2015-08-28 10:33:58

by Lee Jones

[permalink] [raw]
Subject: [PATCH v2 0/4] remoteproc: Add driver for STMicroelectronics platforms

ST's platforms often have multiple co-processors (usually ST40s or ST231s)
on-board. This provides the Linux-side infrastructure to flash and boot
them successfully.

This set has been tested on an STiH410-B2120.

v1 = v2:
- Remove Linux implementation specific comment from binding document
- Force debugfs '0' to shutdown co-processor - rather than !1
- Supply more detailed commit message
- Propagate errors back from .stop()
- Review GPL wording
- Supply original author's SoBs

Lee Jones (4):
ARM: STiH407: Add nodes for RemoteProc
remoteproc: dt: Provide bindings for ST's Remote Processor Controller
driver
remoteproc: Supply controller driver for ST's Remote Processors
remoteproc: debugfs: Add ability to boot remote processor using
debugfs

.../devicetree/bindings/remoteproc/st-rproc.txt | 35 +++
arch/arm/boot/dts/stih407-family.dtsi | 48 ++++
drivers/remoteproc/Kconfig | 9 +
drivers/remoteproc/Makefile | 1 +
drivers/remoteproc/remoteproc_debugfs.c | 29 ++
drivers/remoteproc/st_remoteproc.c | 301 +++++++++++++++++++++
6 files changed, 423 insertions(+)
create mode 100644 Documentation/devicetree/bindings/remoteproc/st-rproc.txt
create mode 100644 drivers/remoteproc/st_remoteproc.c

--
1.9.1


2015-08-28 10:34:53

by Lee Jones

[permalink] [raw]
Subject: [PATCH v2 1/4] ARM: STiH407: Add nodes for RemoteProc

Signed-off-by: Ludovic Barre <[email protected]>
Signed-off-by: Lee Jones <[email protected]>
---
arch/arm/boot/dts/stih407-family.dtsi | 48 +++++++++++++++++++++++++++++++++++
1 file changed, 48 insertions(+)

diff --git a/arch/arm/boot/dts/stih407-family.dtsi b/arch/arm/boot/dts/stih407-family.dtsi
index 33daa49..89a363c 100644
--- a/arch/arm/boot/dts/stih407-family.dtsi
+++ b/arch/arm/boot/dts/stih407-family.dtsi
@@ -608,5 +608,53 @@
status = "okay";
tx-only;
};
+
+ st231_gp0: st231-gp0@0 {
+ compatible = "st,st231-rproc";
+ reg = <0x40000000 0x01000000>;
+ reg-names = "carveout";
+ resets = <&softreset STIH407_ST231_GP0_SOFTRESET>;
+ reset-names = "sw_reset";
+ clocks = <&clk_s_c0_flexgen CLK_ST231_GP_0>;
+ clock-names = "rproc_clk";
+ clock-frequency = <600000000>;
+ st,syscfg-boot = <&syscfg_core 0x22C>;
+ };
+
+ st231_gp1: st231-gp1@0 {
+ compatible = "st,st231-rproc";
+ reg = <0x41000000 0x01000000>;
+ reg-names = "carveout";
+ resets = <&softreset STIH407_ST231_GP1_SOFTRESET>;
+ reset-names = "sw_reset";
+ clocks = <&clk_s_c0_flexgen CLK_ST231_GP_1>;
+ clock-names = "rproc_clk";
+ clock-frequency = <600000000>;
+ st,syscfg-boot = <&syscfg_core 0x220>;
+ };
+
+ st231_audio: st231-audio@0 {
+ compatible = "st,st231-rproc";
+ reg = <0x42000000 0x01000000>;
+ reg-names = "carveout";
+ resets = <&softreset STIH407_ST231_AUD_SOFTRESET>;
+ reset-names = "sw_reset";
+ clocks = <&clk_s_c0_flexgen CLK_ST231_AUD_0>;
+ clock-names = "rproc_clk";
+ clock-frequency = <600000000>;
+ st,syscfg-boot = <&syscfg_core 0x228>;
+ };
+
+ st231_dmu: st231-dmu@0 {
+ compatible = "st,st231-rproc";
+ reg = <0x43000000 0x01000000>;
+ reg-names = "carveout";
+ resets = <&softreset STIH407_ST231_DMU_SOFTRESET>;
+ reset-names = "sw_reset";
+ clocks = <&clk_s_c0_flexgen CLK_ST231_DMU>;
+ clock-names = "rproc_clk";
+ clock-frequency = <600000000>;
+ st,syscfg-boot = <&syscfg_core 0x224>;
+ };
};
};
--
1.9.1

2015-08-28 10:34:01

by Lee Jones

[permalink] [raw]
Subject: [PATCH v2 2/4] remoteproc: dt: Provide bindings for ST's Remote Processor Controller driver

Signed-off-by: Ludovic Barre <[email protected]>
Signed-off-by: Lee Jones <[email protected]>
---
.../devicetree/bindings/remoteproc/st-rproc.txt | 35 ++++++++++++++++++++++
1 file changed, 35 insertions(+)
create mode 100644 Documentation/devicetree/bindings/remoteproc/st-rproc.txt

diff --git a/Documentation/devicetree/bindings/remoteproc/st-rproc.txt b/Documentation/devicetree/bindings/remoteproc/st-rproc.txt
new file mode 100644
index 0000000..fbd7d78
--- /dev/null
+++ b/Documentation/devicetree/bindings/remoteproc/st-rproc.txt
@@ -0,0 +1,35 @@
+STMicroelectronics Remote Processor
+-----------------------------------
+
+This binding provides support for adjunct processors found on ST SoCs.
+
+The remote processors can be controlled from the bootloader or the primary OS.
+If the bootloader starts a remote processor processor the primary OS must detect
+its state and act accordingly.
+
+Required properties:
+- compatible Should be one of:
+ "st,st231-rproc"
+ "st,st40-rproc"
+- reg Size and length of reserved co-processor memory
+- resets Reset lines (See: ../reset/reset.txt)
+- reset-names Must be "sw_reset" and "pwr_reset"
+- clocks Clock for co-processor (See: ../clock/clock-bindings.txt)
+- clock-names Must be "rproc_clk"
+- clock-frequency Clock frequency to set co-processor at if the bootloader
+ hasn't already done so
+- st,syscfg-boot The register that holds the boot vector for the co-processor
+
+Example:
+
+ st231-audio@bae00000 {
+ compatible = "st,st231-rproc";
+ reg = <0xbae00000 0x01000000>;
+ reg-names = "rproc_mem";
+ resets = <&softreset STIH407_ST231_AUD_SOFTRESET>;
+ reset-names = "sw_reset";
+ clocks = <&clk_s_c0_flexgen CLK_ST231_AUD_0>;
+ clock-names = "rproc_clk";
+ clock-frequency = <600000000>;
+ st,syscfg-boot = <&syscfg_core 0x228>;
+ };
--
1.9.1

2015-08-28 10:34:38

by Lee Jones

[permalink] [raw]
Subject: [PATCH v2 3/4] remoteproc: Supply controller driver for ST's Remote Processors

Signed-off-by: Ludovic Barre <[email protected]>
Signed-off-by: Lee Jones <[email protected]>
---
drivers/remoteproc/Kconfig | 9 ++
drivers/remoteproc/Makefile | 1 +
drivers/remoteproc/st_remoteproc.c | 301 +++++++++++++++++++++++++++++++++++++
3 files changed, 311 insertions(+)
create mode 100644 drivers/remoteproc/st_remoteproc.c

diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig
index 28c711f..72e97d7 100644
--- a/drivers/remoteproc/Kconfig
+++ b/drivers/remoteproc/Kconfig
@@ -77,4 +77,13 @@ config DA8XX_REMOTEPROC
It's safe to say n here if you're not interested in multimedia
offloading.

+config ST_REMOTEPROC
+ tristate "ST remoteproc support"
+ depends on ARCH_STI
+ select REMOTEPROC
+ help
+ Say y here to support ST's adjunct processors via the remote
+ processor framework.
+ This can be either built-in or a loadable module.
+
endmenu
diff --git a/drivers/remoteproc/Makefile b/drivers/remoteproc/Makefile
index 81b04d1..279cb2e 100644
--- a/drivers/remoteproc/Makefile
+++ b/drivers/remoteproc/Makefile
@@ -11,3 +11,4 @@ obj-$(CONFIG_OMAP_REMOTEPROC) += omap_remoteproc.o
obj-$(CONFIG_STE_MODEM_RPROC) += ste_modem_rproc.o
obj-$(CONFIG_WKUP_M3_RPROC) += wkup_m3_rproc.o
obj-$(CONFIG_DA8XX_REMOTEPROC) += da8xx_remoteproc.o
+obj-$(CONFIG_ST_REMOTEPROC) += st_remoteproc.o
diff --git a/drivers/remoteproc/st_remoteproc.c b/drivers/remoteproc/st_remoteproc.c
new file mode 100644
index 0000000..96b784d
--- /dev/null
+++ b/drivers/remoteproc/st_remoteproc.c
@@ -0,0 +1,301 @@
+/*
+ * ST's Remote Processor Control Driver
+ *
+ * Copyright (C) 2015 STMicroelectronics - All Rights Reserved
+ *
+ * Author: Ludovic Barre <[email protected]>
+ *
+ * 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, or (at your option)
+ * any later version.
+ */
+
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/remoteproc.h>
+#include <linux/reset.h>
+
+struct st_rproc_config {
+ bool sw_reset;
+ bool pwr_reset;
+ u32 bootaddr_mask;
+};
+
+struct st_rproc {
+ struct st_rproc_config *config;
+ struct reset_control *sw_reset;
+ struct reset_control *pwr_reset;
+ struct clk *clk;
+ u32 clk_rate;
+ struct regmap *boot_base;
+ u32 boot_offset;
+};
+
+static int st_rproc_stop(struct rproc *rproc)
+{
+ struct st_rproc *st_rproc = rproc->priv;
+ int ret, err = 0;
+
+ if (st_rproc->config->sw_reset) {
+ ret = reset_control_assert(st_rproc->sw_reset);
+ if (ret)
+ dev_err(&rproc->dev, "Failed to assert S/W Reset\n");
+ }
+
+ if (st_rproc->config->pwr_reset) {
+ err = reset_control_assert(st_rproc->pwr_reset);
+ if (err)
+ dev_err(&rproc->dev, "Failed to assert Power Reset\n");
+ }
+
+ clk_disable(st_rproc->clk);
+
+ return ret ?: err;
+}
+
+static int st_rproc_start(struct rproc *rproc)
+{
+ struct st_rproc *st_rproc = rproc->priv;
+ int err;
+
+ regmap_update_bits(st_rproc->boot_base, st_rproc->boot_offset,
+ st_rproc->config->bootaddr_mask, rproc->bootaddr);
+
+ err = clk_enable(st_rproc->clk);
+ if (err) {
+ dev_err(&rproc->dev, "Failed to enable clock\n");
+ return err;
+ }
+
+ if (st_rproc->config->sw_reset) {
+ err = reset_control_deassert(st_rproc->sw_reset);
+ if (err) {
+ dev_err(&rproc->dev, "Failed to deassert S/W Reset\n");
+ return err;
+ }
+ }
+
+ if (st_rproc->config->pwr_reset) {
+ err = reset_control_deassert(st_rproc->pwr_reset);
+ if (err) {
+ dev_err(&rproc->dev, "Failed to deassert Power Reset\n");
+ return err;
+ }
+ }
+
+ dev_info(&rproc->dev, "Started from 0x%x\n", rproc->bootaddr);
+
+ return 0;
+}
+
+static struct rproc_ops st_rproc_ops = {
+ .start = st_rproc_start,
+ .stop = st_rproc_stop,
+};
+
+/*
+ * Fetch state of the processor: 0 is off, 1 is on.
+ */
+static int st_rproc_state(struct st_rproc *st_rproc)
+{
+ int reset_sw, reset_pwr;
+
+ reset_sw = st_rproc->config->sw_reset ?
+ reset_control_status(st_rproc->sw_reset) : 0;
+
+ reset_pwr = st_rproc->config->pwr_reset ?
+ reset_control_status(st_rproc->pwr_reset) : 0;
+
+ if (reset_sw < 0 || reset_pwr < 0)
+ return -EINVAL;
+
+ return !reset_sw && !reset_pwr;
+}
+
+static const struct st_rproc_config st40_rproc_cfg = {
+ .sw_reset = true,
+ .pwr_reset = true,
+ .bootaddr_mask = GENMASK(28, 1),
+};
+
+static const struct st_rproc_config st231_rproc_cfg = {
+ .sw_reset = true,
+ .pwr_reset = false,
+ .bootaddr_mask = GENMASK(31, 6),
+};
+
+static struct of_device_id st_rproc_match[] = {
+ { .compatible = "st,st40-rproc", .data = &st40_rproc_cfg },
+ { .compatible = "st,st231-rproc", .data = &st231_rproc_cfg },
+ {},
+};
+MODULE_DEVICE_TABLE(of, st_rproc_match);
+
+static int st_rproc_parse_dt(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct rproc *rproc = platform_get_drvdata(pdev);
+ struct st_rproc *st_rproc = rproc->priv;
+ struct device_node *np = dev->of_node;
+ struct resource *mem;
+ int err;
+
+ if (st_rproc->config->sw_reset) {
+ st_rproc->sw_reset = devm_reset_control_get(dev, "sw_reset");
+ if (IS_ERR(st_rproc->sw_reset)) {
+ dev_err(dev, "Failed to get S/W Reset\n");
+ return PTR_ERR(st_rproc->sw_reset);
+ }
+ }
+
+ if (st_rproc->config->pwr_reset) {
+ st_rproc->pwr_reset = devm_reset_control_get(dev, "pwr_reset");
+ if (IS_ERR(st_rproc->pwr_reset)) {
+ dev_err(dev, "Failed to get Power Reset\n");
+ return PTR_ERR(st_rproc->pwr_reset);
+ }
+ }
+
+ st_rproc->clk = devm_clk_get(dev, "rproc_clk");
+ if (IS_ERR(st_rproc->clk)) {
+ dev_err(dev, "Failed to get clock\n");
+ return PTR_ERR(st_rproc->clk);
+ }
+
+ err = of_property_read_u32(np, "clock-frequency", &st_rproc->clk_rate);
+ if (err) {
+ dev_err(dev, "failed to get clock frequency\n");
+ return err;
+ }
+
+
+ st_rproc->boot_base =
+ syscon_regmap_lookup_by_phandle(np, "st,syscfg-boot");
+ if (!st_rproc->boot_base) {
+ dev_err(dev, "Boot base not found\n");
+ return -EINVAL;
+ }
+
+ err = of_property_read_u32_index(np, "st,syscfg-boot", 1,
+ &st_rproc->boot_offset);
+ if (err) {
+ dev_err(dev, "Boot offset not found\n");
+ return -EINVAL;
+ }
+
+ mem = platform_get_resource_byname(pdev, IORESOURCE_MEM, "carveout");
+ if (!mem) {
+ dev_err(dev, "no rproc memory definition\n");
+ return -ENXIO;
+ }
+
+ if (!devm_request_mem_region(dev, mem->start,
+ resource_size(mem), pdev->name)) {
+ dev_err(dev, "failed to get memory region resource\n");
+ return -EBUSY;
+ }
+ err = dmam_declare_coherent_memory(dev, mem->start, mem->start,
+ resource_size(mem),
+ DMA_MEMORY_MAP |
+ DMA_MEMORY_EXCLUSIVE);
+ if (err < 0) {
+ dev_err(dev, "cannot declare coherent memory: %d\n", err);
+ return -ENXIO;
+ }
+
+ err = clk_prepare(st_rproc->clk);
+ if (err)
+ dev_err(dev, "failed to get clock\n");
+
+ return err;
+}
+
+static int st_rproc_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ const struct of_device_id *match;
+ struct st_rproc *st_rproc;
+ struct device_node *np = dev->of_node;
+ struct rproc *rproc;
+ int enabled;
+ int ret;
+
+ match = of_match_device((st_rproc_match), dev);
+ if (!match || !match->data) {
+ dev_err(dev, "No device match found\n");
+ return -ENODEV;
+ }
+
+ rproc = rproc_alloc(dev, np->name, &st_rproc_ops,
+ NULL, sizeof(*st_rproc));
+ if (!rproc)
+ return -ENOMEM;
+
+ st_rproc = rproc->priv;
+ st_rproc->config = (struct st_rproc_config *)match->data;
+ platform_set_drvdata(pdev, rproc);
+
+ ret = st_rproc_parse_dt(pdev);
+ if (ret)
+ goto free_rproc;
+
+ ret = st_rproc_state(st_rproc);
+ if (ret < 0)
+ goto free_rproc;
+ enabled = ret;
+
+ if (enabled) {
+ atomic_inc(&rproc->power);
+ rproc->state = RPROC_RUNNING;
+ } else {
+ clk_set_rate(st_rproc->clk, st_rproc->clk_rate);
+ }
+
+ ret = rproc_add(rproc);
+ if (ret)
+ goto free_rproc;
+
+ return 0;
+
+free_rproc:
+ rproc_put(rproc);
+ return ret;
+}
+
+static int st_rproc_remove(struct platform_device *pdev)
+{
+ struct rproc *rproc = platform_get_drvdata(pdev);
+ struct st_rproc *st_rproc = rproc->priv;
+
+ rproc_del(rproc);
+
+ clk_disable_unprepare(st_rproc->clk);
+
+ rproc_put(rproc);
+
+ return 0;
+}
+
+static struct platform_driver st_rproc_driver = {
+ .probe = st_rproc_probe,
+ .remove = st_rproc_remove,
+ .driver = {
+ .name = "st-rproc",
+ .of_match_table = of_match_ptr(st_rproc_match),
+ },
+};
+module_platform_driver(st_rproc_driver);
+
+MODULE_DESCRIPTION("ST Remote Processor Control Driver");
+MODULE_AUTHOR("Ludovic.barre <[email protected]>");
+MODULE_LICENSE("GPL v2");
--
1.9.1

2015-08-28 10:34:11

by Lee Jones

[permalink] [raw]
Subject: [PATCH v2 4/4] remoteproc: debugfs: Add ability to boot remote processor using debugfs

This functionality is especially useful during the testing phase. When
used in conjunction with Mailbox's Test Framework we can trivially conduct
end-to-end testing i.e. boot co-processor, send and receive messages to
the co-processor, then shut it down again (repeat as required).

Signed-off-by: Ludovic Barre <[email protected]>
Signed-off-by: Lee Jones <[email protected]>
---
drivers/remoteproc/remoteproc_debugfs.c | 29 +++++++++++++++++++++++++++++
1 file changed, 29 insertions(+)

diff --git a/drivers/remoteproc/remoteproc_debugfs.c b/drivers/remoteproc/remoteproc_debugfs.c
index 9d30809..464470d 100644
--- a/drivers/remoteproc/remoteproc_debugfs.c
+++ b/drivers/remoteproc/remoteproc_debugfs.c
@@ -88,8 +88,37 @@ static ssize_t rproc_state_read(struct file *filp, char __user *userbuf,
return simple_read_from_buffer(userbuf, count, ppos, buf, i);
}

+static ssize_t rproc_state_write(struct file *filp, const char __user *userbuf,
+ size_t count, loff_t *ppos)
+{
+ struct rproc *rproc = filp->private_data;
+ char buf[2];
+ int ret;
+
+ ret = copy_from_user(buf, userbuf, 1);
+ if (ret)
+ return -EFAULT;
+
+ switch (buf[0]) {
+ case '0':
+ rproc_shutdown(rproc);
+ break;
+ case '1':
+ ret = rproc_boot(rproc);
+ if (ret)
+ dev_warn(&rproc->dev, "Boot failed: %d\n", ret);
+ break;
+ default:
+ dev_err(&rproc->dev, "Unrecognised option: %x\n", buf[1]);
+ return -EINVAL;
+ }
+
+ return count;
+}
+
static const struct file_operations rproc_state_ops = {
.read = rproc_state_read,
+ .write = rproc_state_write,
.open = simple_open,
.llseek = generic_file_llseek,
};
--
1.9.1

2015-08-28 15:24:43

by Lynch, Nathan

[permalink] [raw]
Subject: Re: [PATCH v2 4/4] remoteproc: debugfs: Add ability to boot remote processor using debugfs

On 08/28/2015 05:31 AM, Lee Jones wrote:
> +static ssize_t rproc_state_write(struct file *filp, const char __user *userbuf,
> + size_t count, loff_t *ppos)
> +{
> + struct rproc *rproc = filp->private_data;
> + char buf[2];
> + int ret;
> +
> + ret = copy_from_user(buf, userbuf, 1);
> + if (ret)
> + return -EFAULT;
> +
> + switch (buf[0]) {
> + case '0':
> + rproc_shutdown(rproc);
> + break;
> + case '1':
> + ret = rproc_boot(rproc);
> + if (ret)
> + dev_warn(&rproc->dev, "Boot failed: %d\n", ret);
> + break;
> + default:
> + dev_err(&rproc->dev, "Unrecognised option: %x\n", buf[1]);
> + return -EINVAL;

This prints uninitialized kernel stack contents instead of what was
copied from user space.

Is the dev_err statement really necessary anyway?


> + }
> +
> + return count;
> +}

If rproc_boot fails, that should be reflected in the syscall result.

This interface is essentially exposing the remoteproc->power refcount to
user space; is that okay? Seems like it makes it easy to underflow
remoteproc->power through successive shutdown calls.

The other debugfs interface in remoteproc that has a write method
(recovery) accepts more expressive string commands as opposed to 0/1.
It would be more consistent for this interface to take commands such as
"boot" and "shutdown" IMO.

2015-08-28 16:25:48

by Lynch, Nathan

[permalink] [raw]
Subject: Re: [PATCH v2 3/4] remoteproc: Supply controller driver for ST's Remote Processors

On 08/28/2015 05:31 AM, Lee Jones wrote:
> diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig
> index 28c711f..72e97d7 100644
> --- a/drivers/remoteproc/Kconfig
> +++ b/drivers/remoteproc/Kconfig
> @@ -77,4 +77,13 @@ config DA8XX_REMOTEPROC
> It's safe to say n here if you're not interested in multimedia
> offloading.
>
> +config ST_REMOTEPROC
> + tristate "ST remoteproc support"
> + depends on ARCH_STI
> + select REMOTEPROC
> + help
> + Say y here to support ST's adjunct processors via the remote
> + processor framework.
> + This can be either built-in or a loadable module.
> +

The code uses reset_control_* APIs, so this should depend on
RESET_CONTROLLER, no?

> +/*
> + * ST's Remote Processor Control Driver
> + *
> + * Copyright (C) 2015 STMicroelectronics - All Rights Reserved
> + *
> + * Author: Ludovic Barre <[email protected]>
> + *
> + * 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, or (at your option)
> + * any later version.
> + */

OK, but:

> +MODULE_LICENSE("GPL v2");

These are not in agreement. You want "GPL" for MODULE_LICENSE if you
intend v2 or later.


> +static int st_rproc_stop(struct rproc *rproc)
> +{
> + struct st_rproc *st_rproc = rproc->priv;
> + int ret, err = 0;
> +
> + if (st_rproc->config->sw_reset) {
> + ret = reset_control_assert(st_rproc->sw_reset);
> + if (ret)
> + dev_err(&rproc->dev, "Failed to assert S/W Reset\n");
> + }
> +
> + if (st_rproc->config->pwr_reset) {
> + err = reset_control_assert(st_rproc->pwr_reset);
> + if (err)
> + dev_err(&rproc->dev, "Failed to assert Power Reset\n");
> + }
> +
> + clk_disable(st_rproc->clk);
> +
> + return ret ?: err;
> +}

Sorry, but I think this is a stylistically inadequate response to my
earlier comments. At least name the status variables sw_ret and pwr_ret
or something. And it looks like ret could be used uninitialized.

Also, do you want to unconditionally call clk_disable even if you've
encountered errors?


> +static int st_rproc_start(struct rproc *rproc)
> +{
> + struct st_rproc *st_rproc = rproc->priv;
> + int err;
> +
> + regmap_update_bits(st_rproc->boot_base, st_rproc->boot_offset,
> + st_rproc->config->bootaddr_mask, rproc->bootaddr);
> +
> + err = clk_enable(st_rproc->clk);
> + if (err) {
> + dev_err(&rproc->dev, "Failed to enable clock\n");
> + return err;
> + }
> +
> + if (st_rproc->config->sw_reset) {
> + err = reset_control_deassert(st_rproc->sw_reset);
> + if (err) {
> + dev_err(&rproc->dev, "Failed to deassert S/W Reset\n");
> + return err;
> + }
> + }
> +
> + if (st_rproc->config->pwr_reset) {
> + err = reset_control_deassert(st_rproc->pwr_reset);
> + if (err) {
> + dev_err(&rproc->dev, "Failed to deassert Power Reset\n");
> + return err;
> + }
> + }
> +
> + dev_info(&rproc->dev, "Started from 0x%x\n", rproc->bootaddr);
> +
> + return 0;
> +}

Does this want to unwind any of its operations if it encounters a failure?

2015-08-28 17:20:03

by Florian Fainelli

[permalink] [raw]
Subject: Re: [PATCH v2 4/4] remoteproc: debugfs: Add ability to boot remote processor using debugfs

On 28/08/15 03:31, Lee Jones wrote:
> This functionality is especially useful during the testing phase. When
> used in conjunction with Mailbox's Test Framework we can trivially conduct
> end-to-end testing i.e. boot co-processor, send and receive messages to
> the co-processor, then shut it down again (repeat as required).

This does not strike me as a particularly well defined nor suitable
interface for controlling a remote processor's state. I know you are
just extending the existing debugfs interface here, but someone ought to
remove that piece of code and make it a proper character device or
netlink or whatever that allows someone to get proper signaling of
what's going on with the remote processor state by polling or listening
to a socket.

What's the intended use case behind debugfs for this after all? Is your
application expected to keep reading the state file in a loop until it
is happy and reads "running", how is that not racy by nature?

>
> Signed-off-by: Ludovic Barre <[email protected]>
> Signed-off-by: Lee Jones <[email protected]>
> ---
> drivers/remoteproc/remoteproc_debugfs.c | 29 +++++++++++++++++++++++++++++
> 1 file changed, 29 insertions(+)
>
> diff --git a/drivers/remoteproc/remoteproc_debugfs.c b/drivers/remoteproc/remoteproc_debugfs.c
> index 9d30809..464470d 100644
> --- a/drivers/remoteproc/remoteproc_debugfs.c
> +++ b/drivers/remoteproc/remoteproc_debugfs.c
> @@ -88,8 +88,37 @@ static ssize_t rproc_state_read(struct file *filp, char __user *userbuf,
> return simple_read_from_buffer(userbuf, count, ppos, buf, i);
> }
>
> +static ssize_t rproc_state_write(struct file *filp, const char __user *userbuf,
> + size_t count, loff_t *ppos)
> +{
> + struct rproc *rproc = filp->private_data;
> + char buf[2];
> + int ret;
> +
> + ret = copy_from_user(buf, userbuf, 1);
> + if (ret)
> + return -EFAULT;
> +
> + switch (buf[0]) {
> + case '0':
> + rproc_shutdown(rproc);
> + break;
> + case '1':
> + ret = rproc_boot(rproc);
> + if (ret)
> + dev_warn(&rproc->dev, "Boot failed: %d\n", ret);
> + break;
> + default:
> + dev_err(&rproc->dev, "Unrecognised option: %x\n", buf[1]);
> + return -EINVAL;
> + }
> +
> + return count;
> +}
> +
> static const struct file_operations rproc_state_ops = {
> .read = rproc_state_read,
> + .write = rproc_state_write,
> .open = simple_open,
> .llseek = generic_file_llseek,
> };
>


--
Florian

2015-08-31 15:28:26

by Rob Herring

[permalink] [raw]
Subject: Re: [PATCH v2 2/4] remoteproc: dt: Provide bindings for ST's Remote Processor Controller driver

On Fri, Aug 28, 2015 at 5:31 AM, Lee Jones <[email protected]> wrote:
> Signed-off-by: Ludovic Barre <[email protected]>
> Signed-off-by: Lee Jones <[email protected]>
> ---
> .../devicetree/bindings/remoteproc/st-rproc.txt | 35 ++++++++++++++++++++++
> 1 file changed, 35 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/remoteproc/st-rproc.txt
>
> diff --git a/Documentation/devicetree/bindings/remoteproc/st-rproc.txt b/Documentation/devicetree/bindings/remoteproc/st-rproc.txt
> new file mode 100644
> index 0000000..fbd7d78
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/remoteproc/st-rproc.txt
> @@ -0,0 +1,35 @@
> +STMicroelectronics Remote Processor

"remote processor" is what STM datasheets call them? This seems like
Linux naming is leaking in here.

Rob