Hi Etienne,
On Mon, 7 Sep 2020 at 08:50, Etienne Carriere etienne.carriere@linaro.org wrote:
This change implements a mailbox transport using SMT format for SCMI exchanges. This implementation follows the Linux kernel and SCP-firmware [1] as references implementation for SCMI message processing using SMT format for communication channel meta-data.
Use of mailboxes in SCMI FDT bindings are defined in the Linux kernel DT bindings since v4.17.
Links: [1] https://github.com/ARM-software/SCP-firmware Signed-off-by: Etienne Carriere etienne.carriere@linaro.org Cc: Simon Glass sjg@chromium.org Cc: Peng Fan peng.fan@nxp.com Cc: Sudeep Holla sudeep.holla@arm.com
Changes in v3:
- This is a followup of the SCMI agent patches posted in https://patchwork.ozlabs.org/project/uboot/list/?series=196253 The v3 splits commits and introduces a new uclass as requested.
- This patch implements the same mailbox SCMI agent proposed in v2 but split over few source files.
drivers/firmware/scmi/Kconfig | 6 +- drivers/firmware/scmi/Makefile | 2 + drivers/firmware/scmi/mailbox_agent.c | 107 ++++++++++++++++++++ drivers/firmware/scmi/smt.c | 139 ++++++++++++++++++++++++++ drivers/firmware/scmi/smt.h | 86 ++++++++++++++++ 5 files changed, 338 insertions(+), 2 deletions(-) create mode 100644 drivers/firmware/scmi/mailbox_agent.c create mode 100644 drivers/firmware/scmi/smt.c create mode 100644 drivers/firmware/scmi/smt.h
Reviewed-by: Simon Glass sjg@chromium.org
diff --git a/drivers/firmware/scmi/Kconfig b/drivers/firmware/scmi/Kconfig index 57e2ebbe42..c501bf4943 100644 --- a/drivers/firmware/scmi/Kconfig +++ b/drivers/firmware/scmi/Kconfig @@ -2,7 +2,7 @@ config SCMI_FIRMWARE bool "Enable SCMI support" select FIRMWARE select OF_TRANSLATE
depends on SANDBOX
depends on SANDBOX || DM_MAILBOX help System Control and Management Interface (SCMI) is a communication protocol that defines standard interfaces for power, performance@@ -14,4 +14,6 @@ config SCMI_FIRMWARE or a companion host in the CPU system.
Communications between agent (client) and the SCMI server are
based on message exchange.
based on message exchange. Messages can be exchange over tranportchannels as a mailbox device with some piece of identified sharedmemory.diff --git a/drivers/firmware/scmi/Makefile b/drivers/firmware/scmi/Makefile index 336ea1f2a3..d22f53efe7 100644 --- a/drivers/firmware/scmi/Makefile +++ b/drivers/firmware/scmi/Makefile @@ -1,2 +1,4 @@ obj-y += scmi_agent-uclass.o +obj-y += smt.o +obj-$(CONFIG_DM_MAILBOX) += mailbox_agent.o obj-$(CONFIG_SANDBOX) += sandbox-scmi_agent.o diff --git a/drivers/firmware/scmi/mailbox_agent.c b/drivers/firmware/scmi/mailbox_agent.c new file mode 100644 index 0000000000..9a7b0a5858 --- /dev/null +++ b/drivers/firmware/scmi/mailbox_agent.c @@ -0,0 +1,107 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*
- Copyright (C) 2020 Linaro Limited.
- */
+#include <common.h> +#include <dm.h> +#include <errno.h> +#include <mailbox.h> +#include <scmi_agent.h> +#include <scmi_agent-uclass.h> +#include <dm/devres.h> +#include <linux/compat.h>
+#include "smt.h"
+#define TIMEOUT_US_10MS 10000
+/**
- struct scmi_mbox_channel - Description of an SCMI mailbox transport
- @smt: Shared memory buffer
- @mbox: Mailbox channel description
- @timeout_us: Timeout in microseconds for the mailbox transfer
- */
+struct scmi_mbox_channel {
struct scmi_smt smt;struct mbox_chan mbox;ulong timeout_us;+};
+static struct scmi_mbox_channel *scmi_mbox_get_priv(struct udevice *dev) +{
return (struct scmi_mbox_channel *)dev_get_priv(dev);+}
+static int scmi_mbox_process_msg(struct udevice *dev, struct scmi_msg *msg) +{
struct scmi_mbox_channel *chan = scmi_mbox_get_priv(dev);int ret;ret = scmi_write_msg_to_smt(dev, &chan->smt, msg);if (ret)return ret;/* Give shm addr to mbox in case it is meaningful */ret = mbox_send(&chan->mbox, chan->smt.buf);if (ret) {dev_err(dev, "Message send failed: %d\n", ret);goto out;}/* Receive the response */ret = mbox_recv(&chan->mbox, chan->smt.buf, chan->timeout_us);if (ret) {dev_err(dev, "Response failed: %d, abort\n", ret);goto out;}ret = scmi_read_resp_from_smt(dev, &chan->smt, msg);+out:
scmi_clear_smt_channel(&chan->smt);return ret;+}
+int scmi_mbox_probe(struct udevice *dev) +{
struct scmi_mbox_channel *chan = scmi_mbox_get_priv(dev);int ret;chan->timeout_us = TIMEOUT_US_10MS;ret = mbox_get_by_index(dev, 0, &chan->mbox);if (ret) {dev_err(dev, "Failed to find mailbox: %d\n", ret);goto out;}ret = scmi_dt_get_smt_buffer(dev, &chan->smt);if (ret)dev_err(dev, "Failed to get shm resources: %d\n", ret);+out:
if (ret)devm_kfree(dev, chan);return ret;+}
+static const struct udevice_id scmi_mbox_ids[] = {
{ .compatible = "arm,scmi" },{ }+};
+static const struct scmi_agent_ops scmi_mbox_ops = {
.process_msg = scmi_mbox_process_msg,+};
+U_BOOT_DRIVER(scmi_mbox) = {
.name = "scmi-over-mailbox",.id = UCLASS_SCMI_AGENT,.of_match = scmi_mbox_ids,.priv_auto_alloc_size = sizeof(struct scmi_mbox_channel),.probe = scmi_mbox_probe,.ops = &scmi_mbox_ops,+}; diff --git a/drivers/firmware/scmi/smt.c b/drivers/firmware/scmi/smt.c new file mode 100644 index 0000000000..afe95a4736 --- /dev/null +++ b/drivers/firmware/scmi/smt.c @@ -0,0 +1,139 @@ +// SPDX-License-Identifier: GPL-2.0 +/*
- Copyright (c) 2015-2019, Arm Limited and Contributors. All rights reserved.
- Copyright (C) 2019-2020 Linaro Limited.
- */
+#include <common.h> +#include <cpu_func.h> +#include <dm.h> +#include <errno.h> +#include <scmi_agent.h> +#include <asm/cache.h> +#include <asm/system.h> +#include <dm/ofnode.h> +#include <linux/compat.h> +#include <linux/io.h> +#include <linux/ioport.h>
+#include "smt.h"
+/**
- Get shared memory configuration defined by the referred DT phandle
- Return with a errno compliant value.
- */
+int scmi_dt_get_smt_buffer(struct udevice *dev, struct scmi_smt *smt) +{
int ret;struct ofnode_phandle_args args;struct resource resource;fdt32_t faddr;phys_addr_t paddr;ret = dev_read_phandle_with_args(dev, "shmem", NULL, 0, 0, &args);if (ret)return ret;ret = ofnode_read_resource(args.node, 0, &resource);if (ret)return ret;faddr = cpu_to_fdt32(resource.start);paddr = ofnode_translate_address(args.node, &faddr);smt->size = resource_size(&resource);if (smt->size < sizeof(struct scmi_smt_header)) {dev_err(dev, "Shared memory buffer too small\n");return -EINVAL;}smt->buf = devm_ioremap(dev, paddr, smt->size);if (!smt->buf)return -ENOMEM;+#ifdef __arm__
Should that be CONFIG_ARM ?
if (dcache_status())mmu_set_region_dcache_behaviour((uintptr_t)smt->buf,smt->size, DCACHE_OFF);+#endif
return 0;+}
[..]
Regards, Simon