[PATCH v10 08/12] mfd: intel-peci-client: Add PECI client driver

From: Jae Hyun Yoo
Date: Mon Jan 07 2019 - 16:42:04 EST


This commit adds PECI client driver.

Cc: Lee Jones <lee.jones@xxxxxxxxxx>
Cc: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Cc: Rob Herring <robh+dt@xxxxxxxxxx>
Cc: Andrew Jeffery <andrew@xxxxxxxx>
Cc: James Feist <james.feist@xxxxxxxxxxxxxxx>
Cc: Jason M Biils <jason.m.bills@xxxxxxxxxxxxxxx>
Cc: Joel Stanley <joel@xxxxxxxxx>
Cc: Vernon Mauery <vernon.mauery@xxxxxxxxxxxxxxx>
Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@xxxxxxxxxxxxxxx>
---
drivers/mfd/Kconfig | 14 +++
drivers/mfd/Makefile | 1 +
drivers/mfd/intel-peci-client.c | 143 ++++++++++++++++++++++++++
include/linux/mfd/intel-peci-client.h | 108 +++++++++++++++++++
4 files changed, 266 insertions(+)
create mode 100644 drivers/mfd/intel-peci-client.c
create mode 100644 include/linux/mfd/intel-peci-client.h

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 8c5dfdce4326..d021aa8dfa99 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -604,6 +604,20 @@ config MFD_INTEL_MSIC
Passage) chip. This chip embeds audio, battery, GPIO, etc.
devices used in Intel Medfield platforms.

+config MFD_INTEL_PECI_CLIENT
+ bool "Intel PECI client"
+ depends on (PECI || COMPILE_TEST)
+ select MFD_CORE
+ help
+ If you say yes to this option, support will be included for the
+ Intel PECI (Platform Environment Control Interface) client. PECI is a
+ one-wire bus interface that provides a communication channel from PECI
+ clients in Intel processors and chipset components to external
+ monitoring or control devices.
+
+ Additional drivers must be enabled in order to use the functionality
+ of the device.
+
config MFD_IPAQ_MICRO
bool "Atmel Micro ASIC (iPAQ h3100/h3600/h3700) Support"
depends on SA1100_H3100 || SA1100_H3600
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 12980a4ad460..b8c1da8e748b 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -204,6 +204,7 @@ obj-$(CONFIG_MFD_INTEL_LPSS) += intel-lpss.o
obj-$(CONFIG_MFD_INTEL_LPSS_PCI) += intel-lpss-pci.o
obj-$(CONFIG_MFD_INTEL_LPSS_ACPI) += intel-lpss-acpi.o
obj-$(CONFIG_MFD_INTEL_MSIC) += intel_msic.o
+obj-$(CONFIG_MFD_INTEL_PECI_CLIENT) += intel-peci-client.o
obj-$(CONFIG_MFD_PALMAS) += palmas.o
obj-$(CONFIG_MFD_VIPERBOARD) += viperboard.o
obj-$(CONFIG_MFD_RC5T583) += rc5t583.o rc5t583-irq.o
diff --git a/drivers/mfd/intel-peci-client.c b/drivers/mfd/intel-peci-client.c
new file mode 100644
index 000000000000..d62442438512
--- /dev/null
+++ b/drivers/mfd/intel-peci-client.c
@@ -0,0 +1,143 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2018-2019 Intel Corporation
+
+#include <linux/bitfield.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/intel-peci-client.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/peci.h>
+
+#define CPU_ID_MODEL_MASK GENMASK(7, 4)
+#define CPU_ID_FAMILY_MASK GENMASK(11, 8)
+#define CPU_ID_EXT_MODEL_MASK GENMASK(19, 16)
+#define CPU_ID_EXT_FAMILY_MASK GENMASK(27, 20)
+
+#define LOWER_NIBBLE_MASK GENMASK(3, 0)
+#define UPPER_NIBBLE_MASK GENMASK(7, 4)
+#define LOWER_BYTE_MASK GENMASK(7, 0)
+#define UPPER_BYTE_MASK GENMASK(16, 8)
+
+static struct mfd_cell peci_functions[] = {
+ { .name = "peci-cputemp", },
+ { .name = "peci-dimmtemp", },
+ /* TODO: Add additional PECI sideband functions into here */
+};
+
+static const struct cpu_gen_info cpu_gen_info_table[] = {
+ { /* Haswell Xeon */
+ .family = 6, /* Family code */
+ .model = INTEL_FAM6_HASWELL_X,
+ .core_max = CORE_MAX_ON_HSX,
+ .chan_rank_max = CHAN_RANK_MAX_ON_HSX,
+ .dimm_idx_max = DIMM_IDX_MAX_ON_HSX },
+ { /* Broadwell Xeon */
+ .family = 6, /* Family code */
+ .model = INTEL_FAM6_BROADWELL_X,
+ .core_max = CORE_MAX_ON_BDX,
+ .chan_rank_max = CHAN_RANK_MAX_ON_BDX,
+ .dimm_idx_max = DIMM_IDX_MAX_ON_BDX },
+ { /* Skylake Xeon */
+ .family = 6, /* Family code */
+ .model = INTEL_FAM6_SKYLAKE_X,
+ .core_max = CORE_MAX_ON_SKX,
+ .chan_rank_max = CHAN_RANK_MAX_ON_SKX,
+ .dimm_idx_max = DIMM_IDX_MAX_ON_SKX },
+};
+
+static int peci_client_get_cpu_gen_info(struct peci_client_manager *priv)
+{
+ struct device *dev = &priv->client->dev;
+ u32 cpu_id;
+ u16 family;
+ u8 model;
+ int ret;
+ int i;
+
+ ret = peci_get_cpu_id(priv->client->adapter, priv->client->addr,
+ &cpu_id);
+ if (ret)
+ return ret;
+
+ family = FIELD_PREP(LOWER_BYTE_MASK,
+ FIELD_GET(CPU_ID_FAMILY_MASK, cpu_id)) |
+ FIELD_PREP(UPPER_BYTE_MASK,
+ FIELD_GET(CPU_ID_EXT_FAMILY_MASK, cpu_id));
+ model = FIELD_PREP(LOWER_NIBBLE_MASK,
+ FIELD_GET(CPU_ID_MODEL_MASK, cpu_id)) |
+ FIELD_PREP(UPPER_NIBBLE_MASK,
+ FIELD_GET(CPU_ID_EXT_MODEL_MASK, cpu_id));
+
+ for (i = 0; i < ARRAY_SIZE(cpu_gen_info_table); i++) {
+ const struct cpu_gen_info *cpu_info = &cpu_gen_info_table[i];
+
+ if (family == cpu_info->family && model == cpu_info->model) {
+ priv->gen_info = cpu_info;
+ break;
+ }
+ }
+
+ if (!priv->gen_info) {
+ dev_err(dev, "Can't support this CPU: 0x%x\n", cpu_id);
+ ret = -ENODEV;
+ }
+
+ return ret;
+}
+
+static int peci_client_probe(struct peci_client *client)
+{
+ struct device *dev = &client->dev;
+ struct peci_client_manager *priv;
+ uint cpu_no;
+ int ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ dev_set_drvdata(dev, priv);
+ priv->client = client;
+ cpu_no = client->addr - PECI_BASE_ADDR;
+
+ ret = peci_client_get_cpu_gen_info(priv);
+ if (ret)
+ return ret;
+
+ ret = devm_mfd_add_devices(dev, cpu_no, peci_functions,
+ ARRAY_SIZE(peci_functions), NULL, 0, NULL);
+ if (ret < 0) {
+ dev_err(dev, "Failed to register child devices: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+#if IS_ENABLED(CONFIG_OF)
+static const struct of_device_id peci_client_of_table[] = {
+ { .compatible = "intel,peci-client" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, peci_client_of_table);
+#endif /* CONFIG_OF */
+
+static const struct peci_device_id peci_client_ids[] = {
+ { .name = "peci-client" },
+ { }
+};
+MODULE_DEVICE_TABLE(peci, peci_client_ids);
+
+static struct peci_driver peci_client_driver = {
+ .probe = peci_client_probe,
+ .id_table = peci_client_ids,
+ .driver = {
+ .name = "peci-client",
+ .of_match_table = of_match_ptr(peci_client_of_table),
+ },
+};
+module_peci_driver(peci_client_driver);
+
+MODULE_AUTHOR("Jae Hyun Yoo <jae.hyun.yoo@xxxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("PECI client driver");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/mfd/intel-peci-client.h b/include/linux/mfd/intel-peci-client.h
new file mode 100644
index 000000000000..dd5eb36cca75
--- /dev/null
+++ b/include/linux/mfd/intel-peci-client.h
@@ -0,0 +1,108 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (c) 2018-2019 Intel Corporation */
+
+#ifndef __LINUX_MFD_INTEL_PECI_CLIENT_H
+#define __LINUX_MFD_INTEL_PECI_CLIENT_H
+
+#include <linux/peci.h>
+
+#if IS_ENABLED(CONFIG_X86)
+#include <asm/intel-family.h>
+#else
+/**
+ * Architectures other than x86 cannot include the header file so define these
+ * at here. These are needed for detecting type of client x86 CPUs behind a PECI
+ * connection.
+ */
+#define INTEL_FAM6_HASWELL_X 0x3F
+#define INTEL_FAM6_BROADWELL_X 0x4F
+#define INTEL_FAM6_SKYLAKE_X 0x55
+#endif
+
+#define CORE_MAX_ON_HSX 18 /* Max number of cores on Haswell */
+#define CHAN_RANK_MAX_ON_HSX 8 /* Max number of channel ranks on Haswell */
+#define DIMM_IDX_MAX_ON_HSX 3 /* Max DIMM index per channel on Haswell */
+
+#define CORE_MAX_ON_BDX 24 /* Max number of cores on Broadwell */
+#define CHAN_RANK_MAX_ON_BDX 4 /* Max number of channel ranks on Broadwell */
+#define DIMM_IDX_MAX_ON_BDX 3 /* Max DIMM index per channel on Broadwell */
+
+#define CORE_MAX_ON_SKX 28 /* Max number of cores on Skylake */
+#define CHAN_RANK_MAX_ON_SKX 6 /* Max number of channel ranks on Skylake */
+#define DIMM_IDX_MAX_ON_SKX 2 /* Max DIMM index per channel on Skylake */
+
+#define CORE_NUMS_MAX CORE_MAX_ON_SKX
+#define CHAN_RANK_MAX CHAN_RANK_MAX_ON_HSX
+#define DIMM_IDX_MAX DIMM_IDX_MAX_ON_HSX
+#define DIMM_NUMS_MAX (CHAN_RANK_MAX * DIMM_IDX_MAX)
+
+/**
+ * struct cpu_gen_info - CPU generation specific information
+ * @family: CPU family ID
+ * @model: CPU model
+ * @core_max: max number of cores
+ * @chan_rank_max: max number of channel ranks
+ * @dimm_idx_max: max number of DIMM indices
+ *
+ * CPU generation specific information to identify maximum number of cores and
+ * DIMM slots.
+ */
+struct cpu_gen_info {
+ u16 family;
+ u8 model;
+ uint core_max;
+ uint chan_rank_max;
+ uint dimm_idx_max;
+};
+
+/**
+ * struct peci_client_manager - PECI client manager information
+ * @client; pointer to the PECI client
+ * @name: PECI client manager name
+ * @gen_info: CPU generation info of the detected CPU
+ *
+ * PECI client manager information for managing PECI sideband functions on a CPU
+ * client.
+ */
+struct peci_client_manager {
+ struct peci_client *client;
+ char name[PECI_NAME_SIZE];
+ const struct cpu_gen_info *gen_info;
+};
+
+/**
+ * peci_client_read_package_config - read from the Package Configuration Space
+ * @priv: driver private data structure
+ * @index: encoding index for the requested service
+ * @param: parameter to specify the exact data being requested
+ * @data: data buffer to store the result
+ * Context: can sleep
+ *
+ * A generic PECI command that provides read access to the
+ * "Package Configuration Space" that is maintained by the PCU, including
+ * various power and thermal management functions. Typical PCS read services
+ * supported by the processor may include access to temperature data, energy
+ * status, run time information, DIMM temperatures and so on.
+ *
+ * Return: zero on success, else a negative error code.
+ */
+static inline int
+peci_client_read_package_config(struct peci_client_manager *priv,
+ u8 index, u16 param, u8 *data)
+{
+ struct peci_rd_pkg_cfg_msg msg;
+ int rc;
+
+ msg.addr = priv->client->addr;
+ msg.index = index;
+ msg.param = param;
+ msg.rx_len = 4;
+
+ rc = peci_command(priv->client->adapter, PECI_CMD_RD_PKG_CFG, &msg);
+ if (!rc)
+ memcpy(data, msg.pkg_config, 4);
+
+ return rc;
+}
+
+#endif /* __LINUX_MFD_INTEL_PECI_CLIENT_H */
--
2.20.1