[PATCH net-next 1/6] platform/x86: intel_pmc_core: Add IPC mailbox accessor function and add SoC register access
Hans de Goede
hdegoede at redhat.com
Thu Jun 22 01:18:25 PDT 2023
Hi,
On 6/22/23 06:19, Choong Yong Liang wrote:
> From: "David E. Box" <david.e.box at linux.intel.com>
>
> - Exports intel_pmc_core_ipc() for host access to the PMC IPC mailbox
> - Add support to use IPC command allows host to access SoC registers
> through PMC firmware that are otherwise inaccessible to the host due to
> security policies.
>
> Signed-off-by: David E. Box <david.e.box at linux.intel.com>
> Signed-off-by: Chao Qin <chao.qin at intel.com>
> Signed-off-by: Choong Yong Liang <yong.liang.choong at linux.intel.com>
This seem to be 2 patches in 1:
1. Move core.h to include/linux/intel_pmc_core.h
2. The actual adding of IPC mailbox accessor function and add SoC register access
I wonder if you really need to move the entire core.h ?
IMHO it would be better to just add a new header with just the bits
which you actually need to export the desired functionality.
If you do believe that you really need to move core.h please split
this into 2 separate patches and please place the header in a x86
specific place, e.g. : include/linux/platform_data/x86/
Also note that a somewhat big refactor, to add support for
multiple PMCs for Meteor Lake is on its way to linux-next.
Currently this is available in my review-hans branch:
https://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86.git/log/?h=review-hans
Please base a next version of this on this.
There also is the question of how to merge this. Assuming this is
ready for merging once 6.5-rc1 is out then I can merge this intel_pmc_core
change into an immutable branch and send a pull-req to the net folks
for this.
Regards,
Hans
> ---
> MAINTAINERS | 1 +
> drivers/platform/x86/intel/pmc/adl.c | 2 +-
> drivers/platform/x86/intel/pmc/cnp.c | 2 +-
> drivers/platform/x86/intel/pmc/core.c | 63 ++++++++++++++++++-
> drivers/platform/x86/intel/pmc/icl.c | 2 +-
> drivers/platform/x86/intel/pmc/mtl.c | 2 +-
> drivers/platform/x86/intel/pmc/spt.c | 2 +-
> drivers/platform/x86/intel/pmc/tgl.c | 2 +-
> .../core.h => include/linux/intel_pmc_core.h | 27 +++++++-
> 9 files changed, 95 insertions(+), 8 deletions(-)
> rename drivers/platform/x86/intel/pmc/core.h => include/linux/intel_pmc_core.h (95%)
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index cb14589d14ab..bdb08a79a5f8 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -10581,6 +10581,7 @@ L: platform-driver-x86 at vger.kernel.org
> S: Maintained
> F: Documentation/ABI/testing/sysfs-platform-intel-pmc
> F: drivers/platform/x86/intel/pmc/
> +F: include/linux/intel_pmc_core*
>
> INTEL PMIC GPIO DRIVERS
> M: Andy Shevchenko <andy at kernel.org>
> diff --git a/drivers/platform/x86/intel/pmc/adl.c b/drivers/platform/x86/intel/pmc/adl.c
> index 5cbd40979f2a..b6a376c536c0 100644
> --- a/drivers/platform/x86/intel/pmc/adl.c
> +++ b/drivers/platform/x86/intel/pmc/adl.c
> @@ -8,7 +8,7 @@
> *
> */
>
> -#include "core.h"
> +#include <linux/intel_pmc_core.h>
>
> /* Alder Lake: PGD PFET Enable Ack Status Register(s) bitmap */
> const struct pmc_bit_map adl_pfear_map[] = {
> diff --git a/drivers/platform/x86/intel/pmc/cnp.c b/drivers/platform/x86/intel/pmc/cnp.c
> index 7fb38815c4eb..504034cc5ec3 100644
> --- a/drivers/platform/x86/intel/pmc/cnp.c
> +++ b/drivers/platform/x86/intel/pmc/cnp.c
> @@ -8,7 +8,7 @@
> *
> */
>
> -#include "core.h"
> +#include <linux/intel_pmc_core.h>
>
> /* Cannon Lake: PGD PFET Enable Ack Status Register(s) bitmap */
> const struct pmc_bit_map cnp_pfear_map[] = {
> diff --git a/drivers/platform/x86/intel/pmc/core.c b/drivers/platform/x86/intel/pmc/core.c
> index da6e7206d38b..0d60763c5144 100644
> --- a/drivers/platform/x86/intel/pmc/core.c
> +++ b/drivers/platform/x86/intel/pmc/core.c
> @@ -16,6 +16,7 @@
> #include <linux/delay.h>
> #include <linux/dmi.h>
> #include <linux/io.h>
> +#include <linux/intel_pmc_core.h>
> #include <linux/module.h>
> #include <linux/pci.h>
> #include <linux/slab.h>
> @@ -26,7 +27,9 @@
> #include <asm/msr.h>
> #include <asm/tsc.h>
>
> -#include "core.h"
> +#define PMC_IPCS_PARAM_COUNT 7
> +
> +static const struct x86_cpu_id *pmc_cpu_id;
>
> /* Maximum number of modes supported by platfoms that has low power mode capability */
> const char *pmc_lpm_modes[] = {
> @@ -53,6 +56,63 @@ const struct pmc_bit_map msr_map[] = {
> {}
> };
>
> +int intel_pmc_core_ipc(struct pmc_ipc_cmd *ipc_cmd, u32 *rbuf)
> +{
> + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
> + union acpi_object params[PMC_IPCS_PARAM_COUNT] = {
> + {.type = ACPI_TYPE_INTEGER,},
> + {.type = ACPI_TYPE_INTEGER,},
> + {.type = ACPI_TYPE_INTEGER,},
> + {.type = ACPI_TYPE_INTEGER,},
> + {.type = ACPI_TYPE_INTEGER,},
> + {.type = ACPI_TYPE_INTEGER,},
> + {.type = ACPI_TYPE_INTEGER,},
> + };
> + struct acpi_object_list arg_list = { PMC_IPCS_PARAM_COUNT, params };
> + union acpi_object *obj;
> + int status;
> +
> + if (!pmc_cpu_id || !ipc_cmd || !rbuf)
> + return -EINVAL;
> +
> + /*
> + * 0: IPC Command
> + * 1: IPC Sub Command
> + * 2: Size
> + * 3-6: Write Buffer for offset
> + */
> + params[0].integer.value = ipc_cmd->cmd;
> + params[1].integer.value = ipc_cmd->sub_cmd;
> + params[2].integer.value = ipc_cmd->size;
> + params[3].integer.value = ipc_cmd->wbuf[0];
> + params[4].integer.value = ipc_cmd->wbuf[1];
> + params[5].integer.value = ipc_cmd->wbuf[2];
> + params[6].integer.value = ipc_cmd->wbuf[3];
> +
> + status = acpi_evaluate_object(NULL, "\\IPCS", &arg_list, &buffer);
> + if (ACPI_FAILURE(status))
> + return -ENODEV;
> +
> + obj = buffer.pointer;
> + /* Check if the number of elements in package is 5 */
> + if (obj && obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 5) {
> + const union acpi_object *objs = obj->package.elements;
> +
> + if ((u8)objs[0].integer.value != 0)
> + return -EINVAL;
> +
> + rbuf[0] = objs[1].integer.value;
> + rbuf[1] = objs[2].integer.value;
> + rbuf[2] = objs[3].integer.value;
> + rbuf[3] = objs[4].integer.value;
> + } else {
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(intel_pmc_core_ipc);
> +
> static inline u32 pmc_core_reg_read(struct pmc_dev *pmcdev, int reg_offset)
> {
> return readl(pmcdev->regbase + reg_offset);
> @@ -1130,6 +1190,7 @@ static int pmc_core_probe(struct platform_device *pdev)
> mutex_init(&pmcdev->lock);
> core_init(pmcdev);
>
> + pmc_cpu_id = cpu_id;
>
> if (lpit_read_residency_count_address(&slp_s0_addr)) {
> pmcdev->base_addr = PMC_BASE_ADDR_DEFAULT;
> diff --git a/drivers/platform/x86/intel/pmc/icl.c b/drivers/platform/x86/intel/pmc/icl.c
> index 2f11b1a6daeb..f18048ff9382 100644
> --- a/drivers/platform/x86/intel/pmc/icl.c
> +++ b/drivers/platform/x86/intel/pmc/icl.c
> @@ -8,7 +8,7 @@
> *
> */
>
> -#include "core.h"
> +#include <linux/intel_pmc_core.h>
>
> const struct pmc_bit_map icl_pfear_map[] = {
> {"RES_65", BIT(0)},
> diff --git a/drivers/platform/x86/intel/pmc/mtl.c b/drivers/platform/x86/intel/pmc/mtl.c
> index e8cc156412ce..7897f5fe9881 100644
> --- a/drivers/platform/x86/intel/pmc/mtl.c
> +++ b/drivers/platform/x86/intel/pmc/mtl.c
> @@ -9,7 +9,7 @@
> */
>
> #include <linux/pci.h>
> -#include "core.h"
> +#include <linux/intel_pmc_core.h>
>
> const struct pmc_reg_map mtl_reg_map = {
> .pfear_sts = ext_tgl_pfear_map,
> diff --git a/drivers/platform/x86/intel/pmc/spt.c b/drivers/platform/x86/intel/pmc/spt.c
> index e16982236778..95ce490cf5d6 100644
> --- a/drivers/platform/x86/intel/pmc/spt.c
> +++ b/drivers/platform/x86/intel/pmc/spt.c
> @@ -8,7 +8,7 @@
> *
> */
>
> -#include "core.h"
> +#include <linux/intel_pmc_core.h>
>
> const struct pmc_bit_map spt_pll_map[] = {
> {"MIPI PLL", SPT_PMC_BIT_MPHY_CMN_LANE0},
> diff --git a/drivers/platform/x86/intel/pmc/tgl.c b/drivers/platform/x86/intel/pmc/tgl.c
> index c245ada849d0..a1719d809497 100644
> --- a/drivers/platform/x86/intel/pmc/tgl.c
> +++ b/drivers/platform/x86/intel/pmc/tgl.c
> @@ -8,7 +8,7 @@
> *
> */
>
> -#include "core.h"
> +#include <linux/intel_pmc_core.h>
>
> #define ACPI_S0IX_DSM_UUID "57a6512e-3979-4e9d-9708-ff13b2508972"
> #define ACPI_GET_LOW_MODE_REGISTERS 1
> diff --git a/drivers/platform/x86/intel/pmc/core.h b/include/linux/intel_pmc_core.h
> similarity index 95%
> rename from drivers/platform/x86/intel/pmc/core.h
> rename to include/linux/intel_pmc_core.h
> index 9ca9b9746719..82810e8b92a2 100644
> --- a/drivers/platform/x86/intel/pmc/core.h
> +++ b/include/linux/intel_pmc_core.h
> @@ -250,7 +250,16 @@ enum ppfear_regs {
> #define MTL_LPM_STATUS_OFFSET 0x1700
> #define MTL_LPM_LIVE_STATUS_OFFSET 0x175C
>
> -extern const char *pmc_lpm_modes[];
> +#define IPC_SOC_REGISTER_ACCESS 0xAA
> +#define IPC_SOC_SUB_CMD_READ 0x00
> +#define IPC_SOC_SUB_CMD_WRITE 0x01
> +
> +struct pmc_ipc_cmd {
> + u32 cmd;
> + u32 sub_cmd;
> + u32 size;
> + u32 wbuf[4];
> +};
>
> struct pmc_bit_map {
> const char *name;
> @@ -427,4 +436,20 @@ static const struct file_operations __name ## _fops = { \
> .release = single_release, \
> }
>
> +#if IS_ENABLED(CONFIG_INTEL_PMC_CORE)
> +/**
> + * intel_pmc_core_ipc() - PMC IPC Mailbox accessor
> + * @ipc_cmd: struct pmc_ipc_cmd prepared with input to send
> + * @rbuf: Allocated u32[4] array for returned IPC data
> + *
> + * Return: 0 on success. Non-zero on mailbox error
> + */
> +int intel_pmc_core_ipc(struct pmc_ipc_cmd *ipc_cmd, u32 *rbuf);
> +#else
> +static inline int intel_pmc_core_ipc(struct pmc_ipc_cmd *ipc_cmd, u32 *rbuf)
> +{
> + return -ENODEV;
> +}
> +#endif /* CONFIG_INTEL_PMC_CORE */
> +
> #endif /* PMC_CORE_H */
More information about the linux-arm-kernel
mailing list