[U-Boot] [PATCH v3 0/2] x86: SCU and PMU drivers for Intel MID

[U-Boot] [PATCH v3 0/2] x86: SCU and PMU drivers for Intel MID

[Andy Shevchenko]

There are two crucial drivers to make Intel MID platforms functional in
U-Boot:
	SCU which stands for System Controller Unit
	PMU which stands for Power Management Unit

Since v2:
- resend with cover letter including changes from previous versions

Since v1:

Common:
- convert to use REGMAP instead of constant addressed IO
- rewrite as UCLASS_SYSCON modules
- move to arch/x86/lib since it's related to x86 only and there are
  already another UCLASS_SYSCON modules there

SCU:
- convert function documentation to have header and body and be
  consistent
- shrink header and remove unneeded attributes
- drop busy loop counter from 3m to 100k as per driver in Linux kernel

PMU:
- convert to be more generic and move Tangier related part to its own
  folder (the latter out of scope of this series)

Andy Shevchenko (1):
  x86: Introduce minimal PMU driver for Intel MID platforms

Felipe Balbi (1):
  x86: Add SCU IPC driver for Intel MID platforms

 arch/x86/Kconfig           |   2 +
 arch/x86/include/asm/cpu.h |   2 +
 arch/x86/include/asm/pmu.h |  11 +++
 arch/x86/include/asm/scu.h |  28 ++++++++
 arch/x86/lib/Makefile      |   2 +
 arch/x86/lib/pmu.c         | 117 +++++++++++++++++++++++++++++++
 arch/x86/lib/scu.c         | 168 +++++++++++++++++++++++++++++++++++++++++++++
 7 files changed, 330 insertions(+)
 create mode 100644 arch/x86/include/asm/pmu.h
 create mode 100644 arch/x86/include/asm/scu.h
 create mode 100644 arch/x86/lib/pmu.c
 create mode 100644 arch/x86/lib/scu.c

-- 
2.11.0

[U-Boot] [PATCH v3 1/2] x86: Add SCU IPC driver for Intel MID platforms

[Andy Shevchenko]

From: Felipe Balbi <felipe.balbi@linux.intel.com>

Intel MID platforms have few microcontrollers inside SoC, one of them
is so called System Controller Unit (SCU).

Here is the driver to communicate with microcontroller.

Signed-off-by: Vincent Tinelli <vincent.tinelli@intel.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 arch/x86/Kconfig           |   2 +
 arch/x86/include/asm/cpu.h |   1 +
 arch/x86/include/asm/scu.h |  28 ++++++++
 arch/x86/lib/Makefile      |   1 +
 arch/x86/lib/scu.c         | 168 +++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 200 insertions(+)
 create mode 100644 arch/x86/include/asm/scu.h
 create mode 100644 arch/x86/lib/scu.c

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index dfdd7564ea..9a1ecd7907 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -83,6 +83,8 @@ endchoice
 # subarchitectures-specific options below
 config INTEL_MID
 	bool "Intel MID platform support"
+	select REGMAP
+	select SYSCON
 	help
 	  Select to build a U-Boot capable of supporting Intel MID
 	  (Mobile Internet Device) platform systems which do not have
diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h
index c651f2f594..0ee13b1eb1 100644
--- a/arch/x86/include/asm/cpu.h
+++ b/arch/x86/include/asm/cpu.h
@@ -54,6 +54,7 @@ enum {
 	X86_NONE,
 	X86_SYSCON_ME,		/* Intel Management Engine */
 	X86_SYSCON_PINCONF,	/* Intel x86 pin configuration */
+	X86_SYSCON_SCU,		/* System Controller Unit */
 };
 
 struct cpuid_result {
diff --git a/arch/x86/include/asm/scu.h b/arch/x86/include/asm/scu.h
new file mode 100644
index 0000000000..876363cb5c
--- /dev/null
+++ b/arch/x86/include/asm/scu.h
@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2017 Intel Corporation
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+#ifndef _X86_ASM_SCU_IPC_H_
+#define _X86_ASM_SCU_IPC_H_
+
+/* IPC defines the following message types */
+#define IPCMSG_WARM_RESET		0xF0
+#define IPCMSG_COLD_RESET		0xF1
+#define IPCMSG_SOFT_RESET		0xF2
+#define IPCMSG_COLD_BOOT		0xF3
+#define IPCMSG_GET_FW_REVISION		0xF4
+#define IPCMSG_WATCHDOG_TIMER		0xF8	/* Set Kernel Watchdog Threshold */
+
+struct ipc_ifwi_version {
+	u16	minor;
+	u8	major;
+	u8	hardware_id;
+	u32	reserved[3];
+};
+
+/* Issue commands to the SCU with or without data */
+int scu_ipc_simple_command(u32 cmd, u32 sub);
+int scu_ipc_command(u32 cmd, u32 sub, u32 *in, int inlen, u32 *out, int outlen);
+
+#endif	/* _X86_ASM_SCU_IPC_H_ */
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index 1c2c085179..320e45e4a0 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -32,6 +32,7 @@ obj-y	+= pirq_routing.o
 obj-y	+= relocate.o
 obj-y += physmem.o
 obj-$(CONFIG_X86_RAMTEST) += ramtest.o
+obj-$(CONFIG_INTEL_MID) += scu.o
 obj-y	+= sections.o
 obj-y += sfi.o
 obj-y	+= string.o
diff --git a/arch/x86/lib/scu.c b/arch/x86/lib/scu.c
new file mode 100644
index 0000000000..bb23d0b829
--- /dev/null
+++ b/arch/x86/lib/scu.c
@@ -0,0 +1,168 @@
+/*
+ * Copyright (c) 2017 Intel Corporation
+ *
+ * Intel Mobile Internet Devices (MID) based on Intel Atom SoCs have few
+ * microcontrollers inside to do some auxiliary tasks. One of such
+ * microcontroller is System Controller Unit (SCU) which, in particular,
+ * is servicing watchdog and controlling system reset function.
+ *
+ * This driver enables IPC channel to SCU.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+#include <common.h>
+#include <dm.h>
+#include <regmap.h>
+#include <syscon.h>
+#include <asm/cpu.h>
+#include <asm/scu.h>
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+
+/* SCU register map */
+struct ipc_regs {
+	u32 cmd;
+	u32 status;
+	u32 sptr;
+	u32 dptr;
+	u32 reserved[28];
+	u32 wbuf[4];
+	u32 rbuf[4];
+};
+
+struct scu {
+	struct ipc_regs *regs;
+};
+
+/**
+ * scu_ipc_send_command() - send command to SCU
+ * @regs: register map of SCU
+ * @cmd: command
+ *
+ * Command Register (Write Only):
+ * A write to this register results in an interrupt to the SCU core processor
+ * Format:
+ * |rfu2(8) | size(8) | command id(4) | rfu1(3) | ioc(1) | command(8)|
+ */
+static void scu_ipc_send_command(struct ipc_regs *regs, u32 cmd)
+{
+	writel(cmd, &regs->cmd);
+}
+
+/**
+ * scu_ipc_check_status() - check status of last command
+ * @regs: register map of SCU
+ *
+ * Status Register (Read Only):
+ * Driver will read this register to get the ready/busy status of the IPC
+ * block and error status of the IPC command that was just processed by SCU
+ * Format:
+ * |rfu3(8)|error code(8)|initiator id(8)|cmd id(4)|rfu1(2)|error(1)|busy(1)|
+ */
+static int scu_ipc_check_status(struct ipc_regs *regs)
+{
+	int loop_count = 100000;
+	int status;
+
+	do {
+		status = readl(&regs->status);
+		if (!(status & BIT(0)))
+			break;
+
+		udelay(1);
+	} while (--loop_count);
+	if (!loop_count)
+		return -ETIMEDOUT;
+
+	if (status & BIT(1)) {
+		printf("%s() status=0x%08x\n", __func__, status);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int scu_ipc_cmd(struct ipc_regs *regs, u32 cmd, u32 sub,
+		       u32 *in, int inlen, u32 *out, int outlen)
+{
+	int i, err;
+
+	for (i = 0; i < inlen; i++)
+		writel(*in++, &regs->wbuf[i]);
+
+	scu_ipc_send_command(regs, (inlen << 16) | (sub << 12) | cmd);
+	err = scu_ipc_check_status(regs);
+
+	if (!err) {
+		for (i = 0; i < outlen; i++)
+			*out++ = readl(&regs->rbuf[i]);
+	}
+
+	return err;
+}
+
+/**
+ * scu_ipc_simple_command() - send a simple command
+ * @cmd: command
+ * @sub: sub type
+ *
+ * Issue a simple command to the SCU. Do not use this interface if
+ * you must then access data as any data values may be overwritten
+ * by another SCU access by the time this function returns.
+ *
+ * This function may sleep. Locking for SCU accesses is handled for
+ * the caller.
+ */
+int scu_ipc_simple_command(u32 cmd, u32 sub)
+{
+	struct scu *scu;
+	struct udevice *dev;
+	int ret;
+
+	ret = syscon_get_by_driver_data(X86_SYSCON_SCU, &dev);
+	if (ret)
+		return ret;
+
+	scu = dev_get_priv(dev);
+
+	scu_ipc_send_command(scu->regs, sub << 12 | cmd);
+	return scu_ipc_check_status(scu->regs);
+}
+
+int scu_ipc_command(u32 cmd, u32 sub, u32 *in, int inlen, u32 *out, int outlen)
+{
+	struct scu *scu;
+	struct udevice *dev;
+	int ret;
+
+	ret = syscon_get_by_driver_data(X86_SYSCON_SCU, &dev);
+	if (ret)
+		return ret;
+
+	scu = dev_get_priv(dev);
+
+	return scu_ipc_cmd(scu->regs, cmd, sub, in, inlen, out, outlen);
+}
+
+static int scu_ipc_probe(struct udevice *dev)
+{
+	struct scu *scu = dev_get_priv(dev);
+
+	scu->regs = syscon_get_first_range(X86_SYSCON_SCU);
+
+	return 0;
+}
+
+static const struct udevice_id scu_ipc_match[] = {
+	{ .compatible = "intel,scu-ipc", .data = X86_SYSCON_SCU },
+	{ /* sentinel */ }
+};
+
+U_BOOT_DRIVER(scu_ipc) = {
+	.name		= "scu_ipc",
+	.id		= UCLASS_SYSCON,
+	.of_match	= scu_ipc_match,
+	.probe		= scu_ipc_probe,
+	.priv_auto_alloc_size = sizeof(struct scu),
+};
-- 
2.11.0

[U-Boot] [PATCH v3 2/2] x86: Introduce minimal PMU driver for Intel MID platforms

[Andy Shevchenko]

This simple PMU driver allows to tyrn power on and off for selected
devices. In particularly Intel Tangier needs to power on SDHCI
controllers in order to access to them during board initialization.

In the future it might be expanded to cover other Intel MID platforms,
that's why it's located under arch/x86/lib and called pmu.c.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 arch/x86/include/asm/cpu.h |   1 +
 arch/x86/include/asm/pmu.h |  11 +++++
 arch/x86/lib/Makefile      |   1 +
 arch/x86/lib/pmu.c         | 117 +++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 130 insertions(+)
 create mode 100644 arch/x86/include/asm/pmu.h
 create mode 100644 arch/x86/lib/pmu.c

diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h
index 0ee13b1eb1..c00687a20a 100644
--- a/arch/x86/include/asm/cpu.h
+++ b/arch/x86/include/asm/cpu.h
@@ -54,6 +54,7 @@ enum {
 	X86_NONE,
 	X86_SYSCON_ME,		/* Intel Management Engine */
 	X86_SYSCON_PINCONF,	/* Intel x86 pin configuration */
+	X86_SYSCON_PMU,		/* Power Management Unit */
 	X86_SYSCON_SCU,		/* System Controller Unit */
 };
 
diff --git a/arch/x86/include/asm/pmu.h b/arch/x86/include/asm/pmu.h
new file mode 100644
index 0000000000..96b968ff8f
--- /dev/null
+++ b/arch/x86/include/asm/pmu.h
@@ -0,0 +1,11 @@
+/*
+ * Copyright (c) 2017 Intel Corporation
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+#ifndef _X86_ASM_PMU_IPC_H_
+#define _X86_ASM_PMU_IPC_H_
+
+int pmu_turn_power(unsigned int lss, bool on);
+
+#endif	/* _X86_ASM_PMU_IPC_H_ */
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index 320e45e4a0..d1ad37af64 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -31,6 +31,7 @@ obj-y	+= pinctrl_ich6.o
 obj-y	+= pirq_routing.o
 obj-y	+= relocate.o
 obj-y += physmem.o
+obj-$(CONFIG_INTEL_MID) += pmu.o
 obj-$(CONFIG_X86_RAMTEST) += ramtest.o
 obj-$(CONFIG_INTEL_MID) += scu.o
 obj-y	+= sections.o
diff --git a/arch/x86/lib/pmu.c b/arch/x86/lib/pmu.c
new file mode 100644
index 0000000000..4ceab8dc64
--- /dev/null
+++ b/arch/x86/lib/pmu.c
@@ -0,0 +1,117 @@
+/*
+ * Copyright (c) 2017 Intel Corporation
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+#include <common.h>
+#include <dm.h>
+#include <regmap.h>
+#include <syscon.h>
+#include <asm/cpu.h>
+#include <asm/pmu.h>
+#include <linux/errno.h>
+#include <linux/io.h>
+
+/* Registers */
+struct pmu_regs {
+	u32	sts;
+	u32	cmd;
+	u32	ics;
+	u32	reserved;
+	u32	wkc[4];
+	u32	wks[4];
+	u32	ssc[4];
+	u32	sss[4];
+};
+
+/* Bits in PMU_REGS_STS */
+#define PMU_REGS_STS_BUSY		(1 << 8)
+
+struct pmu_mid {
+	struct pmu_regs *regs;
+};
+
+static int pmu_read_status(struct pmu_regs *regs)
+{
+	int retry = 500000;
+	u32 val;
+
+	do {
+		val = readl(&regs->sts);
+		if (!(val & PMU_REGS_STS_BUSY))
+			return 0;
+
+		udelay(1);
+	} while (--retry);
+
+	printf("WARNING: PMU still busy\n");
+	return -EBUSY;
+}
+
+static int pmu_power_lss(struct pmu_regs *regs, unsigned int lss, bool on)
+{
+	unsigned int offset = (lss * 2) / 32;
+	unsigned int shift = (lss * 2) % 32;
+	u32 ssc;
+	int ret;
+
+	/* Check PMU status */
+	ret = pmu_read_status(regs);
+	if (ret)
+		return ret;
+
+	/* Read PMU values */
+	ssc = readl(&regs->sss[offset]);
+
+	/* Modify PMU values */
+	if (on)
+		ssc &= ~(0x3 << shift);		/* D0 */
+	else
+		ssc |= 0x3 << shift;		/* D3hot */
+
+	/* Write modified PMU values */
+	writel(ssc, &regs->ssc[offset]);
+
+	/* Update modified PMU values */
+	writel(0x00002201, &regs->cmd);
+
+	/* Check PMU status */
+	return pmu_read_status(regs);
+}
+
+int pmu_turn_power(unsigned int lss, bool on)
+{
+	struct pmu_mid *pmu;
+	struct udevice *dev;
+	int ret;
+
+	ret = syscon_get_by_driver_data(X86_SYSCON_PMU, &dev);
+	if (ret)
+		return ret;
+
+	pmu = dev_get_priv(dev);
+
+	return pmu_power_lss(pmu->regs, lss, on);
+}
+
+static int pmu_mid_probe(struct udevice *dev)
+{
+	struct pmu_mid *pmu = dev_get_priv(dev);
+
+	pmu->regs = syscon_get_first_range(X86_SYSCON_PMU);
+
+	return 0;
+}
+
+static const struct udevice_id pmu_mid_match[] = {
+	{ .compatible = "intel,pmu-mid", .data = X86_SYSCON_PMU },
+	{ /* sentinel */ }
+};
+
+U_BOOT_DRIVER(intel_mid_pmu) = {
+	.name		= "pmu_mid",
+	.id		= UCLASS_SYSCON,
+	.of_match	= pmu_mid_match,
+	.probe		= pmu_mid_probe,
+	.priv_auto_alloc_size = sizeof(struct pmu_mid),
+};
-- 
2.11.0

[U-Boot] [PATCH v3 1/2] x86: Add SCU IPC driver for Intel MID platforms

[Simon Glass]

Hi Andy,

On 1 April 2017 at 07:21, Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
> From: Felipe Balbi <felipe.balbi@linux.intel.com>
>
> Intel MID platforms have few microcontrollers inside SoC, one of them
> is so called System Controller Unit (SCU).
>
> Here is the driver to communicate with microcontroller.
>
> Signed-off-by: Vincent Tinelli <vincent.tinelli@intel.com>
> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

Acked-by: Simon Glass <sjg@chromium.org>

If you can it is better to put the change log in each patch. Patman can help.

BTW if you end up resending, please use lower-case hex.

> ---
>  arch/x86/Kconfig           |   2 +
>  arch/x86/include/asm/cpu.h |   1 +
>  arch/x86/include/asm/scu.h |  28 ++++++++
>  arch/x86/lib/Makefile      |   1 +
>  arch/x86/lib/scu.c         | 168 +++++++++++++++++++++++++++++++++++++++++++++
>  5 files changed, 200 insertions(+)
>  create mode 100644 arch/x86/include/asm/scu.h
>  create mode 100644 arch/x86/lib/scu.c

Regards,
Simon

[U-Boot] [PATCH v3 2/2] x86: Introduce minimal PMU driver for Intel MID platforms

[Simon Glass]

Hi Andy,

On 1 April 2017 at 07:21, Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
> This simple PMU driver allows to tyrn power on and off for selected
> devices. In particularly Intel Tangier needs to power on SDHCI
> controllers in order to access to them during board initialization.
>
> In the future it might be expanded to cover other Intel MID platforms,
> that's why it's located under arch/x86/lib and called pmu.c.
>
> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
>  arch/x86/include/asm/cpu.h |   1 +
>  arch/x86/include/asm/pmu.h |  11 +++++
>  arch/x86/lib/Makefile      |   1 +
>  arch/x86/lib/pmu.c         | 117 +++++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 130 insertions(+)
>  create mode 100644 arch/x86/include/asm/pmu.h
>  create mode 100644 arch/x86/lib/pmu.c

Reviewed-by: Simon Glass <sjg@chromium.org>

Have you considered making this a PMIC driver? Then you could avoid
exporting the function. Also I see that we need to do that sometimes
with Intel platforms.

[U-Boot] [PATCH v3 1/2] x86: Add SCU IPC driver for Intel MID platforms

[Bin Meng]

On Thu, Apr 6, 2017 at 11:44 AM, Simon Glass <sjg@chromium.org> wrote:
> Hi Andy,
>
> On 1 April 2017 at 07:21, Andy Shevchenko
> <andriy.shevchenko@linux.intel.com> wrote:
>> From: Felipe Balbi <felipe.balbi@linux.intel.com>
>>
>> Intel MID platforms have few microcontrollers inside SoC, one of them
>> is so called System Controller Unit (SCU).
>>
>> Here is the driver to communicate with microcontroller.
>>
>> Signed-off-by: Vincent Tinelli <vincent.tinelli@intel.com>
>> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
>> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
>
> Acked-by: Simon Glass <sjg@chromium.org>
>
> If you can it is better to put the change log in each patch. Patman can help.
>
> BTW if you end up resending, please use lower-case hex.
>

Fixed the lower-case hex, and one checkpatch warning:

WARNING: line over 80 characters
#82: FILE: arch/x86/include/asm/scu.h:15:
+#define IPCMSG_WATCHDOG_TIMER          0xF8    /* Set Kernel Watchdog
Threshold */

and, applied to u-boot-x86, thanks!

[U-Boot] [PATCH v3 2/2] x86: Introduce minimal PMU driver for Intel MID platforms

[Bin Meng]

On Thu, Apr 6, 2017 at 11:44 AM, Simon Glass <sjg@chromium.org> wrote:
> Hi Andy,
>
> On 1 April 2017 at 07:21, Andy Shevchenko
> <andriy.shevchenko@linux.intel.com> wrote:
>> This simple PMU driver allows to tyrn power on and off for selected
>> devices. In particularly Intel Tangier needs to power on SDHCI
>> controllers in order to access to them during board initialization.
>>
>> In the future it might be expanded to cover other Intel MID platforms,
>> that's why it's located under arch/x86/lib and called pmu.c.
>>
>> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
>> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
>> ---
>>  arch/x86/include/asm/cpu.h |   1 +
>>  arch/x86/include/asm/pmu.h |  11 +++++
>>  arch/x86/lib/Makefile      |   1 +
>>  arch/x86/lib/pmu.c         | 117 +++++++++++++++++++++++++++++++++++++++++++++
>>  4 files changed, 130 insertions(+)
>>  create mode 100644 arch/x86/include/asm/pmu.h
>>  create mode 100644 arch/x86/lib/pmu.c
>
> Reviewed-by: Simon Glass <sjg@chromium.org>
>
> Have you considered making this a PMIC driver? Then you could avoid
> exporting the function. Also I see that we need to do that sometimes
> with Intel platforms.

applied to u-boot-x86, thanks!