diff mbox series

[V3,15/16] crypto/nx: Get NX capabilities for GZIP coprocessor type

Message ID e5fff6adbf3ce7769b0efe4846f39dbc6c795dd1.camel@linux.ibm.com (mailing list archive)
State Not Applicable
Delegated to: Herbert Xu
Headers show
Series Enable VAS and NX-GZIP support on powerVM | expand

Commit Message

Haren Myneni April 17, 2021, 9:12 p.m. UTC
phyp provides NX capabilities which gives recommended minimum
compression / decompression length and maximum request buffer size
in bytes.

Changes to get NX overall capabilities which points to the specific
features phyp supports. Then retrieve NXGZIP specific capabilities.

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
---
 drivers/crypto/nx/nx-common-pseries.c | 83 +++++++++++++++++++++++++++
 1 file changed, 83 insertions(+)

Comments

Herbert Xu April 22, 2021, 6:56 a.m. UTC | #1
On Sat, Apr 17, 2021 at 02:12:51PM -0700, Haren Myneni wrote:
> 
> phyp provides NX capabilities which gives recommended minimum
> compression / decompression length and maximum request buffer size
> in bytes.
> 
> Changes to get NX overall capabilities which points to the specific
> features phyp supports. Then retrieve NXGZIP specific capabilities.
> 
> Signed-off-by: Haren Myneni <haren@linux.ibm.com>
> ---
>  drivers/crypto/nx/nx-common-pseries.c | 83 +++++++++++++++++++++++++++
>  1 file changed, 83 insertions(+)

Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Nicholas Piggin May 10, 2021, 6:38 a.m. UTC | #2
Excerpts from Haren Myneni's message of April 18, 2021 7:12 am:
> 
> phyp provides NX capabilities which gives recommended minimum
> compression / decompression length and maximum request buffer size
> in bytes.
> 
> Changes to get NX overall capabilities which points to the specific
> features phyp supports. Then retrieve NXGZIP specific capabilities.
> 
> Signed-off-by: Haren Myneni <haren@linux.ibm.com>
> ---
>  drivers/crypto/nx/nx-common-pseries.c | 83 +++++++++++++++++++++++++++
>  1 file changed, 83 insertions(+)
> 
> diff --git a/drivers/crypto/nx/nx-common-pseries.c b/drivers/crypto/nx/nx-common-pseries.c
> index 9a40fca8a9e6..49224870d05e 100644
> --- a/drivers/crypto/nx/nx-common-pseries.c
> +++ b/drivers/crypto/nx/nx-common-pseries.c
> @@ -9,6 +9,7 @@
>   */
>  
>  #include <asm/vio.h>
> +#include <asm/hvcall.h>
>  #include <asm/vas.h>
>  
>  #include "nx-842.h"
> @@ -20,6 +21,24 @@ MODULE_DESCRIPTION("842 H/W Compression driver for IBM Power processors");
>  MODULE_ALIAS_CRYPTO("842");
>  MODULE_ALIAS_CRYPTO("842-nx");
>  
> +struct nx_ct_capabs_be {

What does "ct" mean? I've seen it in a few other places too.

> +	__be64	descriptor;
> +	__be64	req_max_processed_len;	/* Max bytes in one GZIP request */
> +	__be64	min_compress_len;	/* Min compression size in bytes */
> +	__be64	min_decompress_len;	/* Min decompression size in bytes */
> +} __packed __aligned(0x1000);
> +
> +struct nx_ct_capabs {
> +	char	name[VAS_DESCR_LEN + 1];
> +	u64	descriptor;
> +	u64	req_max_processed_len;	/* Max bytes in one GZIP request */
> +	u64	min_compress_len;	/* Min compression in bytes */
> +	u64	min_decompress_len;	/* Min decompression in bytes */
> +};
> +
> +u64 capab_feat = 0;

Why is this here and not a local variable?

> +struct nx_ct_capabs nx_ct_capab;

It's okay and generally better to use the same name as the struct name
in this situation, i.e.,

"struct nx_ct_capabs nx_ct_capabs"

(modulo static / caps / etc)

Thanks,
Nick
Haren Myneni May 10, 2021, 8:44 p.m. UTC | #3
On Mon, 2021-05-10 at 16:38 +1000, Nicholas Piggin wrote:
> Excerpts from Haren Myneni's message of April 18, 2021 7:12 am:
> > phyp provides NX capabilities which gives recommended minimum
> > compression / decompression length and maximum request buffer size
> > in bytes.
> > 
> > Changes to get NX overall capabilities which points to the specific
> > features phyp supports. Then retrieve NXGZIP specific capabilities.
> > 
> > Signed-off-by: Haren Myneni <haren@linux.ibm.com>
> > ---
> >  drivers/crypto/nx/nx-common-pseries.c | 83
> > +++++++++++++++++++++++++++
> >  1 file changed, 83 insertions(+)
> > 
> > diff --git a/drivers/crypto/nx/nx-common-pseries.c
> > b/drivers/crypto/nx/nx-common-pseries.c
> > index 9a40fca8a9e6..49224870d05e 100644
> > --- a/drivers/crypto/nx/nx-common-pseries.c
> > +++ b/drivers/crypto/nx/nx-common-pseries.c
> > @@ -9,6 +9,7 @@
> >   */
> >  
> >  #include <asm/vio.h>
> > +#include <asm/hvcall.h>
> >  #include <asm/vas.h>
> >  
> >  #include "nx-842.h"
> > @@ -20,6 +21,24 @@ MODULE_DESCRIPTION("842 H/W Compression driver
> > for IBM Power processors");
> >  MODULE_ALIAS_CRYPTO("842");
> >  MODULE_ALIAS_CRYPTO("842-nx");
> >  
> > +struct nx_ct_capabs_be {
> 
> What does "ct" mean? I've seen it in a few other places too.

ct means coprocessor type such as 842 and GZIP. phyp provides only GZIP
capabilities right now. But this struct may be extended to other types
in future.

> 
> > +	__be64	descriptor;
> > +	__be64	req_max_processed_len;	/* Max bytes in one GZIP
> > request */
> > +	__be64	min_compress_len;	/* Min compression size in
> > bytes */
> > +	__be64	min_decompress_len;	/* Min decompression size
> > in bytes */
> > +} __packed __aligned(0x1000);
> > +
> > +struct nx_ct_capabs {
> > +	char	name[VAS_DESCR_LEN + 1];
> > +	u64	descriptor;
> > +	u64	req_max_processed_len;	/* Max bytes in one GZIP request */
> > +	u64	min_compress_len;	/* Min compression in bytes */
> > +	u64	min_decompress_len;	/* Min decompression in bytes */
> > +};
> > +
> > +u64 capab_feat = 0;
> 
> Why is this here and not a local variable?

capab_feat is used to add / delete sysfs entries.

> 
> > +struct nx_ct_capabs nx_ct_capab;
> 
> It's okay and generally better to use the same name as the struct
> name
> in this situation, i.e.,
> 
> "struct nx_ct_capabs nx_ct_capabs"
> 
> (modulo static / caps / etc)

Sure, will change.

> 
> Thanks,
> Nick
diff mbox series

Patch

diff --git a/drivers/crypto/nx/nx-common-pseries.c b/drivers/crypto/nx/nx-common-pseries.c
index 9a40fca8a9e6..49224870d05e 100644
--- a/drivers/crypto/nx/nx-common-pseries.c
+++ b/drivers/crypto/nx/nx-common-pseries.c
@@ -9,6 +9,7 @@ 
  */
 
 #include <asm/vio.h>
+#include <asm/hvcall.h>
 #include <asm/vas.h>
 
 #include "nx-842.h"
@@ -20,6 +21,24 @@  MODULE_DESCRIPTION("842 H/W Compression driver for IBM Power processors");
 MODULE_ALIAS_CRYPTO("842");
 MODULE_ALIAS_CRYPTO("842-nx");
 
+struct nx_ct_capabs_be {
+	__be64	descriptor;
+	__be64	req_max_processed_len;	/* Max bytes in one GZIP request */
+	__be64	min_compress_len;	/* Min compression size in bytes */
+	__be64	min_decompress_len;	/* Min decompression size in bytes */
+} __packed __aligned(0x1000);
+
+struct nx_ct_capabs {
+	char	name[VAS_DESCR_LEN + 1];
+	u64	descriptor;
+	u64	req_max_processed_len;	/* Max bytes in one GZIP request */
+	u64	min_compress_len;	/* Min compression in bytes */
+	u64	min_decompress_len;	/* Min decompression in bytes */
+};
+
+u64 capab_feat = 0;
+struct nx_ct_capabs nx_ct_capab;
+
 static struct nx842_constraints nx842_pseries_constraints = {
 	.alignment =	DDE_BUFFER_ALIGN,
 	.multiple =	DDE_BUFFER_LAST_MULT,
@@ -1066,6 +1085,66 @@  static void nx842_remove(struct vio_dev *viodev)
 	kfree(old_devdata);
 }
 
+/*
+ * Get NX capabilities from pHyp.
+ * Only NXGZIP capabilities are available right now and these values
+ * are available through sysfs.
+ */
+static void __init nxct_get_capabilities(void)
+{
+	struct vas_all_capabs_be *capabs_be;
+	struct nx_ct_capabs_be *nxc_be;
+	int rc;
+
+	capabs_be = kmalloc(sizeof(*capabs_be), GFP_KERNEL);
+	if (!capabs_be)
+		return;
+	/*
+	 * Get NX overall capabilities with feature type=0
+	 */
+	rc = plpar_vas_query_capabilities(H_QUERY_NX_CAPABILITIES, 0,
+					  (u64)virt_to_phys(capabs_be));
+	if (rc)
+		goto out;
+
+	capab_feat = be64_to_cpu(capabs_be->feat_type);
+	/*
+	 * NX-GZIP feature available
+	 */
+	if (capab_feat & VAS_NX_GZIP_FEAT_BIT) {
+		nxc_be = kmalloc(sizeof(*nxc_be), GFP_KERNEL);
+		if (!nxc_be)
+			goto out;
+		/*
+		 * Get capabilities for NX-GZIP feature
+		 */
+		rc = plpar_vas_query_capabilities(H_QUERY_NX_CAPABILITIES,
+						  VAS_NX_GZIP_FEAT,
+						  (u64)virt_to_phys(nxc_be));
+	} else {
+		pr_err("NX-GZIP feature is not available\n");
+		rc = -EINVAL;
+	}
+
+	if (!rc) {
+		snprintf(nx_ct_capab.name, VAS_DESCR_LEN + 1, "%.8s",
+			 (char *)&nxc_be->descriptor);
+		nx_ct_capab.descriptor = be64_to_cpu(nxc_be->descriptor);
+		nx_ct_capab.req_max_processed_len =
+				be64_to_cpu(nxc_be->req_max_processed_len);
+		nx_ct_capab.min_compress_len =
+				be64_to_cpu(nxc_be->min_compress_len);
+		nx_ct_capab.min_decompress_len =
+				be64_to_cpu(nxc_be->min_decompress_len);
+	} else {
+		capab_feat = 0;
+	}
+
+	kfree(nxc_be);
+out:
+	kfree(capabs_be);
+}
+
 static const struct vio_device_id nx842_vio_driver_ids[] = {
 	{"ibm,compression-v1", "ibm,compression"},
 	{"", ""},
@@ -1093,6 +1172,10 @@  static int __init nx842_pseries_init(void)
 		return -ENOMEM;
 
 	RCU_INIT_POINTER(devdata, new_devdata);
+	/*
+	 * Get NX capabilities from pHyp which is used for NX-GZIP.
+	 */
+	nxct_get_capabilities();
 
 	ret = vio_register_driver(&nx842_vio_driver);
 	if (ret) {