[PATCH] ARM: mach-shmobile: sh7372 A3RV power domain prototype

[PATCH] ARM: mach-shmobile: sh7372 A3RV power domain prototype

[Magnus Damm]

From: Magnus Damm <damm@opensource.se>

This somewhat messy prototype patch adds A3RV power domain
control support for sh7372. The A3RV power domain contains
the VPU video encoder/decoder which is exported through UIO.

The prototype serves as an example of a simple power domain
that needs to be turned off during boot. The default setting
after hardware reset is to keep A3RV powered on. The UIO driver
uio_pdrv_genirq.c does not access the VPU hardware at ->probe()
time but instead relies 100% on user space. So the VPU device
and A3RV will always be unused during boot.

Signed-off-by: Magnus Damm <damm@opensource.se>
---

 Applies to suspend-2.6.git pm-domains as of a few days ago:

 commit 6232eb8f755b0eb1a47f6fd6277da879248aba5e
 Author: Rafael J. Wysocki <rjw@sisk.pl>
 Date:   Wed Jun 22 02:20:43 2011 +0200

    ARM / shmobile: Support for I/O power domains for SH7372 (v7)

 arch/arm/mach-shmobile/board-mackerel.c      |    1 -
 arch/arm/mach-shmobile/include/mach/sh7372.h |    3 +++
 arch/arm/mach-shmobile/pm-sh7372.c           |    4 ++++
 arch/arm/mach-shmobile/setup-sh7372.c        |    5 +++++
 4 files changed, 12 insertions(+), 1 deletion(-)

--- 0001/arch/arm/mach-shmobile/board-mackerel.c
+++ work/arch/arm/mach-shmobile/board-mackerel.c	2011-06-22 21:19:13.000000000 +0900
@@ -1582,7 +1582,6 @@ static void __init mackerel_init(void)
 
 	platform_add_devices(mackerel_devices, ARRAY_SIZE(mackerel_devices));
 
-	sh7372_init_pm_domain(&sh7372_a4lc_domain);
 	sh7372_add_device_to_domain(SH7372_A4LC, &lcdc_device);
 	sh7372_add_device_to_domain(SH7372_A4LC, &hdmi_lcdc_device);
 
--- 0001/arch/arm/mach-shmobile/include/mach/sh7372.h
+++ work/arch/arm/mach-shmobile/include/mach/sh7372.h	2011-06-22 21:18:26.000000000 +0900
@@ -485,13 +485,16 @@ static inline struct sh7372_pm_domain *t
 
 #ifdef CONFIG_PM
 extern struct sh7372_pm_domain sh7372_a4lc_domain;
+extern struct sh7372_pm_domain sh7372_a3rv_domain;
 #define SH7372_A4LC	(&sh7372_a4lc_domain)
+#define SH7372_A3RV	(&sh7372_a3rv_domain)
 
 extern void sh7372_init_pm_domain(struct sh7372_pm_domain *sh7372_pd);
 extern void sh7372_add_device_to_domain(struct sh7372_pm_domain *sh7372_pd,
 					struct platform_device *pdev);
 #else
 #define SH7372_A4LC	NULL
+#define SH7372_A3RV	NULL
 
 static inline void sh7372_init_pm_domain(struct sh7372_pm_domain *sh7372_pd) {}
 static inline void sh7372_add_device_to_domain(struct sh7372_pm_domain *pd,
--- 0001/arch/arm/mach-shmobile/pm-sh7372.c
+++ work/arch/arm/mach-shmobile/pm-sh7372.c	2011-06-22 21:30:44.000000000 +0900
@@ -117,6 +117,10 @@ struct sh7372_pm_domain sh7372_a4lc_doma
 	.bit_shift = 1,
 };
 
+struct sh7372_pm_domain sh7372_a3rv_domain = {
+	.bit_shift = 6,
+};
+
 static void sh7372_enter_core_standby(void)
 {
 	void __iomem *smfram = (void __iomem *)SMFRAM;
--- 0001/arch/arm/mach-shmobile/setup-sh7372.c
+++ work/arch/arm/mach-shmobile/setup-sh7372.c	2011-06-22 21:24:03.000000000 +0900
@@ -841,11 +841,16 @@ static struct platform_device *sh7372_la
 
 void __init sh7372_add_standard_devices(void)
 {
+	sh7372_init_pm_domain(SH7372_A4LC);
+	sh7372_init_pm_domain(SH7372_A3RV);
+
 	platform_add_devices(sh7372_early_devices,
 			    ARRAY_SIZE(sh7372_early_devices));
 
 	platform_add_devices(sh7372_late_devices,
 			    ARRAY_SIZE(sh7372_late_devices));
+
+	sh7372_add_device_to_domain(SH7372_A3RV, &vpu_device);
 }
 
 void __init sh7372_add_early_devices(void)

Re: [PATCH] ARM: mach-shmobile: sh7372 A3RV power domain prototype

[Magnus Damm]

[-- Attachment #1: Type: text/plain, Size: 1254 bytes --]

On Fri, Jun 24, 2011 at 3:02 PM, Magnus Damm <magnus.damm@gmail.com> wrote:
> From: Magnus Damm <damm@opensource.se>
>
> This somewhat messy prototype patch adds A3RV power domain
> control support for sh7372. The A3RV power domain contains
> the VPU video encoder/decoder which is exported through UIO.
>
> The prototype serves as an example of a simple power domain
> that needs to be turned off during boot. The default setting
> after hardware reset is to keep A3RV powered on. The UIO driver
> uio_pdrv_genirq.c does not access the VPU hardware at ->probe()
> time but instead relies 100% on user space. So the VPU device
> and A3RV will always be unused during boot.

Also, people may want to use the attached test program to give this a go.

Without this patch, when "vpu-test" is executed twice then the second
run will produce this message:
"VPU5HG state kept since last open"
The message above is outputted when the state of a certain VPU
register is kept over UIO close->open.

With this patch applied the state of the VPU is always lost between
the UIO close->open, so the above message will never appear - at least
until there is a governor in place that prevents the power from being
turned off based on QoS information.

Cheers,

/ magnus

[-- Attachment #2: vpu-test-20110622.c --]
[-- Type: text/x-csrc, Size: 4223 bytes --]

/*
 * vpu-test - AP4 VPU test program, 20110622 Magnus Damm
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <fcntl.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <unistd.h>

static int fgets_with_openclose(char *fname, char *buf, size_t maxlen) {
       FILE *fp;

       if ((fp = fopen(fname, "r")) != NULL) {
               fgets(buf, maxlen, fp);
               fclose(fp);
               return strlen(buf);
       } else {
               return -1;
       }
}

struct uio_device {
       char *name;
       char *path;
       int fd;
};

#define MAXUIOIDS  100
#define MAXNAMELEN 256

static int locate_uio_device(char *name, struct uio_device *udp)
{
       char fname[MAXNAMELEN], buf[MAXNAMELEN];
       int uio_id, i;

       for (uio_id = 0; uio_id < MAXUIOIDS; uio_id++) {
               sprintf(fname, "/sys/class/uio/uio%d/name", uio_id);
               if (fgets_with_openclose(fname, buf, MAXNAMELEN) < 0)
                       continue;
               if (strncmp(name, buf, strlen(name)) == 0)
                       break;
       }

       if (uio_id >= MAXUIOIDS)
               return -1;

       udp->name = strdup(buf);
       udp->path = strdup(fname);
       udp->path[strlen(udp->path) - 4] = '\0';

       sprintf(buf, "/dev/uio%d", uio_id);
       udp->fd = open(buf, O_RDWR|O_SYNC /*| O_NONBLOCK*/);

       if (udp->fd < 0) {
               perror("open");
               return -1;
       }

       return 0;
}

struct uio_map {
       unsigned long address;
       unsigned long size;
       void *iomem;
};

static int setup_uio_map(struct uio_device *udp, int nr, struct uio_map *ump)
{
       char fname[MAXNAMELEN], buf[MAXNAMELEN];
 
       sprintf(fname, "%s/maps/map%d/addr", udp->path, nr);
       if (fgets_with_openclose(fname, buf, MAXNAMELEN) <= 0)
               return -1;

       ump->address = strtoul(buf, NULL, 0);

       sprintf(fname, "%s/maps/map%d/size", udp->path, nr);
       if (fgets_with_openclose(fname, buf, MAXNAMELEN) <= 0)
               return -1;

       ump->size = strtoul(buf, NULL, 0);

       ump->iomem = mmap(0, ump->size,
                         PROT_READ|PROT_WRITE, MAP_SHARED,
                         udp->fd, nr * getpagesize());

       if (ump->iomem == MAP_FAILED)
               return -1;

       return 0;
}

struct uio_device uio_dev;
struct uio_map uio_mmio;

int main(int argc, char *argv[])
{
	int ret;

	ret = locate_uio_device("VPU5HG", &uio_dev);
	if (ret < 0) {
		fprintf(stderr, "unable to locate UIO device\n");
		return 1;
	}
       
	ret = setup_uio_map(&uio_dev, 0, &uio_mmio);
	if (ret < 0) {
		fprintf(stderr, "unable to setup UIO memory map\n");
		return 1;
	}

	{
		unsigned long *ph = (uio_mmio.iomem + 0x00); /* VCRH */
		unsigned long *pl = (uio_mmio.iomem + 0x04); /* VCRL */
		unsigned long *pc = (uio_mmio.iomem + 0x08); /* CMD */
		unsigned long *pm = (uio_mmio.iomem + 0x80); /* MBA */
		int k;

		if ((*ph & 0xffff) == 0x55f4) {
			printf("detected VPU5HG with VCRH:VCRL 0x%08lx:%08lx\n",
			       *ph, *pl);

			if (*pm == 0xdeadbeef) {
				printf("VPU5HG state kept since last open\n");
			}

			*pc = 1 << 10; /* set MRST bit to force reset */
			for (k = 0; k < 5; k++) {
				if (!(*pc & (1 << 10))) {
					printf("VPU5HG reset check OK\n");
					*pm = 0xdeadbeef;
					printf("Sleeping 5 seconds...\n");
					sleep(5);
					return 0;
				}
				sleep(1);
			}
		}
	}

	fprintf(stderr, "unable to detect/reset VPU5HG\n");
	return 1;
}