Limited
+ *
+ * References:
+ * FF-A-1.0-REL: FF-A specification version 1.0 available at
+ *               https://developer.arm.com/documentation/den0077/a
+ * FF-A-1.1-REL0: FF-A specification version 1.1 available at
+ *                https://developer.arm.com/documentation/den0077/e
+ * TEEC-1.0C: TEE Client API Specification version 1.0c available at
+ *            https://globalplatform.org/specs-library/tee-client-api-specification/
  */
 
 #include <xen/bitops.h>
@@ -80,6 +88,58 @@ 
  */
 #define FFA_MAX_RXTX_PAGE_COUNT         32
 
+/*
+ * Limit for shared buffer size. Please note that this define limits
+ * number of pages. But user buffer can be not aligned to a page
+ * boundary. So it is possible that user would not be able to share
+ * exactly FFA_MAX_SHM_BUFFER_PG * FFA_PAGE_SIZE bytes.
+ *
+ * FF-A doesn't have any direct requirments on GlobalPlatform or vice
+ * versa, but an implementation can very well use FF-A in order to provide
+ * a GlobalPlatform interface on top.
+ *
+ * Global Platform specification for TEE requires that any TEE
+ * implementation should allow to share buffers with size of at least
+ * 512KB, defined in TEEC-1.0C page 24, Table 4-1,
+ * TEEC_CONFIG_SHAREDMEM_MAX_SIZE.
+ * Due to align issue mentioned above, we need to increase this
+ * value with one.
+ */
+#define FFA_MAX_SHM_PAGE_COUNT          (SZ_512K / FFA_PAGE_SIZE + 1)
+
+/*
+ * Limits the number of shared buffers that guest can have at once. This
+ * is to prevent case, when guests tricks XEN into exhausting its own
+ * memory by allocating many small buffers. This value has been chosen
+ * arbitrary.
+ */
+#define FFA_MAX_SHM_COUNT               32
+
+/* FF-A-1.1-REL0 section 10.9.2 Memory region handle, page 167 */
+#define FFA_HANDLE_HYP_FLAG             BIT(63, ULL)
+#define FFA_HANDLE_INVALID              0xffffffffffffffffULL
+
+/*
+ * Memory attributes: Normal memory, Write-Back cacheable, Inner shareable
+ * Defined in FF-A-1.1-REL0 Table 10.18 at page 175.
+ */
+#define FFA_NORMAL_MEM_REG_ATTR         0x2fU
+/*
+ * Memory access permissions: Read-write
+ * Defined in FF-A-1.1-REL0 Table 10.15 at page 168.
+ */
+#define FFA_MEM_ACC_RW                  0x2U
+
+/* FF-A-1.1-REL0 section 10.11.4 Flags usage, page 184-187 */
+/* Clear memory before mapping in receiver */
+#define FFA_MEMORY_REGION_FLAG_CLEAR            BIT(0, U)
+/* Relayer may time slice this operation */
+#define FFA_MEMORY_REGION_FLAG_TIME_SLICE       BIT(1, U)
+/* Clear memory after receiver relinquishes it */
+#define FFA_MEMORY_REGION_FLAG_CLEAR_RELINQUISH BIT(2, U)
+/* Share memory transaction */
+#define FFA_MEMORY_REGION_TRANSACTION_TYPE_SHARE (1U << 3)
+
 /*
  * Flags and field values used for the MSG_SEND_DIRECT_REQ/RESP:
  * BIT(31): Framework or partition message