[PATCH RESEND,v3,0/4] drivers: uio: new driver uio_fsl_85xx_cache_sram

[PATCH RESEND,v3,0/4] drivers: uio: new driver uio_fsl_85xx_cache_sram

[Wang Wenhu]

This series add a new uio driver for freescale 85xx platforms to
access the Cache-Sram form user level. This is extremely helpful
for the user-space applications that require high performance memory
accesses.

It fixes the compile errors and warning of the hardware level drivers
and implements the uio driver in uio_fsl_85xx_cache_sram.c.

Changes since v1:
 * Addressed comments from Greg K-H
 * Moved kfree(info->name) into uio_info_free_internal()

Changes since v2:
 * Drop the patch that modifies Kconfigs of arch/powerpc/platforms
   and modified the sequence of patches:
    01:dropped, 02->03, 03->02, 04->01, 05->04
 * Addressed comments from Greg, Scott and Christophe
 * Use "uiomem->internal_addr" as if condition for sram memory free,
   and memset the uiomem entry
 * Modified of_match_table make the driver apart from Cache-Sram HW info
   which belong to the HW level driver fsl_85xx_cache_sram to match
 * Use roundup_pow_of_two for align calc(really learned a lot from Christophe)
 * Remove useless clear block of uiomem entries.
 * Use UIO_INFO_VER micro for info->version, and define it as
   "devicetree,pseudo", meaning this is pseudo device and probed from
   device tree configuration
 * Select FSL_85XX_CACHE_SRAM rather than depends on it

Wang Wenhu (4):
  powerpc: sysdev: fix compile error for fsl_85xx_l2ctlr
  powerpc: sysdev: fix compile error for fsl_85xx_cache_sram
  powerpc: sysdev: fix compile warning for fsl_85xx_cache_sram
  drivers: uio: new driver for fsl_85xx_cache_sram

 arch/powerpc/sysdev/fsl_85xx_cache_sram.c |   3 +-
 arch/powerpc/sysdev/fsl_85xx_l2ctlr.c     |   1 +
 drivers/uio/Kconfig                       |   9 ++
 drivers/uio/Makefile                      |   1 +
 drivers/uio/uio_fsl_85xx_cache_sram.c     | 158 ++++++++++++++++++++++
 5 files changed, 171 insertions(+), 1 deletion(-)
 create mode 100644 drivers/uio/uio_fsl_85xx_cache_sram.c

-- 
2.17.1

[PATCH RESEND, v3, 0/4] drivers: uio: new driver uio_fsl_85xx_cache_sram

[Wang Wenhu]

This series add a new uio driver for freescale 85xx platforms to
access the Cache-Sram form user level. This is extremely helpful
for the user-space applications that require high performance memory
accesses.

It fixes the compile errors and warning of the hardware level drivers
and implements the uio driver in uio_fsl_85xx_cache_sram.c.

Changes since v1:
 * Addressed comments from Greg K-H
 * Moved kfree(info->name) into uio_info_free_internal()

Changes since v2:
 * Drop the patch that modifies Kconfigs of arch/powerpc/platforms
   and modified the sequence of patches:
    01:dropped, 02->03, 03->02, 04->01, 05->04
 * Addressed comments from Greg, Scott and Christophe
 * Use "uiomem->internal_addr" as if condition for sram memory free,
   and memset the uiomem entry
 * Modified of_match_table make the driver apart from Cache-Sram HW info
   which belong to the HW level driver fsl_85xx_cache_sram to match
 * Use roundup_pow_of_two for align calc(really learned a lot from Christophe)
 * Remove useless clear block of uiomem entries.
 * Use UIO_INFO_VER micro for info->version, and define it as
   "devicetree,pseudo", meaning this is pseudo device and probed from
   device tree configuration
 * Select FSL_85XX_CACHE_SRAM rather than depends on it

Wang Wenhu (4):
  powerpc: sysdev: fix compile error for fsl_85xx_l2ctlr
  powerpc: sysdev: fix compile error for fsl_85xx_cache_sram
  powerpc: sysdev: fix compile warning for fsl_85xx_cache_sram
  drivers: uio: new driver for fsl_85xx_cache_sram

 arch/powerpc/sysdev/fsl_85xx_cache_sram.c |   3 +-
 arch/powerpc/sysdev/fsl_85xx_l2ctlr.c     |   1 +
 drivers/uio/Kconfig                       |   9 ++
 drivers/uio/Makefile                      |   1 +
 drivers/uio/uio_fsl_85xx_cache_sram.c     | 158 ++++++++++++++++++++++
 5 files changed, 171 insertions(+), 1 deletion(-)
 create mode 100644 drivers/uio/uio_fsl_85xx_cache_sram.c

-- 
2.17.1

[PATCH RESEND,v3,1/4] powerpc: sysdev: fix compile error for fsl_85xx_l2ctlr

[Wang Wenhu]

Include "linux/of_address.h" to fix the compile error for
mpc85xx_l2ctlr_of_probe() when compiling fsl_85xx_cache_sram.c.

  CC      arch/powerpc/sysdev/fsl_85xx_l2ctlr.o
arch/powerpc/sysdev/fsl_85xx_l2ctlr.c: In function ‘mpc85xx_l2ctlr_of_probe’:
arch/powerpc/sysdev/fsl_85xx_l2ctlr.c:90:11: error: implicit declaration of function ‘of_iomap’; did you mean ‘pci_iomap’? [-Werror=implicit-function-declaration]
  l2ctlr = of_iomap(dev->dev.of_node, 0);
           ^~~~~~~~
           pci_iomap
arch/powerpc/sysdev/fsl_85xx_l2ctlr.c:90:9: error: assignment makes pointer from integer without a cast [-Werror=int-conversion]
  l2ctlr = of_iomap(dev->dev.of_node, 0);
         ^
cc1: all warnings being treated as errors
scripts/Makefile.build:267: recipe for target 'arch/powerpc/sysdev/fsl_85xx_l2ctlr.o' failed
make[2]: *** [arch/powerpc/sysdev/fsl_85xx_l2ctlr.o] Error 1

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Scott Wood <oss@buserror.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Fixes: 6db92cc9d07d ("powerpc/85xx: add cache-sram support")
Signed-off-by: Wang Wenhu <wenhu.wang@vivo.com>
---
Changes since v1:
 * None
Changes since v2:
 * None
---
 arch/powerpc/sysdev/fsl_85xx_l2ctlr.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/sysdev/fsl_85xx_l2ctlr.c b/arch/powerpc/sysdev/fsl_85xx_l2ctlr.c
index 2d0af0c517bb..7533572492f0 100644
--- a/arch/powerpc/sysdev/fsl_85xx_l2ctlr.c
+++ b/arch/powerpc/sysdev/fsl_85xx_l2ctlr.c
@@ -10,6 +10,7 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of_platform.h>
+#include <linux/of_address.h>
 #include <asm/io.h>
 
 #include "fsl_85xx_cache_ctlr.h"
-- 
2.17.1

[PATCH RESEND, v3, 1/4] powerpc: sysdev: fix compile error for fsl_85xx_l2ctlr

[Wang Wenhu]

Include "linux/of_address.h" to fix the compile error for
mpc85xx_l2ctlr_of_probe() when compiling fsl_85xx_cache_sram.c.

  CC      arch/powerpc/sysdev/fsl_85xx_l2ctlr.o
arch/powerpc/sysdev/fsl_85xx_l2ctlr.c: In function ‘mpc85xx_l2ctlr_of_probe’:
arch/powerpc/sysdev/fsl_85xx_l2ctlr.c:90:11: error: implicit declaration of function ‘of_iomap’; did you mean ‘pci_iomap’? [-Werror=implicit-function-declaration]
  l2ctlr = of_iomap(dev->dev.of_node, 0);
           ^~~~~~~~
           pci_iomap
arch/powerpc/sysdev/fsl_85xx_l2ctlr.c:90:9: error: assignment makes pointer from integer without a cast [-Werror=int-conversion]
  l2ctlr = of_iomap(dev->dev.of_node, 0);
         ^
cc1: all warnings being treated as errors
scripts/Makefile.build:267: recipe for target 'arch/powerpc/sysdev/fsl_85xx_l2ctlr.o' failed
make[2]: *** [arch/powerpc/sysdev/fsl_85xx_l2ctlr.o] Error 1

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Scott Wood <oss@buserror.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Fixes: 6db92cc9d07d ("powerpc/85xx: add cache-sram support")
Signed-off-by: Wang Wenhu <wenhu.wang@vivo.com>
---
Changes since v1:
 * None
Changes since v2:
 * None
---
 arch/powerpc/sysdev/fsl_85xx_l2ctlr.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/sysdev/fsl_85xx_l2ctlr.c b/arch/powerpc/sysdev/fsl_85xx_l2ctlr.c
index 2d0af0c517bb..7533572492f0 100644
--- a/arch/powerpc/sysdev/fsl_85xx_l2ctlr.c
+++ b/arch/powerpc/sysdev/fsl_85xx_l2ctlr.c
@@ -10,6 +10,7 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of_platform.h>
+#include <linux/of_address.h>
 #include <asm/io.h>
 
 #include "fsl_85xx_cache_ctlr.h"
-- 
2.17.1

[PATCH RESEND,v3,2/4] powerpc: sysdev: fix compile error for fsl_85xx_cache_sram

[Wang Wenhu]

Include linux/io.h into fsl_85xx_cache_sram.c to fix the
implicit-declaration compile error when building Cache-Sram.

arch/powerpc/sysdev/fsl_85xx_cache_sram.c: In function ‘instantiate_cache_sram’:
arch/powerpc/sysdev/fsl_85xx_cache_sram.c:97:26: error: implicit declaration of function ‘ioremap_coherent’; did you mean ‘bitmap_complement’? [-Werror=implicit-function-declaration]
  cache_sram->base_virt = ioremap_coherent(cache_sram->base_phys,
                          ^~~~~~~~~~~~~~~~
                          bitmap_complement
arch/powerpc/sysdev/fsl_85xx_cache_sram.c:97:24: error: assignment makes pointer from integer without a cast [-Werror=int-conversion]
  cache_sram->base_virt = ioremap_coherent(cache_sram->base_phys,
                        ^
arch/powerpc/sysdev/fsl_85xx_cache_sram.c:123:2: error: implicit declaration of function ‘iounmap’; did you mean ‘roundup’? [-Werror=implicit-function-declaration]
  iounmap(cache_sram->base_virt);
  ^~~~~~~
  roundup
cc1: all warnings being treated as errors

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Scott Wood <oss@buserror.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Fixes: 6db92cc9d07d ("powerpc/85xx: add cache-sram support")
Signed-off-by: WANG Wenhu <wenhu.wang@vivo.com>
---
Changes since v1:
 * None
Changes since v2:
 * None
---
 arch/powerpc/sysdev/fsl_85xx_cache_sram.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/sysdev/fsl_85xx_cache_sram.c b/arch/powerpc/sysdev/fsl_85xx_cache_sram.c
index f6c665dac725..be3aef4229d7 100644
--- a/arch/powerpc/sysdev/fsl_85xx_cache_sram.c
+++ b/arch/powerpc/sysdev/fsl_85xx_cache_sram.c
@@ -17,6 +17,7 @@
 #include <linux/of_platform.h>
 #include <asm/pgtable.h>
 #include <asm/fsl_85xx_cache_sram.h>
+#include <linux/io.h>
 
 #include "fsl_85xx_cache_ctlr.h"
 
-- 
2.17.1

[PATCH RESEND, v3, 2/4] powerpc: sysdev: fix compile error for fsl_85xx_cache_sram

[Wang Wenhu]

Include linux/io.h into fsl_85xx_cache_sram.c to fix the
implicit-declaration compile error when building Cache-Sram.

arch/powerpc/sysdev/fsl_85xx_cache_sram.c: In function ‘instantiate_cache_sram’:
arch/powerpc/sysdev/fsl_85xx_cache_sram.c:97:26: error: implicit declaration of function ‘ioremap_coherent’; did you mean ‘bitmap_complement’? [-Werror=implicit-function-declaration]
  cache_sram->base_virt = ioremap_coherent(cache_sram->base_phys,
                          ^~~~~~~~~~~~~~~~
                          bitmap_complement
arch/powerpc/sysdev/fsl_85xx_cache_sram.c:97:24: error: assignment makes pointer from integer without a cast [-Werror=int-conversion]
  cache_sram->base_virt = ioremap_coherent(cache_sram->base_phys,
                        ^
arch/powerpc/sysdev/fsl_85xx_cache_sram.c:123:2: error: implicit declaration of function ‘iounmap’; did you mean ‘roundup’? [-Werror=implicit-function-declaration]
  iounmap(cache_sram->base_virt);
  ^~~~~~~
  roundup
cc1: all warnings being treated as errors

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Scott Wood <oss@buserror.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Fixes: 6db92cc9d07d ("powerpc/85xx: add cache-sram support")
Signed-off-by: WANG Wenhu <wenhu.wang@vivo.com>
---
Changes since v1:
 * None
Changes since v2:
 * None
---
 arch/powerpc/sysdev/fsl_85xx_cache_sram.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/sysdev/fsl_85xx_cache_sram.c b/arch/powerpc/sysdev/fsl_85xx_cache_sram.c
index f6c665dac725..be3aef4229d7 100644
--- a/arch/powerpc/sysdev/fsl_85xx_cache_sram.c
+++ b/arch/powerpc/sysdev/fsl_85xx_cache_sram.c
@@ -17,6 +17,7 @@
 #include <linux/of_platform.h>
 #include <asm/pgtable.h>
 #include <asm/fsl_85xx_cache_sram.h>
+#include <linux/io.h>
 
 #include "fsl_85xx_cache_ctlr.h"
 
-- 
2.17.1

[PATCH RESEND,v3,3/4] powerpc: sysdev: fix compile warning for fsl_85xx_cache_sram

[Wang Wenhu]

Function instantiate_cache_sram should not be linked into the init
section for its caller mpc85xx_l2ctlr_of_probe is none-__init.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Scott Wood <oss@buserror.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Fixes: 6db92cc9d07d ("powerpc/85xx: add cache-sram support")
Signed-off-by: Wang Wenhu <wenhu.wang@vivo.com>

Warning information:
  MODPOST vmlinux.o
WARNING: modpost: vmlinux.o(.text+0x1e540): Section mismatch in reference from the function mpc85xx_l2ctlr_of_probe() to the function .init.text:instantiate_cache_sram()
The function mpc85xx_l2ctlr_of_probe() references
the function __init instantiate_cache_sram().
This is often because mpc85xx_l2ctlr_of_probe lacks a __init
annotation or the annotation of instantiate_cache_sram is wrong.
---
Changes since v1:
 * None
Changes since v2:
 * None
---
 arch/powerpc/sysdev/fsl_85xx_cache_sram.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/sysdev/fsl_85xx_cache_sram.c b/arch/powerpc/sysdev/fsl_85xx_cache_sram.c
index be3aef4229d7..3de5ac8382c0 100644
--- a/arch/powerpc/sysdev/fsl_85xx_cache_sram.c
+++ b/arch/powerpc/sysdev/fsl_85xx_cache_sram.c
@@ -68,7 +68,7 @@ void mpc85xx_cache_sram_free(void *ptr)
 }
 EXPORT_SYMBOL(mpc85xx_cache_sram_free);
 
-int __init instantiate_cache_sram(struct platform_device *dev,
+int instantiate_cache_sram(struct platform_device *dev,
 		struct sram_parameters sram_params)
 {
 	int ret = 0;
-- 
2.17.1

[PATCH RESEND, v3, 3/4] powerpc: sysdev: fix compile warning for fsl_85xx_cache_sram

[Wang Wenhu]

Function instantiate_cache_sram should not be linked into the init
section for its caller mpc85xx_l2ctlr_of_probe is none-__init.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Scott Wood <oss@buserror.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Fixes: 6db92cc9d07d ("powerpc/85xx: add cache-sram support")
Signed-off-by: Wang Wenhu <wenhu.wang@vivo.com>

Warning information:
  MODPOST vmlinux.o
WARNING: modpost: vmlinux.o(.text+0x1e540): Section mismatch in reference from the function mpc85xx_l2ctlr_of_probe() to the function .init.text:instantiate_cache_sram()
The function mpc85xx_l2ctlr_of_probe() references
the function __init instantiate_cache_sram().
This is often because mpc85xx_l2ctlr_of_probe lacks a __init
annotation or the annotation of instantiate_cache_sram is wrong.
---
Changes since v1:
 * None
Changes since v2:
 * None
---
 arch/powerpc/sysdev/fsl_85xx_cache_sram.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/sysdev/fsl_85xx_cache_sram.c b/arch/powerpc/sysdev/fsl_85xx_cache_sram.c
index be3aef4229d7..3de5ac8382c0 100644
--- a/arch/powerpc/sysdev/fsl_85xx_cache_sram.c
+++ b/arch/powerpc/sysdev/fsl_85xx_cache_sram.c
@@ -68,7 +68,7 @@ void mpc85xx_cache_sram_free(void *ptr)
 }
 EXPORT_SYMBOL(mpc85xx_cache_sram_free);
 
-int __init instantiate_cache_sram(struct platform_device *dev,
+int instantiate_cache_sram(struct platform_device *dev,
 		struct sram_parameters sram_params)
 {
 	int ret = 0;
-- 
2.17.1

[PATCH RESEND,v3,4/4] drivers: uio: new driver for fsl_85xx_cache_sram

[Wang Wenhu]

A driver for freescale 85xx platforms to access the Cache-Sram form
user level. This is extremely helpful for some user-space applications
that require high performance memory accesses.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Scott Wood <oss@buserror.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Wang Wenhu <wenhu.wang@vivo.com>
---
Changes since v1:
 * Addressed comments from Greg K-H
 * Moved kfree(info->name) into uio_info_free_internal()
Changes since v2:
 * Addressed comments from Greg, Scott and Christophe
 * Use "uiomem->internal_addr" as if condition for sram memory free,
   and memset the uiomem entry
 * Modified of_match_table make the driver apart from Cache-Sram HW info
   which belong to the HW level driver fsl_85xx_cache_sram to match
 * Use roundup_pow_of_two for align calculation
 * Remove useless clear block of uiomem entries.
 * Use UIO_INFO_VER micro for info->version, and define it as
   "devicetree,pseudo", meaning this is pseudo device and probed from
   device tree configuration
 * Select FSL_85XX_CACHE_SRAM rather than depends on it
---
 drivers/uio/Kconfig                   |   9 ++
 drivers/uio/Makefile                  |   1 +
 drivers/uio/uio_fsl_85xx_cache_sram.c | 158 ++++++++++++++++++++++++++
 3 files changed, 168 insertions(+)
 create mode 100644 drivers/uio/uio_fsl_85xx_cache_sram.c

diff --git a/drivers/uio/Kconfig b/drivers/uio/Kconfig
index 202ee81cfc2b..9c3b47461b71 100644
--- a/drivers/uio/Kconfig
+++ b/drivers/uio/Kconfig
@@ -105,6 +105,15 @@ config UIO_NETX
 	  To compile this driver as a module, choose M here; the module
 	  will be called uio_netx.
 
+config UIO_FSL_85XX_CACHE_SRAM
+	tristate "Freescale 85xx Cache-Sram driver"
+	depends on FSL_SOC_BOOKE && PPC32
+	select FSL_85XX_CACHE_SRAM
+	help
+	  Generic driver for accessing the Cache-Sram form user level. This
+	  is extremely helpful for some user-space applications that require
+	  high performance memory accesses.
+
 config UIO_FSL_ELBC_GPCM
 	tristate "eLBC/GPCM driver"
 	depends on FSL_LBC
diff --git a/drivers/uio/Makefile b/drivers/uio/Makefile
index c285dd2a4539..be2056cffc21 100644
--- a/drivers/uio/Makefile
+++ b/drivers/uio/Makefile
@@ -10,4 +10,5 @@ obj-$(CONFIG_UIO_NETX)	+= uio_netx.o
 obj-$(CONFIG_UIO_PRUSS)         += uio_pruss.o
 obj-$(CONFIG_UIO_MF624)         += uio_mf624.o
 obj-$(CONFIG_UIO_FSL_ELBC_GPCM)	+= uio_fsl_elbc_gpcm.o
+obj-$(CONFIG_UIO_FSL_85XX_CACHE_SRAM)	+= uio_fsl_85xx_cache_sram.o
 obj-$(CONFIG_UIO_HV_GENERIC)	+= uio_hv_generic.o
diff --git a/drivers/uio/uio_fsl_85xx_cache_sram.c b/drivers/uio/uio_fsl_85xx_cache_sram.c
new file mode 100644
index 000000000000..8701df695307
--- /dev/null
+++ b/drivers/uio/uio_fsl_85xx_cache_sram.c
@@ -0,0 +1,158 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020 Vivo Communication Technology Co. Ltd.
+ * Copyright (C) 2020 Wang Wenhu <wenhu.wang@vivo.com>
+ * All rights reserved.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/uio_driver.h>
+#include <linux/stringify.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <asm/fsl_85xx_cache_sram.h>
+
+#define DRIVER_NAME	"uio_fsl_85xx_cache_sram"
+#define UIO_INFO_VER	"devicetree,pseudo"
+#define UIO_NAME	"uio_cache_sram"
+
+static void uio_info_free_internal(struct uio_info *info)
+{
+	struct uio_mem *uiomem = info->mem;
+
+	while (uiomem < &info->mem[MAX_UIO_MAPS]) {
+		if (uiomem->internal_addr) {
+			mpc85xx_cache_sram_free(uiomem->internal_addr);
+			kfree(uiomem->name);
+			memset(uiomem, 0, sizeof(*uiomem));
+		}
+		uiomem++;
+	}
+
+	kfree(info->name);
+}
+
+static int uio_fsl_85xx_cache_sram_probe(struct platform_device *pdev)
+{
+	struct device_node *parent = pdev->dev.of_node;
+	struct device_node *node = NULL;
+	struct uio_info *info;
+	struct uio_mem *uiomem;
+	const char *dt_name;
+	u32 mem_size;
+	int ret;
+
+	/* alloc uio_info for one device */
+	info = kzalloc(sizeof(*info), GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+
+	/* get optional uio name */
+	if (of_property_read_string(parent, "uio_name", &dt_name))
+		dt_name = UIO_NAME;
+
+	info->name = kstrdup(dt_name, GFP_KERNEL);
+	if (!info->name) {
+		ret = -ENOMEM;
+		goto err_info_free;
+	}
+
+	uiomem = info->mem;
+	for_each_child_of_node(parent, node) {
+		void *virt;
+		phys_addr_t phys;
+
+		ret = of_property_read_u32(node, "cache-mem-size", &mem_size);
+		if (ret) {
+			ret = -EINVAL;
+			goto err_info_free_internal;
+		}
+
+		if (mem_size == 0) {
+			dev_err(&pdev->dev, "cache-mem-size should not be 0\n");
+			ret = -EINVAL;
+			goto err_info_free_internal;
+		}
+
+		virt = mpc85xx_cache_sram_alloc(mem_size,
+						&phys,
+						roundup_pow_of_two(mem_size));
+		if (!virt) {
+			/* mpc85xx_cache_sram_alloc to define the real cause */
+			ret = -ENOMEM;
+			goto err_info_free_internal;
+		}
+
+		uiomem->memtype = UIO_MEM_PHYS;
+		uiomem->addr = phys;
+		uiomem->size = mem_size;
+		uiomem->name = kstrdup(node->name, GFP_KERNEL);;
+		uiomem->internal_addr = virt;
+		uiomem++;
+
+		if (uiomem >= &info->mem[MAX_UIO_MAPS]) {
+			dev_warn(&pdev->dev, "more than %d uio-maps for device.\n",
+				 MAX_UIO_MAPS);
+			break;
+		}
+	}
+
+	if (uiomem == info->mem) {
+		dev_err(&pdev->dev, "error no valid uio-map configured\n");
+		ret = -EINVAL;
+		goto err_info_free_internal;
+	}
+
+	info->version = UIO_INFO_VER;
+
+	/* register uio device */
+	if (uio_register_device(&pdev->dev, info)) {
+		dev_err(&pdev->dev, "uio registration failed\n");
+		ret = -ENODEV;
+		goto err_info_free_internal;
+	}
+
+	platform_set_drvdata(pdev, info);
+
+	return 0;
+err_info_free_internal:
+	uio_info_free_internal(info);
+err_info_free:
+	kfree(info);
+	return ret;
+}
+
+static int uio_fsl_85xx_cache_sram_remove(struct platform_device *pdev)
+{
+	struct uio_info *info = platform_get_drvdata(pdev);
+
+	uio_unregister_device(info);
+
+	uio_info_free_internal(info);
+
+	kfree(info);
+
+	return 0;
+}
+
+static const struct of_device_id uio_mpc85xx_l2ctlr_of_match[] = {
+	{	.compatible = "uio,mpc85xx-cache-sram",	},
+	{},
+};
+
+static struct platform_driver uio_fsl_85xx_cache_sram = {
+	.probe = uio_fsl_85xx_cache_sram_probe,
+	.remove = uio_fsl_85xx_cache_sram_remove,
+	.driver = {
+		.name = DRIVER_NAME,
+		.owner = THIS_MODULE,
+		.of_match_table	= uio_mpc85xx_l2ctlr_of_match,
+	},
+};
+
+module_platform_driver(uio_fsl_85xx_cache_sram);
+
+MODULE_AUTHOR("Wang Wenhu <wenhu.wang@vivo.com>");
+MODULE_DESCRIPTION("Freescale MPC85xx Cache-Sram UIO Platform Driver");
+MODULE_ALIAS("platform:" DRIVER_NAME);
+MODULE_LICENSE("GPL v2");
-- 
2.17.1

[PATCH RESEND, v3, 4/4] drivers: uio: new driver for fsl_85xx_cache_sram

[Wang Wenhu]

A driver for freescale 85xx platforms to access the Cache-Sram form
user level. This is extremely helpful for some user-space applications
that require high performance memory accesses.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Scott Wood <oss@buserror.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Wang Wenhu <wenhu.wang@vivo.com>
---
Changes since v1:
 * Addressed comments from Greg K-H
 * Moved kfree(info->name) into uio_info_free_internal()
Changes since v2:
 * Addressed comments from Greg, Scott and Christophe
 * Use "uiomem->internal_addr" as if condition for sram memory free,
   and memset the uiomem entry
 * Modified of_match_table make the driver apart from Cache-Sram HW info
   which belong to the HW level driver fsl_85xx_cache_sram to match
 * Use roundup_pow_of_two for align calculation
 * Remove useless clear block of uiomem entries.
 * Use UIO_INFO_VER micro for info->version, and define it as
   "devicetree,pseudo", meaning this is pseudo device and probed from
   device tree configuration
 * Select FSL_85XX_CACHE_SRAM rather than depends on it
---
 drivers/uio/Kconfig                   |   9 ++
 drivers/uio/Makefile                  |   1 +
 drivers/uio/uio_fsl_85xx_cache_sram.c | 158 ++++++++++++++++++++++++++
 3 files changed, 168 insertions(+)
 create mode 100644 drivers/uio/uio_fsl_85xx_cache_sram.c

diff --git a/drivers/uio/Kconfig b/drivers/uio/Kconfig
index 202ee81cfc2b..9c3b47461b71 100644
--- a/drivers/uio/Kconfig
+++ b/drivers/uio/Kconfig
@@ -105,6 +105,15 @@ config UIO_NETX
 	  To compile this driver as a module, choose M here; the module
 	  will be called uio_netx.
 
+config UIO_FSL_85XX_CACHE_SRAM
+	tristate "Freescale 85xx Cache-Sram driver"
+	depends on FSL_SOC_BOOKE && PPC32
+	select FSL_85XX_CACHE_SRAM
+	help
+	  Generic driver for accessing the Cache-Sram form user level. This
+	  is extremely helpful for some user-space applications that require
+	  high performance memory accesses.
+
 config UIO_FSL_ELBC_GPCM
 	tristate "eLBC/GPCM driver"
 	depends on FSL_LBC
diff --git a/drivers/uio/Makefile b/drivers/uio/Makefile
index c285dd2a4539..be2056cffc21 100644
--- a/drivers/uio/Makefile
+++ b/drivers/uio/Makefile
@@ -10,4 +10,5 @@ obj-$(CONFIG_UIO_NETX)	+= uio_netx.o
 obj-$(CONFIG_UIO_PRUSS)         += uio_pruss.o
 obj-$(CONFIG_UIO_MF624)         += uio_mf624.o
 obj-$(CONFIG_UIO_FSL_ELBC_GPCM)	+= uio_fsl_elbc_gpcm.o
+obj-$(CONFIG_UIO_FSL_85XX_CACHE_SRAM)	+= uio_fsl_85xx_cache_sram.o
 obj-$(CONFIG_UIO_HV_GENERIC)	+= uio_hv_generic.o
diff --git a/drivers/uio/uio_fsl_85xx_cache_sram.c b/drivers/uio/uio_fsl_85xx_cache_sram.c
new file mode 100644
index 000000000000..8701df695307
--- /dev/null
+++ b/drivers/uio/uio_fsl_85xx_cache_sram.c
@@ -0,0 +1,158 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020 Vivo Communication Technology Co. Ltd.
+ * Copyright (C) 2020 Wang Wenhu <wenhu.wang@vivo.com>
+ * All rights reserved.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/uio_driver.h>
+#include <linux/stringify.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <asm/fsl_85xx_cache_sram.h>
+
+#define DRIVER_NAME	"uio_fsl_85xx_cache_sram"
+#define UIO_INFO_VER	"devicetree,pseudo"
+#define UIO_NAME	"uio_cache_sram"
+
+static void uio_info_free_internal(struct uio_info *info)
+{
+	struct uio_mem *uiomem = info->mem;
+
+	while (uiomem < &info->mem[MAX_UIO_MAPS]) {
+		if (uiomem->internal_addr) {
+			mpc85xx_cache_sram_free(uiomem->internal_addr);
+			kfree(uiomem->name);
+			memset(uiomem, 0, sizeof(*uiomem));
+		}
+		uiomem++;
+	}
+
+	kfree(info->name);
+}
+
+static int uio_fsl_85xx_cache_sram_probe(struct platform_device *pdev)
+{
+	struct device_node *parent = pdev->dev.of_node;
+	struct device_node *node = NULL;
+	struct uio_info *info;
+	struct uio_mem *uiomem;
+	const char *dt_name;
+	u32 mem_size;
+	int ret;
+
+	/* alloc uio_info for one device */
+	info = kzalloc(sizeof(*info), GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+
+	/* get optional uio name */
+	if (of_property_read_string(parent, "uio_name", &dt_name))
+		dt_name = UIO_NAME;
+
+	info->name = kstrdup(dt_name, GFP_KERNEL);
+	if (!info->name) {
+		ret = -ENOMEM;
+		goto err_info_free;
+	}
+
+	uiomem = info->mem;
+	for_each_child_of_node(parent, node) {
+		void *virt;
+		phys_addr_t phys;
+
+		ret = of_property_read_u32(node, "cache-mem-size", &mem_size);
+		if (ret) {
+			ret = -EINVAL;
+			goto err_info_free_internal;
+		}
+
+		if (mem_size == 0) {
+			dev_err(&pdev->dev, "cache-mem-size should not be 0\n");
+			ret = -EINVAL;
+			goto err_info_free_internal;
+		}
+
+		virt = mpc85xx_cache_sram_alloc(mem_size,
+						&phys,
+						roundup_pow_of_two(mem_size));
+		if (!virt) {
+			/* mpc85xx_cache_sram_alloc to define the real cause */
+			ret = -ENOMEM;
+			goto err_info_free_internal;
+		}
+
+		uiomem->memtype = UIO_MEM_PHYS;
+		uiomem->addr = phys;
+		uiomem->size = mem_size;
+		uiomem->name = kstrdup(node->name, GFP_KERNEL);;
+		uiomem->internal_addr = virt;
+		uiomem++;
+
+		if (uiomem >= &info->mem[MAX_UIO_MAPS]) {
+			dev_warn(&pdev->dev, "more than %d uio-maps for device.\n",
+				 MAX_UIO_MAPS);
+			break;
+		}
+	}
+
+	if (uiomem == info->mem) {
+		dev_err(&pdev->dev, "error no valid uio-map configured\n");
+		ret = -EINVAL;
+		goto err_info_free_internal;
+	}
+
+	info->version = UIO_INFO_VER;
+
+	/* register uio device */
+	if (uio_register_device(&pdev->dev, info)) {
+		dev_err(&pdev->dev, "uio registration failed\n");
+		ret = -ENODEV;
+		goto err_info_free_internal;
+	}
+
+	platform_set_drvdata(pdev, info);
+
+	return 0;
+err_info_free_internal:
+	uio_info_free_internal(info);
+err_info_free:
+	kfree(info);
+	return ret;
+}
+
+static int uio_fsl_85xx_cache_sram_remove(struct platform_device *pdev)
+{
+	struct uio_info *info = platform_get_drvdata(pdev);
+
+	uio_unregister_device(info);
+
+	uio_info_free_internal(info);
+
+	kfree(info);
+
+	return 0;
+}
+
+static const struct of_device_id uio_mpc85xx_l2ctlr_of_match[] = {
+	{	.compatible = "uio,mpc85xx-cache-sram",	},
+	{},
+};
+
+static struct platform_driver uio_fsl_85xx_cache_sram = {
+	.probe = uio_fsl_85xx_cache_sram_probe,
+	.remove = uio_fsl_85xx_cache_sram_remove,
+	.driver = {
+		.name = DRIVER_NAME,
+		.owner = THIS_MODULE,
+		.of_match_table	= uio_mpc85xx_l2ctlr_of_match,
+	},
+};
+
+module_platform_driver(uio_fsl_85xx_cache_sram);
+
+MODULE_AUTHOR("Wang Wenhu <wenhu.wang@vivo.com>");
+MODULE_DESCRIPTION("Freescale MPC85xx Cache-Sram UIO Platform Driver");
+MODULE_ALIAS("platform:" DRIVER_NAME);
+MODULE_LICENSE("GPL v2");
-- 
2.17.1

Re: [PATCH RESEND,v3,4/4] drivers: uio: new driver for fsl_85xx_cache_sram

[Christophe Leroy]

Le 16/04/2020 à 13:16, Wang Wenhu a écrit :
> A driver for freescale 85xx platforms to access the Cache-Sram form
> user level. This is extremely helpful for some user-space applications
> that require high performance memory accesses.
> 
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Christophe Leroy <christophe.leroy@c-s.fr>
> Cc: Scott Wood <oss@buserror.net>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> Cc: linuxppc-dev@lists.ozlabs.org
> Signed-off-by: Wang Wenhu <wenhu.wang@vivo.com>
> ---
> Changes since v1:
>   * Addressed comments from Greg K-H
>   * Moved kfree(info->name) into uio_info_free_internal()
> Changes since v2:
>   * Addressed comments from Greg, Scott and Christophe
>   * Use "uiomem->internal_addr" as if condition for sram memory free,
>     and memset the uiomem entry
>   * Modified of_match_table make the driver apart from Cache-Sram HW info
>     which belong to the HW level driver fsl_85xx_cache_sram to match
>   * Use roundup_pow_of_two for align calculation
>   * Remove useless clear block of uiomem entries.
>   * Use UIO_INFO_VER micro for info->version, and define it as
>     "devicetree,pseudo", meaning this is pseudo device and probed from
>     device tree configuration
>   * Select FSL_85XX_CACHE_SRAM rather than depends on it
> ---
>   drivers/uio/Kconfig                   |   9 ++
>   drivers/uio/Makefile                  |   1 +
>   drivers/uio/uio_fsl_85xx_cache_sram.c | 158 ++++++++++++++++++++++++++
>   3 files changed, 168 insertions(+)
>   create mode 100644 drivers/uio/uio_fsl_85xx_cache_sram.c
> 
> diff --git a/drivers/uio/Kconfig b/drivers/uio/Kconfig
> index 202ee81cfc2b..9c3b47461b71 100644
> --- a/drivers/uio/Kconfig
> +++ b/drivers/uio/Kconfig
> @@ -105,6 +105,15 @@ config UIO_NETX
>   	  To compile this driver as a module, choose M here; the module
>   	  will be called uio_netx.
>   
> +config UIO_FSL_85XX_CACHE_SRAM
> +	tristate "Freescale 85xx Cache-Sram driver"
> +	depends on FSL_SOC_BOOKE && PPC32
> +	select FSL_85XX_CACHE_SRAM
> +	help
> +	  Generic driver for accessing the Cache-Sram form user level. This
> +	  is extremely helpful for some user-space applications that require
> +	  high performance memory accesses.
> +
>   config UIO_FSL_ELBC_GPCM
>   	tristate "eLBC/GPCM driver"
>   	depends on FSL_LBC
> diff --git a/drivers/uio/Makefile b/drivers/uio/Makefile
> index c285dd2a4539..be2056cffc21 100644
> --- a/drivers/uio/Makefile
> +++ b/drivers/uio/Makefile
> @@ -10,4 +10,5 @@ obj-$(CONFIG_UIO_NETX)	+= uio_netx.o
>   obj-$(CONFIG_UIO_PRUSS)         += uio_pruss.o
>   obj-$(CONFIG_UIO_MF624)         += uio_mf624.o
>   obj-$(CONFIG_UIO_FSL_ELBC_GPCM)	+= uio_fsl_elbc_gpcm.o
> +obj-$(CONFIG_UIO_FSL_85XX_CACHE_SRAM)	+= uio_fsl_85xx_cache_sram.o
>   obj-$(CONFIG_UIO_HV_GENERIC)	+= uio_hv_generic.o
> diff --git a/drivers/uio/uio_fsl_85xx_cache_sram.c b/drivers/uio/uio_fsl_85xx_cache_sram.c
> new file mode 100644
> index 000000000000..8701df695307
> --- /dev/null
> +++ b/drivers/uio/uio_fsl_85xx_cache_sram.c
> @@ -0,0 +1,158 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2020 Vivo Communication Technology Co. Ltd.
> + * Copyright (C) 2020 Wang Wenhu <wenhu.wang@vivo.com>
> + * All rights reserved.
> + */
> +
> +#include <linux/platform_device.h>
> +#include <linux/uio_driver.h>
> +#include <linux/stringify.h>
> +#include <linux/module.h>
> +#include <linux/kernel.h>
> +#include <asm/fsl_85xx_cache_sram.h>
> +
> +#define DRIVER_NAME	"uio_fsl_85xx_cache_sram"
> +#define UIO_INFO_VER	"devicetree,pseudo"
> +#define UIO_NAME	"uio_cache_sram"
> +
> +static void uio_info_free_internal(struct uio_info *info)
> +{
> +	struct uio_mem *uiomem = info->mem;
> +
> +	while (uiomem < &info->mem[MAX_UIO_MAPS]) {

As suggested by Scott, maybe it would be better to use a loop with an 
index, something like

	for (i = 0; i < MAX_UIO_MAPS; i++, uiomem++) {
		struct uio_mem *uiomem = info->mem[i];

> +		if (uiomem->internal_addr) {
> +			mpc85xx_cache_sram_free(uiomem->internal_addr);
> +			kfree(uiomem->name);

Unneeded when using devm_kstrdup(), see in the probe function.

> +			memset(uiomem, 0, sizeof(*uiomem));
> +		}
> +		uiomem++;
> +	}
> +
> +	kfree(info->name);

That's a bit unbalanced. This function is handy for the things allocated 
inside the loop, but for the info->name allocated outside the loop, it 
should be released outside this function.

At the end if you use devm_kstrdup(), it will void anyway.

> +}
> +
> +static int uio_fsl_85xx_cache_sram_probe(struct platform_device *pdev)
> +{
> +	struct device_node *parent = pdev->dev.of_node;
> +	struct device_node *node = NULL;
> +	struct uio_info *info;
> +	struct uio_mem *uiomem;
> +	const char *dt_name;
> +	u32 mem_size;
> +	int ret;
> +
> +	/* alloc uio_info for one device */
> +	info = kzalloc(sizeof(*info), GFP_KERNEL);

Maybe use devm_kzalloc(). That way, it will be automatically freed when 
the driver is released, both a normal release and on probe failure.

> +	if (!info)
> +		return -ENOMEM;
> +
> +	/* get optional uio name */
> +	if (of_property_read_string(parent, "uio_name", &dt_name))
> +		dt_name = UIO_NAME;
> +
> +	info->name = kstrdup(dt_name, GFP_KERNEL);

Can use devm_kstrdup()

> +	if (!info->name) {
> +		ret = -ENOMEM;

If using devm_kzalloc(), you can then directly do return -ENOMEM, and 
the release will be automatic.

> +		goto err_info_free;
> +	}
> +
> +	uiomem = info->mem;
> +	for_each_child_of_node(parent, node) {
> +		void *virt;
> +		phys_addr_t phys;
> +
> +		ret = of_property_read_u32(node, "cache-mem-size", &mem_size);
> +		if (ret) {
> +			ret = -EINVAL;
> +			goto err_info_free_internal;
> +		}
> +
> +		if (mem_size == 0) {
> +			dev_err(&pdev->dev, "cache-mem-size should not be 0\n");
> +			ret = -EINVAL;
> +			goto err_info_free_internal;
> +		}
> +
> +		virt = mpc85xx_cache_sram_alloc(mem_size,
> +						&phys,

I think &phys can fit on first line.

> +						roundup_pow_of_two(mem_size));
> +		if (!virt) {
> +			/* mpc85xx_cache_sram_alloc to define the real cause */
> +			ret = -ENOMEM;
> +			goto err_info_free_internal;
> +		}
> +
> +		uiomem->memtype = UIO_MEM_PHYS;
> +		uiomem->addr = phys;
> +		uiomem->size = mem_size;
> +		uiomem->name = kstrdup(node->name, GFP_KERNEL);;

Use devm_kstrdup()

> +		uiomem->internal_addr = virt;
> +		uiomem++;
> +
> +		if (uiomem >= &info->mem[MAX_UIO_MAPS]) {
> +			dev_warn(&pdev->dev, "more than %d uio-maps for device.\n",
> +				 MAX_UIO_MAPS);
> +			break;
> +		}
> +	}
> +
> +	if (uiomem == info->mem) {
> +		dev_err(&pdev->dev, "error no valid uio-map configured\n");
> +		ret = -EINVAL;
> +		goto err_info_free_internal;

Is there anything to free up if nothing has been allocated ?

> +	}
> +
> +	info->version = UIO_INFO_VER;
> +
> +	/* register uio device */
> +	if (uio_register_device(&pdev->dev, info)) {
> +		dev_err(&pdev->dev, "uio registration failed\n");
> +		ret = -ENODEV;
> +		goto err_info_free_internal;
> +	}
> +
> +	platform_set_drvdata(pdev, info);
> +
> +	return 0;
> +err_info_free_internal:
> +	uio_info_free_internal(info);
> +err_info_free:
> +	kfree(info);

Shouldn't be needed when using devm_kzalloc().

> +	return ret;
> +}
> +
> +static int uio_fsl_85xx_cache_sram_remove(struct platform_device *pdev)
> +{
> +	struct uio_info *info = platform_get_drvdata(pdev);
> +
> +	uio_unregister_device(info);
> +
> +	uio_info_free_internal(info);
> +
> +	kfree(info);

Not needed when using dev_kzalloc()

> +
> +	return 0;
> +}
> +
> +static const struct of_device_id uio_mpc85xx_l2ctlr_of_match[] = {
> +	{	.compatible = "uio,mpc85xx-cache-sram",	},
> +	{},
> +};
> +
> +static struct platform_driver uio_fsl_85xx_cache_sram = {
> +	.probe = uio_fsl_85xx_cache_sram_probe,
> +	.remove = uio_fsl_85xx_cache_sram_remove,
> +	.driver = {
> +		.name = DRIVER_NAME,
> +		.owner = THIS_MODULE,
> +		.of_match_table	= uio_mpc85xx_l2ctlr_of_match,
> +	},
> +};
> +
> +module_platform_driver(uio_fsl_85xx_cache_sram);
> +
> +MODULE_AUTHOR("Wang Wenhu <wenhu.wang@vivo.com>");
> +MODULE_DESCRIPTION("Freescale MPC85xx Cache-Sram UIO Platform Driver");
> +MODULE_ALIAS("platform:" DRIVER_NAME);
> +MODULE_LICENSE("GPL v2");
> 

Christophe

Re: [PATCH RESEND,v3,4/4] drivers: uio: new driver for fsl_85xx_cache_sram

[Christophe Leroy]

Le 16/04/2020 à 13:16, Wang Wenhu a écrit :
> A driver for freescale 85xx platforms to access the Cache-Sram form
> user level. This is extremely helpful for some user-space applications
> that require high performance memory accesses.
> 
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Christophe Leroy <christophe.leroy@c-s.fr>
> Cc: Scott Wood <oss@buserror.net>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> Cc: linuxppc-dev@lists.ozlabs.org
> Signed-off-by: Wang Wenhu <wenhu.wang@vivo.com>
> ---
> Changes since v1:
>   * Addressed comments from Greg K-H
>   * Moved kfree(info->name) into uio_info_free_internal()
> Changes since v2:
>   * Addressed comments from Greg, Scott and Christophe
>   * Use "uiomem->internal_addr" as if condition for sram memory free,
>     and memset the uiomem entry
>   * Modified of_match_table make the driver apart from Cache-Sram HW info
>     which belong to the HW level driver fsl_85xx_cache_sram to match
>   * Use roundup_pow_of_two for align calculation
>   * Remove useless clear block of uiomem entries.
>   * Use UIO_INFO_VER micro for info->version, and define it as
>     "devicetree,pseudo", meaning this is pseudo device and probed from
>     device tree configuration
>   * Select FSL_85XX_CACHE_SRAM rather than depends on it
> ---
>   drivers/uio/Kconfig                   |   9 ++
>   drivers/uio/Makefile                  |   1 +
>   drivers/uio/uio_fsl_85xx_cache_sram.c | 158 ++++++++++++++++++++++++++
>   3 files changed, 168 insertions(+)
>   create mode 100644 drivers/uio/uio_fsl_85xx_cache_sram.c
> 
> diff --git a/drivers/uio/Kconfig b/drivers/uio/Kconfig
> index 202ee81cfc2b..9c3b47461b71 100644
> --- a/drivers/uio/Kconfig
> +++ b/drivers/uio/Kconfig
> @@ -105,6 +105,15 @@ config UIO_NETX
>   	  To compile this driver as a module, choose M here; the module
>   	  will be called uio_netx.
>   
> +config UIO_FSL_85XX_CACHE_SRAM
> +	tristate "Freescale 85xx Cache-Sram driver"
> +	depends on FSL_SOC_BOOKE && PPC32
> +	select FSL_85XX_CACHE_SRAM
> +	help
> +	  Generic driver for accessing the Cache-Sram form user level. This
> +	  is extremely helpful for some user-space applications that require
> +	  high performance memory accesses.
> +
>   config UIO_FSL_ELBC_GPCM
>   	tristate "eLBC/GPCM driver"
>   	depends on FSL_LBC
> diff --git a/drivers/uio/Makefile b/drivers/uio/Makefile
> index c285dd2a4539..be2056cffc21 100644
> --- a/drivers/uio/Makefile
> +++ b/drivers/uio/Makefile
> @@ -10,4 +10,5 @@ obj-$(CONFIG_UIO_NETX)	+= uio_netx.o
>   obj-$(CONFIG_UIO_PRUSS)         += uio_pruss.o
>   obj-$(CONFIG_UIO_MF624)         += uio_mf624.o
>   obj-$(CONFIG_UIO_FSL_ELBC_GPCM)	+= uio_fsl_elbc_gpcm.o
> +obj-$(CONFIG_UIO_FSL_85XX_CACHE_SRAM)	+= uio_fsl_85xx_cache_sram.o
>   obj-$(CONFIG_UIO_HV_GENERIC)	+= uio_hv_generic.o
> diff --git a/drivers/uio/uio_fsl_85xx_cache_sram.c b/drivers/uio/uio_fsl_85xx_cache_sram.c
> new file mode 100644
> index 000000000000..8701df695307
> --- /dev/null
> +++ b/drivers/uio/uio_fsl_85xx_cache_sram.c
> @@ -0,0 +1,158 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2020 Vivo Communication Technology Co. Ltd.
> + * Copyright (C) 2020 Wang Wenhu <wenhu.wang@vivo.com>
> + * All rights reserved.
> + */
> +
> +#include <linux/platform_device.h>
> +#include <linux/uio_driver.h>
> +#include <linux/stringify.h>
> +#include <linux/module.h>
> +#include <linux/kernel.h>
> +#include <asm/fsl_85xx_cache_sram.h>
> +
> +#define DRIVER_NAME	"uio_fsl_85xx_cache_sram"
> +#define UIO_INFO_VER	"devicetree,pseudo"
> +#define UIO_NAME	"uio_cache_sram"
> +
> +static void uio_info_free_internal(struct uio_info *info)
> +{
> +	struct uio_mem *uiomem = info->mem;
> +
> +	while (uiomem < &info->mem[MAX_UIO_MAPS]) {

As suggested by Scott, maybe it would be better to use a loop with an 
index, something like

	for (i = 0; i < MAX_UIO_MAPS; i++, uiomem++) {
		struct uio_mem *uiomem = info->mem[i];

> +		if (uiomem->internal_addr) {
> +			mpc85xx_cache_sram_free(uiomem->internal_addr);
> +			kfree(uiomem->name);

Unneeded when using devm_kstrdup(), see in the probe function.

> +			memset(uiomem, 0, sizeof(*uiomem));
> +		}
> +		uiomem++;
> +	}
> +
> +	kfree(info->name);

That's a bit unbalanced. This function is handy for the things allocated 
inside the loop, but for the info->name allocated outside the loop, it 
should be released outside this function.

At the end if you use devm_kstrdup(), it will void anyway.

> +}
> +
> +static int uio_fsl_85xx_cache_sram_probe(struct platform_device *pdev)
> +{
> +	struct device_node *parent = pdev->dev.of_node;
> +	struct device_node *node = NULL;
> +	struct uio_info *info;
> +	struct uio_mem *uiomem;
> +	const char *dt_name;
> +	u32 mem_size;
> +	int ret;
> +
> +	/* alloc uio_info for one device */
> +	info = kzalloc(sizeof(*info), GFP_KERNEL);

Maybe use devm_kzalloc(). That way, it will be automatically freed when 
the driver is released, both a normal release and on probe failure.

> +	if (!info)
> +		return -ENOMEM;
> +
> +	/* get optional uio name */
> +	if (of_property_read_string(parent, "uio_name", &dt_name))
> +		dt_name = UIO_NAME;
> +
> +	info->name = kstrdup(dt_name, GFP_KERNEL);

Can use devm_kstrdup()

> +	if (!info->name) {
> +		ret = -ENOMEM;

If using devm_kzalloc(), you can then directly do return -ENOMEM, and 
the release will be automatic.

> +		goto err_info_free;
> +	}
> +
> +	uiomem = info->mem;
> +	for_each_child_of_node(parent, node) {
> +		void *virt;
> +		phys_addr_t phys;
> +
> +		ret = of_property_read_u32(node, "cache-mem-size", &mem_size);
> +		if (ret) {
> +			ret = -EINVAL;
> +			goto err_info_free_internal;
> +		}
> +
> +		if (mem_size == 0) {
> +			dev_err(&pdev->dev, "cache-mem-size should not be 0\n");
> +			ret = -EINVAL;
> +			goto err_info_free_internal;
> +		}
> +
> +		virt = mpc85xx_cache_sram_alloc(mem_size,
> +						&phys,

I think &phys can fit on first line.

> +						roundup_pow_of_two(mem_size));
> +		if (!virt) {
> +			/* mpc85xx_cache_sram_alloc to define the real cause */
> +			ret = -ENOMEM;
> +			goto err_info_free_internal;
> +		}
> +
> +		uiomem->memtype = UIO_MEM_PHYS;
> +		uiomem->addr = phys;
> +		uiomem->size = mem_size;
> +		uiomem->name = kstrdup(node->name, GFP_KERNEL);;

Use devm_kstrdup()

> +		uiomem->internal_addr = virt;
> +		uiomem++;
> +
> +		if (uiomem >= &info->mem[MAX_UIO_MAPS]) {
> +			dev_warn(&pdev->dev, "more than %d uio-maps for device.\n",
> +				 MAX_UIO_MAPS);
> +			break;
> +		}
> +	}
> +
> +	if (uiomem == info->mem) {
> +		dev_err(&pdev->dev, "error no valid uio-map configured\n");
> +		ret = -EINVAL;
> +		goto err_info_free_internal;

Is there anything to free up if nothing has been allocated ?

> +	}
> +
> +	info->version = UIO_INFO_VER;
> +
> +	/* register uio device */
> +	if (uio_register_device(&pdev->dev, info)) {
> +		dev_err(&pdev->dev, "uio registration failed\n");
> +		ret = -ENODEV;
> +		goto err_info_free_internal;
> +	}
> +
> +	platform_set_drvdata(pdev, info);
> +
> +	return 0;
> +err_info_free_internal:
> +	uio_info_free_internal(info);
> +err_info_free:
> +	kfree(info);

Shouldn't be needed when using devm_kzalloc().

> +	return ret;
> +}
> +
> +static int uio_fsl_85xx_cache_sram_remove(struct platform_device *pdev)
> +{
> +	struct uio_info *info = platform_get_drvdata(pdev);
> +
> +	uio_unregister_device(info);
> +
> +	uio_info_free_internal(info);
> +
> +	kfree(info);

Not needed when using dev_kzalloc()

> +
> +	return 0;
> +}
> +
> +static const struct of_device_id uio_mpc85xx_l2ctlr_of_match[] = {
> +	{	.compatible = "uio,mpc85xx-cache-sram",	},
> +	{},
> +};
> +
> +static struct platform_driver uio_fsl_85xx_cache_sram = {
> +	.probe = uio_fsl_85xx_cache_sram_probe,
> +	.remove = uio_fsl_85xx_cache_sram_remove,
> +	.driver = {
> +		.name = DRIVER_NAME,
> +		.owner = THIS_MODULE,
> +		.of_match_table	= uio_mpc85xx_l2ctlr_of_match,
> +	},
> +};
> +
> +module_platform_driver(uio_fsl_85xx_cache_sram);
> +
> +MODULE_AUTHOR("Wang Wenhu <wenhu.wang@vivo.com>");
> +MODULE_DESCRIPTION("Freescale MPC85xx Cache-Sram UIO Platform Driver");
> +MODULE_ALIAS("platform:" DRIVER_NAME);
> +MODULE_LICENSE("GPL v2");
> 

Christophe

Re:Re: [PATCH RESEND,v3,4/4] drivers: uio: new driver for fsl_85xx_cache_sram

[王文虎]

Hi, Christophe,
dev_kzalloc really looks better. I will update the patch with the comments addressed.

Thanks,
Wenhu

From: Christophe Leroy <christophe.leroy@c-s.fr> Date: 2020-04-16 19:49:01
To:Wang Wenhu <wenhu.wang@vivo.com>,gregkh@linuxfoundation.org,
linux-kernel@vger.kernel.org,oss@buserror.net,linuxppc-dev@lists.ozlabs.org
 cc: kernel@vivo.com,Michael Ellerman <mpe@ellerman.id.au>
Subject: Re: [PATCH RESEND,v3,4/4] drivers: uio: new driver for fsl_85xx_cache_sram>
>
>Le 16/04/2020 à 13:16, Wang Wenhu a écrit :
>> A driver for freescale 85xx platforms to access the Cache-Sram form
>> user level. This is extremely helpful for some user-space applications
>> that require high performance memory accesses.
>> 
>> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> Cc: Christophe Leroy <christophe.leroy@c-s.fr>
>> Cc: Scott Wood <oss@buserror.net>
>> Cc: Michael Ellerman <mpe@ellerman.id.au>
>> Cc: linuxppc-dev@lists.ozlabs.org
>> Signed-off-by: Wang Wenhu <wenhu.wang@vivo.com>
>> ---
>> Changes since v1:
>>   * Addressed comments from Greg K-H
>>   * Moved kfree(info->name) into uio_info_free_internal()
>> Changes since v2:
>>   * Addressed comments from Greg, Scott and Christophe
>>   * Use "uiomem->internal_addr" as if condition for sram memory free,
>>     and memset the uiomem entry
>>   * Modified of_match_table make the driver apart from Cache-Sram HW info
>>     which belong to the HW level driver fsl_85xx_cache_sram to match
>>   * Use roundup_pow_of_two for align calculation
>>   * Remove useless clear block of uiomem entries.
>>   * Use UIO_INFO_VER micro for info->version, and define it as
>>     "devicetree,pseudo", meaning this is pseudo device and probed from
>>     device tree configuration
>>   * Select FSL_85XX_CACHE_SRAM rather than depends on it
>> ---
>>   drivers/uio/Kconfig                   |   9 ++
>>   drivers/uio/Makefile                  |   1 +
>>   drivers/uio/uio_fsl_85xx_cache_sram.c | 158 ++++++++++++++++++++++++++
>>   3 files changed, 168 insertions(+)
>>   create mode 100644 drivers/uio/uio_fsl_85xx_cache_sram.c
>> 
>> diff --git a/drivers/uio/Kconfig b/drivers/uio/Kconfig
>> index 202ee81cfc2b..9c3b47461b71 100644
>> --- a/drivers/uio/Kconfig
>> +++ b/drivers/uio/Kconfig
>> @@ -105,6 +105,15 @@ config UIO_NETX
>>   	  To compile this driver as a module, choose M here; the module
>>   	  will be called uio_netx.
>>   
>> +config UIO_FSL_85XX_CACHE_SRAM
>> +	tristate "Freescale 85xx Cache-Sram driver"
>> +	depends on FSL_SOC_BOOKE && PPC32
>> +	select FSL_85XX_CACHE_SRAM
>> +	help
>> +	  Generic driver for accessing the Cache-Sram form user level. This
>> +	  is extremely helpful for some user-space applications that require
>> +	  high performance memory accesses.
>> +
>>   config UIO_FSL_ELBC_GPCM
>>   	tristate "eLBC/GPCM driver"
>>   	depends on FSL_LBC
>> diff --git a/drivers/uio/Makefile b/drivers/uio/Makefile
>> index c285dd2a4539..be2056cffc21 100644
>> --- a/drivers/uio/Makefile
>> +++ b/drivers/uio/Makefile
>> @@ -10,4 +10,5 @@ obj-$(CONFIG_UIO_NETX)	+= uio_netx.o
>>   obj-$(CONFIG_UIO_PRUSS)         += uio_pruss.o
>>   obj-$(CONFIG_UIO_MF624)         += uio_mf624.o
>>   obj-$(CONFIG_UIO_FSL_ELBC_GPCM)	+= uio_fsl_elbc_gpcm.o
>> +obj-$(CONFIG_UIO_FSL_85XX_CACHE_SRAM)	+= uio_fsl_85xx_cache_sram.o
>>   obj-$(CONFIG_UIO_HV_GENERIC)	+= uio_hv_generic.o
>> diff --git a/drivers/uio/uio_fsl_85xx_cache_sram.c b/drivers/uio/uio_fsl_85xx_cache_sram.c
>> new file mode 100644
>> index 000000000000..8701df695307
>> --- /dev/null
>> +++ b/drivers/uio/uio_fsl_85xx_cache_sram.c
>> @@ -0,0 +1,158 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Copyright (C) 2020 Vivo Communication Technology Co. Ltd.
>> + * Copyright (C) 2020 Wang Wenhu <wenhu.wang@vivo.com>
>> + * All rights reserved.
>> + */
>> +
>> +#include <linux/platform_device.h>
>> +#include <linux/uio_driver.h>
>> +#include <linux/stringify.h>
>> +#include <linux/module.h>
>> +#include <linux/kernel.h>
>> +#include <asm/fsl_85xx_cache_sram.h>
>> +
>> +#define DRIVER_NAME	"uio_fsl_85xx_cache_sram"
>> +#define UIO_INFO_VER	"devicetree,pseudo"
>> +#define UIO_NAME	"uio_cache_sram"
>> +
>> +static void uio_info_free_internal(struct uio_info *info)
>> +{
>> +	struct uio_mem *uiomem = info->mem;
>> +
>> +	while (uiomem < &info->mem[MAX_UIO_MAPS]) {
>
>As suggested by Scott, maybe it would be better to use a loop with an 
>index, something like
>
>	for (i = 0; i < MAX_UIO_MAPS; i++, uiomem++) {
>		struct uio_mem *uiomem = info->mem[i];
>
>> +		if (uiomem->internal_addr) {
>> +			mpc85xx_cache_sram_free(uiomem->internal_addr);
>> +			kfree(uiomem->name);
>
>Unneeded when using devm_kstrdup(), see in the probe function.
>
>> +			memset(uiomem, 0, sizeof(*uiomem));
>> +		}
>> +		uiomem++;
>> +	}
>> +
>> +	kfree(info->name);
>
>That's a bit unbalanced. This function is handy for the things allocated 
>inside the loop, but for the info->name allocated outside the loop, it 
>should be released outside this function.
>
>At the end if you use devm_kstrdup(), it will void anyway.
>
>> +}
>> +
>> +static int uio_fsl_85xx_cache_sram_probe(struct platform_device *pdev)
>> +{
>> +	struct device_node *parent = pdev->dev.of_node;
>> +	struct device_node *node = NULL;
>> +	struct uio_info *info;
>> +	struct uio_mem *uiomem;
>> +	const char *dt_name;
>> +	u32 mem_size;
>> +	int ret;
>> +
>> +	/* alloc uio_info for one device */
>> +	info = kzalloc(sizeof(*info), GFP_KERNEL);
>
>Maybe use devm_kzalloc(). That way, it will be automatically freed when 
>the driver is released, both a normal release and on probe failure.
>
>> +	if (!info)
>> +		return -ENOMEM;
>> +
>> +	/* get optional uio name */
>> +	if (of_property_read_string(parent, "uio_name", &dt_name))
>> +		dt_name = UIO_NAME;
>> +
>> +	info->name = kstrdup(dt_name, GFP_KERNEL);
>
>Can use devm_kstrdup()
>
>> +	if (!info->name) {
>> +		ret = -ENOMEM;
>
>If using devm_kzalloc(), you can then directly do return -ENOMEM, and 
>the release will be automatic.
>
>> +		goto err_info_free;
>> +	}
>> +
>> +	uiomem = info->mem;
>> +	for_each_child_of_node(parent, node) {
>> +		void *virt;
>> +		phys_addr_t phys;
>> +
>> +		ret = of_property_read_u32(node, "cache-mem-size", &mem_size);
>> +		if (ret) {
>> +			ret = -EINVAL;
>> +			goto err_info_free_internal;
>> +		}
>> +
>> +		if (mem_size == 0) {
>> +			dev_err(&pdev->dev, "cache-mem-size should not be 0\n");
>> +			ret = -EINVAL;
>> +			goto err_info_free_internal;
>> +		}
>> +
>> +		virt = mpc85xx_cache_sram_alloc(mem_size,
>> +						&phys,
>
>I think &phys can fit on first line.
>
>> +						roundup_pow_of_two(mem_size));
>> +		if (!virt) {
>> +			/* mpc85xx_cache_sram_alloc to define the real cause */
>> +			ret = -ENOMEM;
>> +			goto err_info_free_internal;
>> +		}
>> +
>> +		uiomem->memtype = UIO_MEM_PHYS;
>> +		uiomem->addr = phys;
>> +		uiomem->size = mem_size;
>> +		uiomem->name = kstrdup(node->name, GFP_KERNEL);;
>
>Use devm_kstrdup()
>
>> +		uiomem->internal_addr = virt;
>> +		uiomem++;
>> +
>> +		if (uiomem >= &info->mem[MAX_UIO_MAPS]) {
>> +			dev_warn(&pdev->dev, "more than %d uio-maps for device.\n",
>> +				 MAX_UIO_MAPS);
>> +			break;
>> +		}
>> +	}
>> +
>> +	if (uiomem == info->mem) {
>> +		dev_err(&pdev->dev, "error no valid uio-map configured\n");
>> +		ret = -EINVAL;
>> +		goto err_info_free_internal;
>
>Is there anything to free up if nothing has been allocated ?
>
>> +	}
>> +
>> +	info->version = UIO_INFO_VER;
>> +
>> +	/* register uio device */
>> +	if (uio_register_device(&pdev->dev, info)) {
>> +		dev_err(&pdev->dev, "uio registration failed\n");
>> +		ret = -ENODEV;
>> +		goto err_info_free_internal;
>> +	}
>> +
>> +	platform_set_drvdata(pdev, info);
>> +
>> +	return 0;
>> +err_info_free_internal:
>> +	uio_info_free_internal(info);
>> +err_info_free:
>> +	kfree(info);
>
>Shouldn't be needed when using devm_kzalloc().
>
>> +	return ret;
>> +}
>> +
>> +static int uio_fsl_85xx_cache_sram_remove(struct platform_device *pdev)
>> +{
>> +	struct uio_info *info = platform_get_drvdata(pdev);
>> +
>> +	uio_unregister_device(info);
>> +
>> +	uio_info_free_internal(info);
>> +
>> +	kfree(info);
>
>Not needed when using dev_kzalloc()
>
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct of_device_id uio_mpc85xx_l2ctlr_of_match[] = {
>> +	{	.compatible = "uio,mpc85xx-cache-sram",	},
>> +	{},
>> +};
>> +
>> +static struct platform_driver uio_fsl_85xx_cache_sram = {
>> +	.probe = uio_fsl_85xx_cache_sram_probe,
>> +	.remove = uio_fsl_85xx_cache_sram_remove,
>> +	.driver = {
>> +		.name = DRIVER_NAME,
>> +		.owner = THIS_MODULE,
>> +		.of_match_table	= uio_mpc85xx_l2ctlr_of_match,
>> +	},
>> +};
>> +
>> +module_platform_driver(uio_fsl_85xx_cache_sram);
>> +
>> +MODULE_AUTHOR("Wang Wenhu <wenhu.wang@vivo.com>");
>> +MODULE_DESCRIPTION("Freescale MPC85xx Cache-Sram UIO Platform Driver");
>> +MODULE_ALIAS("platform:" DRIVER_NAME);
>> +MODULE_LICENSE("GPL v2");
>> 
>
>Christophe

Re:Re: [PATCH RESEND,v3,4/4] drivers: uio: new driver for fsl_85xx_cache_sram

[王文虎]

Hi, Christophe,
dev_kzalloc really looks better. I will update the patch with the comments addressed.

Thanks,
Wenhu

From: Christophe Leroy <christophe.leroy@c-s.fr> Date: 2020-04-16 19:49:01
To:Wang Wenhu <wenhu.wang@vivo.com>,gregkh@linuxfoundation.org,
linux-kernel@vger.kernel.org,oss@buserror.net,linuxppc-dev@lists.ozlabs.org
 cc: kernel@vivo.com,Michael Ellerman <mpe@ellerman.id.au>
Subject: Re: [PATCH RESEND,v3,4/4] drivers: uio: new driver for fsl_85xx_cache_sram>
>
>Le 16/04/2020 à 13:16, Wang Wenhu a écrit :
>> A driver for freescale 85xx platforms to access the Cache-Sram form
>> user level. This is extremely helpful for some user-space applications
>> that require high performance memory accesses.
>> 
>> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> Cc: Christophe Leroy <christophe.leroy@c-s.fr>
>> Cc: Scott Wood <oss@buserror.net>
>> Cc: Michael Ellerman <mpe@ellerman.id.au>
>> Cc: linuxppc-dev@lists.ozlabs.org
>> Signed-off-by: Wang Wenhu <wenhu.wang@vivo.com>
>> ---
>> Changes since v1:
>>   * Addressed comments from Greg K-H
>>   * Moved kfree(info->name) into uio_info_free_internal()
>> Changes since v2:
>>   * Addressed comments from Greg, Scott and Christophe
>>   * Use "uiomem->internal_addr" as if condition for sram memory free,
>>     and memset the uiomem entry
>>   * Modified of_match_table make the driver apart from Cache-Sram HW info
>>     which belong to the HW level driver fsl_85xx_cache_sram to match
>>   * Use roundup_pow_of_two for align calculation
>>   * Remove useless clear block of uiomem entries.
>>   * Use UIO_INFO_VER micro for info->version, and define it as
>>     "devicetree,pseudo", meaning this is pseudo device and probed from
>>     device tree configuration
>>   * Select FSL_85XX_CACHE_SRAM rather than depends on it
>> ---
>>   drivers/uio/Kconfig                   |   9 ++
>>   drivers/uio/Makefile                  |   1 +
>>   drivers/uio/uio_fsl_85xx_cache_sram.c | 158 ++++++++++++++++++++++++++
>>   3 files changed, 168 insertions(+)
>>   create mode 100644 drivers/uio/uio_fsl_85xx_cache_sram.c
>> 
>> diff --git a/drivers/uio/Kconfig b/drivers/uio/Kconfig
>> index 202ee81cfc2b..9c3b47461b71 100644
>> --- a/drivers/uio/Kconfig
>> +++ b/drivers/uio/Kconfig
>> @@ -105,6 +105,15 @@ config UIO_NETX
>>   	  To compile this driver as a module, choose M here; the module
>>   	  will be called uio_netx.
>>   
>> +config UIO_FSL_85XX_CACHE_SRAM
>> +	tristate "Freescale 85xx Cache-Sram driver"
>> +	depends on FSL_SOC_BOOKE && PPC32
>> +	select FSL_85XX_CACHE_SRAM
>> +	help
>> +	  Generic driver for accessing the Cache-Sram form user level. This
>> +	  is extremely helpful for some user-space applications that require
>> +	  high performance memory accesses.
>> +
>>   config UIO_FSL_ELBC_GPCM
>>   	tristate "eLBC/GPCM driver"
>>   	depends on FSL_LBC
>> diff --git a/drivers/uio/Makefile b/drivers/uio/Makefile
>> index c285dd2a4539..be2056cffc21 100644
>> --- a/drivers/uio/Makefile
>> +++ b/drivers/uio/Makefile
>> @@ -10,4 +10,5 @@ obj-$(CONFIG_UIO_NETX)	+= uio_netx.o
>>   obj-$(CONFIG_UIO_PRUSS)         += uio_pruss.o
>>   obj-$(CONFIG_UIO_MF624)         += uio_mf624.o
>>   obj-$(CONFIG_UIO_FSL_ELBC_GPCM)	+= uio_fsl_elbc_gpcm.o
>> +obj-$(CONFIG_UIO_FSL_85XX_CACHE_SRAM)	+= uio_fsl_85xx_cache_sram.o
>>   obj-$(CONFIG_UIO_HV_GENERIC)	+= uio_hv_generic.o
>> diff --git a/drivers/uio/uio_fsl_85xx_cache_sram.c b/drivers/uio/uio_fsl_85xx_cache_sram.c
>> new file mode 100644
>> index 000000000000..8701df695307
>> --- /dev/null
>> +++ b/drivers/uio/uio_fsl_85xx_cache_sram.c
>> @@ -0,0 +1,158 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Copyright (C) 2020 Vivo Communication Technology Co. Ltd.
>> + * Copyright (C) 2020 Wang Wenhu <wenhu.wang@vivo.com>
>> + * All rights reserved.
>> + */
>> +
>> +#include <linux/platform_device.h>
>> +#include <linux/uio_driver.h>
>> +#include <linux/stringify.h>
>> +#include <linux/module.h>
>> +#include <linux/kernel.h>
>> +#include <asm/fsl_85xx_cache_sram.h>
>> +
>> +#define DRIVER_NAME	"uio_fsl_85xx_cache_sram"
>> +#define UIO_INFO_VER	"devicetree,pseudo"
>> +#define UIO_NAME	"uio_cache_sram"
>> +
>> +static void uio_info_free_internal(struct uio_info *info)
>> +{
>> +	struct uio_mem *uiomem = info->mem;
>> +
>> +	while (uiomem < &info->mem[MAX_UIO_MAPS]) {
>
>As suggested by Scott, maybe it would be better to use a loop with an 
>index, something like
>
>	for (i = 0; i < MAX_UIO_MAPS; i++, uiomem++) {
>		struct uio_mem *uiomem = info->mem[i];
>
>> +		if (uiomem->internal_addr) {
>> +			mpc85xx_cache_sram_free(uiomem->internal_addr);
>> +			kfree(uiomem->name);
>
>Unneeded when using devm_kstrdup(), see in the probe function.
>
>> +			memset(uiomem, 0, sizeof(*uiomem));
>> +		}
>> +		uiomem++;
>> +	}
>> +
>> +	kfree(info->name);
>
>That's a bit unbalanced. This function is handy for the things allocated 
>inside the loop, but for the info->name allocated outside the loop, it 
>should be released outside this function.
>
>At the end if you use devm_kstrdup(), it will void anyway.
>
>> +}
>> +
>> +static int uio_fsl_85xx_cache_sram_probe(struct platform_device *pdev)
>> +{
>> +	struct device_node *parent = pdev->dev.of_node;
>> +	struct device_node *node = NULL;
>> +	struct uio_info *info;
>> +	struct uio_mem *uiomem;
>> +	const char *dt_name;
>> +	u32 mem_size;
>> +	int ret;
>> +
>> +	/* alloc uio_info for one device */
>> +	info = kzalloc(sizeof(*info), GFP_KERNEL);
>
>Maybe use devm_kzalloc(). That way, it will be automatically freed when 
>the driver is released, both a normal release and on probe failure.
>
>> +	if (!info)
>> +		return -ENOMEM;
>> +
>> +	/* get optional uio name */
>> +	if (of_property_read_string(parent, "uio_name", &dt_name))
>> +		dt_name = UIO_NAME;
>> +
>> +	info->name = kstrdup(dt_name, GFP_KERNEL);
>
>Can use devm_kstrdup()
>
>> +	if (!info->name) {
>> +		ret = -ENOMEM;
>
>If using devm_kzalloc(), you can then directly do return -ENOMEM, and 
>the release will be automatic.
>
>> +		goto err_info_free;
>> +	}
>> +
>> +	uiomem = info->mem;
>> +	for_each_child_of_node(parent, node) {
>> +		void *virt;
>> +		phys_addr_t phys;
>> +
>> +		ret = of_property_read_u32(node, "cache-mem-size", &mem_size);
>> +		if (ret) {
>> +			ret = -EINVAL;
>> +			goto err_info_free_internal;
>> +		}
>> +
>> +		if (mem_size == 0) {
>> +			dev_err(&pdev->dev, "cache-mem-size should not be 0\n");
>> +			ret = -EINVAL;
>> +			goto err_info_free_internal;
>> +		}
>> +
>> +		virt = mpc85xx_cache_sram_alloc(mem_size,
>> +						&phys,
>
>I think &phys can fit on first line.
>
>> +						roundup_pow_of_two(mem_size));
>> +		if (!virt) {
>> +			/* mpc85xx_cache_sram_alloc to define the real cause */
>> +			ret = -ENOMEM;
>> +			goto err_info_free_internal;
>> +		}
>> +
>> +		uiomem->memtype = UIO_MEM_PHYS;
>> +		uiomem->addr = phys;
>> +		uiomem->size = mem_size;
>> +		uiomem->name = kstrdup(node->name, GFP_KERNEL);;
>
>Use devm_kstrdup()
>
>> +		uiomem->internal_addr = virt;
>> +		uiomem++;
>> +
>> +		if (uiomem >= &info->mem[MAX_UIO_MAPS]) {
>> +			dev_warn(&pdev->dev, "more than %d uio-maps for device.\n",
>> +				 MAX_UIO_MAPS);
>> +			break;
>> +		}
>> +	}
>> +
>> +	if (uiomem == info->mem) {
>> +		dev_err(&pdev->dev, "error no valid uio-map configured\n");
>> +		ret = -EINVAL;
>> +		goto err_info_free_internal;
>
>Is there anything to free up if nothing has been allocated ?
>
>> +	}
>> +
>> +	info->version = UIO_INFO_VER;
>> +
>> +	/* register uio device */
>> +	if (uio_register_device(&pdev->dev, info)) {
>> +		dev_err(&pdev->dev, "uio registration failed\n");
>> +		ret = -ENODEV;
>> +		goto err_info_free_internal;
>> +	}
>> +
>> +	platform_set_drvdata(pdev, info);
>> +
>> +	return 0;
>> +err_info_free_internal:
>> +	uio_info_free_internal(info);
>> +err_info_free:
>> +	kfree(info);
>
>Shouldn't be needed when using devm_kzalloc().
>
>> +	return ret;
>> +}
>> +
>> +static int uio_fsl_85xx_cache_sram_remove(struct platform_device *pdev)
>> +{
>> +	struct uio_info *info = platform_get_drvdata(pdev);
>> +
>> +	uio_unregister_device(info);
>> +
>> +	uio_info_free_internal(info);
>> +
>> +	kfree(info);
>
>Not needed when using dev_kzalloc()
>
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct of_device_id uio_mpc85xx_l2ctlr_of_match[] = {
>> +	{	.compatible = "uio,mpc85xx-cache-sram",	},
>> +	{},
>> +};
>> +
>> +static struct platform_driver uio_fsl_85xx_cache_sram = {
>> +	.probe = uio_fsl_85xx_cache_sram_probe,
>> +	.remove = uio_fsl_85xx_cache_sram_remove,
>> +	.driver = {
>> +		.name = DRIVER_NAME,
>> +		.owner = THIS_MODULE,
>> +		.of_match_table	= uio_mpc85xx_l2ctlr_of_match,
>> +	},
>> +};
>> +
>> +module_platform_driver(uio_fsl_85xx_cache_sram);
>> +
>> +MODULE_AUTHOR("Wang Wenhu <wenhu.wang@vivo.com>");
>> +MODULE_DESCRIPTION("Freescale MPC85xx Cache-Sram UIO Platform Driver");
>> +MODULE_ALIAS("platform:" DRIVER_NAME);
>> +MODULE_LICENSE("GPL v2");
>> 
>
>Christophe