Hi,
On 7/28/22 20:20, Shyam Sundar S K wrote:
> PMF driver implements the ACPI methods as defined by AMD for PMF Support.
> The ACPI layer acts as a glue that helps in providing the infrastructure
> for OEMs customization.
>
> OEMs can refer to PMF support documentation to decide on the list of
> functions to be supported on their specific platform model.
>
> AMD mandates that PMF ACPI fn0 and fn1 to be implemented which
> provides the set of functions, params and the notifications that
> would be sent to PMF driver so that PMF driver can adapt and
> react.
>
> Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@xxxxxxx>
> ---
> drivers/platform/x86/amd/pmf/Makefile | 2 +-
> drivers/platform/x86/amd/pmf/acpi.c | 182 ++++++++++++++++++++++++++
> drivers/platform/x86/amd/pmf/core.c | 1 +
> drivers/platform/x86/amd/pmf/pmf.h | 32 +++++
> 4 files changed, 216 insertions(+), 1 deletion(-)
> create mode 100644 drivers/platform/x86/amd/pmf/acpi.c
>
> diff --git a/drivers/platform/x86/amd/pmf/Makefile b/drivers/platform/x86/amd/pmf/Makefile
> index 459005f659e5..2617eba773ce 100644
> --- a/drivers/platform/x86/amd/pmf/Makefile
> +++ b/drivers/platform/x86/amd/pmf/Makefile
> @@ -5,4 +5,4 @@
> #
>
> obj-$(CONFIG_AMD_PMF) += amd-pmf.o
> -amd-pmf-objs := core.o
> +amd-pmf-objs := core.o acpi.o
> diff --git a/drivers/platform/x86/amd/pmf/acpi.c b/drivers/platform/x86/amd/pmf/acpi.c
> new file mode 100644
> index 000000000000..bd796d7e1d96
> --- /dev/null
> +++ b/drivers/platform/x86/amd/pmf/acpi.c
> @@ -0,0 +1,182 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * AMD Platform Management Framework Driver
> + *
> + * Copyright (c) 2022, Advanced Micro Devices, Inc.
> + * All Rights Reserved.
> + *
> + * Author: Shyam Sundar S K <Shyam-sundar.S-k@xxxxxxx>
> + */
> +
> +#include <linux/acpi.h>
> +#include "pmf.h"
> +
> +#define APMF_METHOD "\\_SB_.PMF_.APMF"
> +
> +static unsigned long supported_func;
> +
> +static void apmf_if_parse_functions(struct apmf_if_functions *func, u32 mask);
> +
> +static union acpi_object *apmf_if_call(struct apmf_if *apmf_if, int func, struct acpi_buffer *param)
> +{
> + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
> + struct acpi_object_list apmf_if_arg_list;
> + union acpi_object apmf_if_args[2];
> + acpi_status status;
> +
> + apmf_if_arg_list.count = 2;
> + apmf_if_arg_list.pointer = &apmf_if_args[0];
> +
> + apmf_if_args[0].type = ACPI_TYPE_INTEGER;
> + apmf_if_args[0].integer.value = func;
> +
> + if (param) {
> + apmf_if_args[1].type = ACPI_TYPE_BUFFER;
> + apmf_if_args[1].buffer.length = param->length;
> + apmf_if_args[1].buffer.pointer = param->pointer;
> + } else {
> + apmf_if_args[1].type = ACPI_TYPE_INTEGER;
> + apmf_if_args[1].integer.value = 0;
> + }
> +
> + status = acpi_evaluate_object(apmf_if->handle, NULL, &apmf_if_arg_list, &buffer);
> + if (ACPI_FAILURE(status)) {
> + pr_err("PMF: APMF method call failed\n");
> + if (status != AE_NOT_FOUND)
> + kfree(buffer.pointer);
> +
> + return NULL;
> + }
> +
> + return buffer.pointer;
> +}
> +
> +static int apmf_if_call_store_buffer(struct apmf_if *apmf_if, int func, void *dest, size_t out_sz)
> +{
> + union acpi_object *info;
> + size_t size;
> + int err = 0;
> +
> + info = apmf_if_call(apmf_if, func, NULL);
> + if (!info)
> + return -EIO;
> +
> + if (info->type != ACPI_TYPE_BUFFER) {
> + pr_err("object is not a buffer\n");
> + err = -EINVAL;
> + goto out;
> + }
> +
> + if (info->buffer.length < 2) {
> + pr_err("buffer too small\n");
> + err = -EINVAL;
> + goto out;
> + }
> +
> + size = *(u16 *)info->buffer.pointer;
> + if (info->buffer.length < size) {
> + pr_err("buffer smaller then headersize %u < %zu\n",
> + info->buffer.length, size);
> + err = -EINVAL;
> + goto out;
> + }
> +
> + if (size < out_sz) {
> + pr_err("buffer too small %zu\n", size);
> + err = -EINVAL;
> + goto out;
> + }
> +
> + size = out_sz;
> + memcpy(dest, info->buffer.pointer, size);
> +
> +out:
> + kfree(info);
> + return err;
> +}
> +
> +static void apmf_if_parse_functions(struct apmf_if_functions *func, u32 mask)
> +{
> + func->system_params = mask & APMF_FUNC_GET_SYS_PARAMS;
I just noticed that this is not correct, this should be:
func->system_params = mask & BIT(APMF_FUNC_GET_SYS_PARAMS - 1);
Which for APMF_FUNC_GET_SYS_PARAMS happens to be the same, but for
other AMPF_FUNC_* values the difference does matter!
Also this information is duplicated by:
is_apmf_func_supported(APMF_FUNC_GET_SYS_PARAMS) please drop the
apmf_if_functions struct and use is_apmf_func_supported() everywhere.
Note this means that you also will need to drop func->sbios_heartbeat
which does not come from the mask and which is initialized in
a different place rather then inside apmf_if_parse_functions() which
already shows that sbios_hearbeat does not really belong inside
this struct.
Instead of moving the sbios_heartbeat flag, please just directly
use notify_cfg.hb_interval inside apmf_acpi_deinit(). This will also
make the cancel_delayed_work_sync(&pmf_dev->heart_beat) condition
match the queue condition 1:1.
> +}
> +
> +int is_apmf_func_supported(unsigned long index)
> +{
> + /* If bit-n is set, that indicates function n+1 is supported */
> + return ((supported_func & (1 << (index - 1))) != 0);
Please write this as:
return (supported_func & BIT(index - 1)) != 0;
or as:
return !!(supported_func & BIT(index - 1));
> +}
> +
> +static int apmf_if_verify_interface(struct amd_pmf_dev *pdev, struct apmf_if *apmf_if)
> +{
> + struct apmf_verify_interface output;
> + int err;
> +
> + err = apmf_if_call_store_buffer(apmf_if, APMF_FUNC_VERIFY_INTERFACE,
> + &output, sizeof(output));
> + if (err)
> + return err;
> +
> + apmf_if_parse_functions(&apmf_if->func, output.supported_functions);
> + supported_func = output.supported_functions;
> + dev_dbg(pdev->dev, "supported functions:0x%x notifications:0x%x\n",
> + output.supported_functions, output.notification_mask);
> +
> + return 0;
> +}
> +
> +static int apmf_get_system_params(struct apmf_if *apmf_if)
> +{
> + struct apmf_system_params params;
> + int err;
> +
> + if (apmf_if->func.system_params) {
> + err = apmf_if_call_store_buffer(apmf_if, APMF_FUNC_GET_SYS_PARAMS,
> + ¶ms, sizeof(params));
> + if (err)
> + return err;
> + }
> +
> + pr_debug("PMF: system params mask:0x%x flags:0x%x cmd_code:0x%x\n",
> + params.valid_mask,
> + params.flags,
> + params.command_code);
> + params.flags = params.flags & params.valid_mask;
> +
> + return 0;
> +}
> +
> +int apmf_acpi_init(struct amd_pmf_dev *pmf_dev)
> +{
> + acpi_handle apmf_if_handle;
> + struct apmf_if *apmf_if;
> + acpi_status status;
> + int ret;
> +
> + status = acpi_get_handle(NULL, (acpi_string) APMF_METHOD, &apmf_if_handle);
> + if (ACPI_FAILURE(status))
> + return -ENODEV;
> +
> + apmf_if = kzalloc(sizeof(*apmf_if), GFP_KERNEL);
> + if (!apmf_if)
> + goto out;
> +
> + apmf_if->handle = apmf_if_handle;
> +
> + ret = apmf_if_verify_interface(pmf_dev, apmf_if);
> + if (ret) {
> + dev_err(pmf_dev->dev, "APMF verify interface failed :%d\n", ret);
> + kfree(apmf_if);
> + goto out;
> + }
> + pmf_dev->apmf_if = apmf_if;
After dropping the apmf_if_functions sub-struct from amp_if amp_if only contains
an acpi_handle. Please just store the handle (and later on also the struct
apmf_notification_cfg) directly inside struct amd_pmf_dev, this also removes
the need for doing the whole alloc + free + associated error handling dance here.
Regsards,
Hans
> +
> + ret = apmf_get_system_params(apmf_if);
> + if (ret) {
> + dev_err(pmf_dev->dev, "APMF apmf_get_system_params failed :%d\n", ret);
> + kfree(apmf_if);
> + goto out;
> + }
> +
> +out:
> + return ret;
> +}
> diff --git a/drivers/platform/x86/amd/pmf/core.c b/drivers/platform/x86/amd/pmf/core.c
> index aef97965c181..c5002b7bb904 100644
> --- a/drivers/platform/x86/amd/pmf/core.c
> +++ b/drivers/platform/x86/amd/pmf/core.c
> @@ -204,6 +204,7 @@ static int amd_pmf_probe(struct platform_device *pdev)
> if (!dev->regbase)
> return -ENOMEM;
>
> + apmf_acpi_init(dev);
> platform_set_drvdata(pdev, dev);
>
> mutex_init(&dev->lock);
> diff --git a/drivers/platform/x86/amd/pmf/pmf.h b/drivers/platform/x86/amd/pmf/pmf.h
> index 1c2e942e5096..08c6bc0e2b42 100644
> --- a/drivers/platform/x86/amd/pmf/pmf.h
> +++ b/drivers/platform/x86/amd/pmf/pmf.h
> @@ -11,6 +11,12 @@
> #ifndef PMF_H
> #define PMF_H
>
> +#include <linux/acpi.h>
> +
> +/* APMF Functions */
> +#define APMF_FUNC_VERIFY_INTERFACE 0
> +#define APMF_FUNC_GET_SYS_PARAMS 1
> +
> /* Message Definitions */
> #define SET_SPL 0x03 /* SPL: Sustained Power Limit */
> #define SET_SPPT 0x05 /* SPPT: Slow Package Power Tracking */
> @@ -30,6 +36,30 @@
> #define GET_STT_LIMIT_APU 0x20
> #define GET_STT_LIMIT_HS2 0x21
>
> +/* AMD PMF BIOS interfaces */
> +struct apmf_if_functions {
> + bool system_params;
> +};
> +
> +struct apmf_if {
> + acpi_handle handle;
> + struct apmf_if_functions func;
> +};
> +
> +struct apmf_verify_interface {
> + u16 size;
> + u16 version;
> + u32 notification_mask;
> + u32 supported_functions;
> +} __packed;
> +
> +struct apmf_system_params {
> + u16 size;
> + u32 valid_mask;
> + u32 flags;
> + u8 command_code;
> +} __packed;
> +
> struct amd_pmf_dev {
> void __iomem *regbase;
> void __iomem *smu_virt_addr;
> @@ -37,10 +67,12 @@ struct amd_pmf_dev {
> u32 base_addr;
> u32 cpu_id;
> struct device *dev;
> + struct apmf_if *apmf_if;
> struct mutex lock; /* protects the PMF interface */
> };
>
> /* Core Layer */
> +int apmf_acpi_init(struct amd_pmf_dev *pmf_dev);
> int amd_pmf_send_cmd(struct amd_pmf_dev *dev, u8 message, bool get, u32 arg, u32 *data);
>
> #endif /* PMF_H */
