Patchwork [U-Boot,15/17] Add console command to access io space registers

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Submitter Simon Glass
Date Nov. 3, 2012, 12:27 a.m.
Message ID <1351902453-27956-16-git-send-email-sjg@chromium.org>
Download mbox | patch
Permalink /patch/196787/
State Superseded, archived
Delegated to: Tom Rini
Headers show

Comments

Simon Glass - Nov. 3, 2012, 12:27 a.m.
From: Vadim Bendebury <vbendeb@chromium.org>

Provide u-boot console functions to access IO space registers. A no
thrills implementation, accessing one register at a time.

For example:
    boot > iod 80
    0080: 00000094
    boot > iod.w 80
    0080: 0094
    boot > iod.b 80
    0080: 94
    boot > iow.b 0x80 12
    boot > iod 0x80
    0080: 00000012

Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
---
 common/Makefile          |    1 +
 common/cmd_io.c          |   93 ++++++++++++++++++++++++++++++++++++++++++++++
 include/command.h        |    8 ++--
 include/config_cmd_all.h |    2 +
 4 files changed, 100 insertions(+), 4 deletions(-)
 create mode 100644 common/cmd_io.c
Wolfgang Denk - Nov. 3, 2012, 3:26 p.m.
Dear Simon Glass,

In message <1351902453-27956-16-git-send-email-sjg@chromium.org> you wrote:
> From: Vadim Bendebury <vbendeb@chromium.org>
> 
> Provide u-boot console functions to access IO space registers. A no
> thrills implementation, accessing one register at a time.
> 
> For example:
>     boot > iod 80
>     0080: 00000094
>     boot > iod.w 80
>     0080: 0094
>     boot > iod.b 80
>     0080: 94
>     boot > iow.b 0x80 12
>     boot > iod 0x80
>     0080: 00000012

What are the exact use cases where this is necessary, i. e. where
plain md / mw does not work?

Best regards,

Wolfgang Denk
Vadim Bendebury - Nov. 15, 2012, 11:28 p.m.
On Sat, Nov 3, 2012 at 8:26 AM, Wolfgang Denk <wd@denx.de> wrote:

> Dear Simon Glass,
>
> In message <1351902453-27956-16-git-send-email-sjg@chromium.org> you
> wrote:
> > From: Vadim Bendebury <vbendeb@chromium.org>
> >
> > Provide u-boot console functions to access IO space registers. A no
> > thrills implementation, accessing one register at a time.
> >
> > For example:
> >     boot > iod 80
> >     0080: 00000094
> >     boot > iod.w 80
> >     0080: 0094
> >     boot > iod.b 80
> >     0080: 94
> >     boot > iow.b 0x80 12
> >     boot > iod 0x80
> >     0080: 00000012
>
> What are the exact use cases where this is necessary, i. e. where
> plain md / mw does not work?
>
>
Wolfgang,

the x86 architecture defines this different kind of address space, device
IO, in addition to memory address space. This is a remnant of the days when
address lines were sparse.

On typical x86 systems devices are accessed through this device IO space,
and this patch adds a command which allows the operator to read and write
device registers on such systems.

Cheers,
/vb

Best regards,
>
> Wolfgang Denk
>
> --
> DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
> HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
> Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de
> Quantum particles: The dreams that stuff is made of.
> _______________________________________________
> U-Boot mailing list
> U-Boot@lists.denx.de
> http://lists.denx.de/mailman/listinfo/u-boot
>

Patch

diff --git a/common/Makefile b/common/Makefile
index eac38fc..d8cdca1 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -119,6 +119,7 @@  COBJS-$(CONFIG_LOGBUFFER) += cmd_log.o
 COBJS-$(CONFIG_ID_EEPROM) += cmd_mac.o
 COBJS-$(CONFIG_CMD_MD5SUM) += cmd_md5sum.o
 COBJS-$(CONFIG_CMD_MEMORY) += cmd_mem.o
+COBJS-$(CONFIG_CMD_IO) += cmd_io.o
 COBJS-$(CONFIG_CMD_MFSL) += cmd_mfsl.o
 COBJS-$(CONFIG_MII) += miiphyutil.o
 COBJS-$(CONFIG_CMD_MII) += miiphyutil.o
diff --git a/common/cmd_io.c b/common/cmd_io.c
new file mode 100644
index 0000000..6450cb5
--- /dev/null
+++ b/common/cmd_io.c
@@ -0,0 +1,93 @@ 
+/*
+ * Copyright (c) 2012 The Chromium OS Authors.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+/*
+ * IO space access commands.
+ */
+
+#include <common.h>
+#include <command.h>
+#include <asm/io.h>
+
+/*
+ * IO Display
+ *
+ * Syntax:
+ *	iod{.b, .w, .l} {addr}
+ */
+int do_io_iod(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
+{
+	ulong addr;
+	int size;
+
+	if (argc != 2)
+		return CMD_RET_USAGE;
+
+	size = cmd_get_data_size(argv[0], 4);
+	if (size < 0)
+		return 1;
+
+	addr = simple_strtoul(argv[1], NULL, 16);
+
+	printf("%04x: ", (u16) addr);
+
+	if (size == 4)
+		printf("%08x\n", inl(addr));
+	else if (size == 2)
+		printf("%04x\n", inw(addr));
+	else
+		printf("%02x\n", inb(addr));
+
+	return 0;
+}
+
+int do_io_iow(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
+{
+	ulong addr, size, val;
+
+	if (argc != 3)
+		return CMD_RET_USAGE;
+
+	size = cmd_get_data_size(argv[0], 4);
+	if (size < 0)
+		return 1;
+
+	addr = simple_strtoul(argv[1], NULL, 16);
+	val = simple_strtoul(argv[2], NULL, 16);
+
+	if (size == 4)
+		outl((u32) val, addr);
+	else if (size == 2)
+		outw((u16) val, addr);
+	else
+		outb((u8) val, addr);
+
+	return 0;
+}
+
+/**************************************************/
+U_BOOT_CMD(iod, 2, 0, do_io_iod,
+	   "IO space display", "[.b, .w, .l] address [# of objects]");
+
+U_BOOT_CMD(iow, 3, 0, do_io_iow,
+	   "IO space modify (auto-incrementing address)",
+	   "[.b, .w, .l] address");
diff --git a/include/command.h b/include/command.h
index 10bc260..476e7cf 100644
--- a/include/command.h
+++ b/include/command.h
@@ -89,10 +89,10 @@  extern int cmd_auto_complete(const char *const prompt, char *buf, int *np, int *
  */
 
 #if defined(CONFIG_CMD_MEMORY)		\
-    || defined(CONFIG_CMD_I2C)		\
-    || defined(CONFIG_CMD_ITEST)	\
-    || defined(CONFIG_CMD_PCI)		\
-    || defined(CONFIG_CMD_PORTIO)
+	|| defined(CONFIG_CMD_I2C)	\
+	|| defined(CONFIG_CMD_ITEST)	\
+	|| defined(CONFIG_CMD_PCI)	\
+	|| defined(CONFIG_CMD_PORTIO)
 #define CMD_DATA_SIZE
 extern int cmd_get_data_size(char* arg, int default_size);
 #endif
diff --git a/include/config_cmd_all.h b/include/config_cmd_all.h
index efd17e6..500b5cd 100644
--- a/include/config_cmd_all.h
+++ b/include/config_cmd_all.h
@@ -42,11 +42,13 @@ 
 #define CONFIG_CMD_FPGA		/* FPGA configuration Support	*/
 #define CONFIG_CMD_GETTIME	/* Get time since boot         */
 #define CONFIG_CMD_HWFLOW	/* RTS/CTS hw flow control	*/
+#define CONFIG_CMD_IO		/* Command to access IO ports	*/
 #define CONFIG_CMD_I2C		/* I2C serial bus support	*/
 #define CONFIG_CMD_IDE		/* IDE harddisk support		*/
 #define CONFIG_CMD_IMI		/* iminfo			*/
 #define CONFIG_CMD_IMLS		/* List all found images	*/
 #define CONFIG_CMD_IMMAP	/* IMMR dump support		*/
+#define CONFIG_CMD_IO		/* Access to X86 IO space	*/
 #define CONFIG_CMD_IRQ		/* irqinfo			*/
 #define CONFIG_CMD_ITEST	/* Integer (and string) test	*/
 #define CONFIG_CMD_JFFS2	/* JFFS2 Support		*/