2021-06-08 17:07:03

by M Chetan Kumar

[permalink] [raw]
Subject: [PATCH V4 03/16] net: iosm: mmio scratchpad

1) Initializes the Scratchpad region for Host-Device communication.
2) Exposes device capabilities like chip info and device execution
stages.

Signed-off-by: M Chetan Kumar <[email protected]>
---
v4: no change.
v3: no change.
v2:
* Removed space around the : for the bitfields.
* Return proper error code instead of returning -1.
---
drivers/net/wwan/iosm/iosm_ipc_mmio.c | 223 ++++++++++++++++++++++++++
drivers/net/wwan/iosm/iosm_ipc_mmio.h | 193 ++++++++++++++++++++++
2 files changed, 416 insertions(+)
create mode 100644 drivers/net/wwan/iosm/iosm_ipc_mmio.c
create mode 100644 drivers/net/wwan/iosm/iosm_ipc_mmio.h

diff --git a/drivers/net/wwan/iosm/iosm_ipc_mmio.c b/drivers/net/wwan/iosm/iosm_ipc_mmio.c
new file mode 100644
index 000000000000..06c94b1720b6
--- /dev/null
+++ b/drivers/net/wwan/iosm/iosm_ipc_mmio.c
@@ -0,0 +1,223 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020-21 Intel Corporation.
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/io-64-nonatomic-lo-hi.h>
+#include <linux/slab.h>
+
+#include "iosm_ipc_mmio.h"
+
+/* Definition of MMIO offsets
+ * note that MMIO_CI offsets are relative to end of chip info structure
+ */
+
+/* MMIO chip info size in bytes */
+#define MMIO_CHIP_INFO_SIZE 60
+
+/* CP execution stage */
+#define MMIO_OFFSET_EXECUTION_STAGE 0x00
+
+/* Boot ROM Chip Info struct */
+#define MMIO_OFFSET_CHIP_INFO 0x04
+
+#define MMIO_OFFSET_ROM_EXIT_CODE 0x40
+
+#define MMIO_OFFSET_PSI_ADDRESS 0x54
+
+#define MMIO_OFFSET_PSI_SIZE 0x5C
+
+#define MMIO_OFFSET_IPC_STATUS 0x60
+
+#define MMIO_OFFSET_CONTEXT_INFO 0x64
+
+#define MMIO_OFFSET_BASE_ADDR 0x6C
+
+#define MMIO_OFFSET_END_ADDR 0x74
+
+#define MMIO_OFFSET_CP_VERSION 0xF0
+
+#define MMIO_OFFSET_CP_CAPABILITIES 0xF4
+
+/* Timeout in 50 msec to wait for the modem boot code to write a valid
+ * execution stage into mmio area
+ */
+#define IPC_MMIO_EXEC_STAGE_TIMEOUT 50
+
+/* check if exec stage has one of the valid values */
+static bool ipc_mmio_is_valid_exec_stage(enum ipc_mem_exec_stage stage)
+{
+ switch (stage) {
+ case IPC_MEM_EXEC_STAGE_BOOT:
+ case IPC_MEM_EXEC_STAGE_PSI:
+ case IPC_MEM_EXEC_STAGE_EBL:
+ case IPC_MEM_EXEC_STAGE_RUN:
+ case IPC_MEM_EXEC_STAGE_CRASH:
+ case IPC_MEM_EXEC_STAGE_CD_READY:
+ return true;
+ default:
+ return false;
+ }
+}
+
+void ipc_mmio_update_cp_capability(struct iosm_mmio *ipc_mmio)
+{
+ u32 cp_cap;
+ unsigned int ver;
+
+ ver = ipc_mmio_get_cp_version(ipc_mmio);
+ cp_cap = readl(ipc_mmio->base + ipc_mmio->offset.cp_capability);
+
+ ipc_mmio->has_mux_lite = (ver >= IOSM_CP_VERSION) &&
+ !(cp_cap & DL_AGGR) && !(cp_cap & UL_AGGR);
+
+ ipc_mmio->has_ul_flow_credit =
+ (ver >= IOSM_CP_VERSION) && (cp_cap & UL_FLOW_CREDIT);
+}
+
+struct iosm_mmio *ipc_mmio_init(void __iomem *mmio, struct device *dev)
+{
+ struct iosm_mmio *ipc_mmio = kzalloc(sizeof(*ipc_mmio), GFP_KERNEL);
+ int retries = IPC_MMIO_EXEC_STAGE_TIMEOUT;
+ enum ipc_mem_exec_stage stage;
+
+ if (!ipc_mmio)
+ return NULL;
+
+ ipc_mmio->dev = dev;
+
+ ipc_mmio->base = mmio;
+
+ ipc_mmio->offset.exec_stage = MMIO_OFFSET_EXECUTION_STAGE;
+
+ /* Check for a valid execution stage to make sure that the boot code
+ * has correctly initialized the MMIO area.
+ */
+ do {
+ stage = ipc_mmio_get_exec_stage(ipc_mmio);
+ if (ipc_mmio_is_valid_exec_stage(stage))
+ break;
+
+ msleep(20);
+ } while (retries-- > 0);
+
+ if (!retries) {
+ dev_err(ipc_mmio->dev, "invalid exec stage %X", stage);
+ goto init_fail;
+ }
+
+ ipc_mmio->offset.chip_info = MMIO_OFFSET_CHIP_INFO;
+
+ /* read chip info size and version from chip info structure */
+ ipc_mmio->chip_info_version =
+ ioread8(ipc_mmio->base + ipc_mmio->offset.chip_info);
+
+ /* Increment of 2 is needed as the size value in the chip info
+ * excludes the version and size field, which are always present
+ */
+ ipc_mmio->chip_info_size =
+ ioread8(ipc_mmio->base + ipc_mmio->offset.chip_info + 1) + 2;
+
+ if (ipc_mmio->chip_info_size != MMIO_CHIP_INFO_SIZE) {
+ dev_err(ipc_mmio->dev, "Unexpected Chip Info");
+ goto init_fail;
+ }
+
+ ipc_mmio->offset.rom_exit_code = MMIO_OFFSET_ROM_EXIT_CODE;
+
+ ipc_mmio->offset.psi_address = MMIO_OFFSET_PSI_ADDRESS;
+ ipc_mmio->offset.psi_size = MMIO_OFFSET_PSI_SIZE;
+ ipc_mmio->offset.ipc_status = MMIO_OFFSET_IPC_STATUS;
+ ipc_mmio->offset.context_info = MMIO_OFFSET_CONTEXT_INFO;
+ ipc_mmio->offset.ap_win_base = MMIO_OFFSET_BASE_ADDR;
+ ipc_mmio->offset.ap_win_end = MMIO_OFFSET_END_ADDR;
+
+ ipc_mmio->offset.cp_version = MMIO_OFFSET_CP_VERSION;
+ ipc_mmio->offset.cp_capability = MMIO_OFFSET_CP_CAPABILITIES;
+
+ return ipc_mmio;
+
+init_fail:
+ kfree(ipc_mmio);
+ return NULL;
+}
+
+enum ipc_mem_exec_stage ipc_mmio_get_exec_stage(struct iosm_mmio *ipc_mmio)
+{
+ if (!ipc_mmio)
+ return IPC_MEM_EXEC_STAGE_INVALID;
+
+ return (enum ipc_mem_exec_stage)readl(ipc_mmio->base +
+ ipc_mmio->offset.exec_stage);
+}
+
+void ipc_mmio_copy_chip_info(struct iosm_mmio *ipc_mmio, void *dest,
+ size_t size)
+{
+ if (ipc_mmio && dest)
+ memcpy_fromio(dest, ipc_mmio->base + ipc_mmio->offset.chip_info,
+ size);
+}
+
+enum ipc_mem_device_ipc_state ipc_mmio_get_ipc_state(struct iosm_mmio *ipc_mmio)
+{
+ if (!ipc_mmio)
+ return IPC_MEM_DEVICE_IPC_INVALID;
+
+ return (enum ipc_mem_device_ipc_state)
+ readl(ipc_mmio->base + ipc_mmio->offset.ipc_status);
+}
+
+enum rom_exit_code ipc_mmio_get_rom_exit_code(struct iosm_mmio *ipc_mmio)
+{
+ if (!ipc_mmio)
+ return IMEM_ROM_EXIT_FAIL;
+
+ return (enum rom_exit_code)readl(ipc_mmio->base +
+ ipc_mmio->offset.rom_exit_code);
+}
+
+void ipc_mmio_config(struct iosm_mmio *ipc_mmio)
+{
+ if (!ipc_mmio)
+ return;
+
+ /* AP memory window (full window is open and active so that modem checks
+ * each AP address) 0 means don't check on modem side.
+ */
+ iowrite64_lo_hi(0, ipc_mmio->base + ipc_mmio->offset.ap_win_base);
+ iowrite64_lo_hi(0, ipc_mmio->base + ipc_mmio->offset.ap_win_end);
+
+ iowrite64_lo_hi(ipc_mmio->context_info_addr,
+ ipc_mmio->base + ipc_mmio->offset.context_info);
+}
+
+void ipc_mmio_set_psi_addr_and_size(struct iosm_mmio *ipc_mmio, dma_addr_t addr,
+ u32 size)
+{
+ if (!ipc_mmio)
+ return;
+
+ iowrite64_lo_hi(addr, ipc_mmio->base + ipc_mmio->offset.psi_address);
+ writel(size, ipc_mmio->base + ipc_mmio->offset.psi_size);
+}
+
+void ipc_mmio_set_contex_info_addr(struct iosm_mmio *ipc_mmio, phys_addr_t addr)
+{
+ if (!ipc_mmio)
+ return;
+
+ /* store context_info address. This will be stored in the mmio area
+ * during IPC_MEM_DEVICE_IPC_INIT state via ipc_mmio_config()
+ */
+ ipc_mmio->context_info_addr = addr;
+}
+
+int ipc_mmio_get_cp_version(struct iosm_mmio *ipc_mmio)
+{
+ return ipc_mmio ? readl(ipc_mmio->base + ipc_mmio->offset.cp_version) :
+ -EFAULT;
+}
diff --git a/drivers/net/wwan/iosm/iosm_ipc_mmio.h b/drivers/net/wwan/iosm/iosm_ipc_mmio.h
new file mode 100644
index 000000000000..bcf77aea06e7
--- /dev/null
+++ b/drivers/net/wwan/iosm/iosm_ipc_mmio.h
@@ -0,0 +1,193 @@
+/* SPDX-License-Identifier: GPL-2.0-only
+ *
+ * Copyright (C) 2020-21 Intel Corporation.
+ */
+
+#ifndef IOSM_IPC_MMIO_H
+#define IOSM_IPC_MMIO_H
+
+/* Minimal IOSM CP VERSION which has valid CP_CAPABILITIES field */
+#define IOSM_CP_VERSION 0x0100UL
+
+/* DL dir Aggregation support mask */
+#define DL_AGGR BIT(23)
+
+/* UL dir Aggregation support mask */
+#define UL_AGGR BIT(22)
+
+/* UL flow credit support mask */
+#define UL_FLOW_CREDIT BIT(21)
+
+/* Possible states of the IPC finite state machine. */
+enum ipc_mem_device_ipc_state {
+ IPC_MEM_DEVICE_IPC_UNINIT,
+ IPC_MEM_DEVICE_IPC_INIT,
+ IPC_MEM_DEVICE_IPC_RUNNING,
+ IPC_MEM_DEVICE_IPC_RECOVERY,
+ IPC_MEM_DEVICE_IPC_ERROR,
+ IPC_MEM_DEVICE_IPC_DONT_CARE,
+ IPC_MEM_DEVICE_IPC_INVALID = -1
+};
+
+/* Boot ROM exit status. */
+enum rom_exit_code {
+ IMEM_ROM_EXIT_OPEN_EXT = 0x01,
+ IMEM_ROM_EXIT_OPEN_MEM = 0x02,
+ IMEM_ROM_EXIT_CERT_EXT = 0x10,
+ IMEM_ROM_EXIT_CERT_MEM = 0x20,
+ IMEM_ROM_EXIT_FAIL = 0xFF
+};
+
+/* Boot stages */
+enum ipc_mem_exec_stage {
+ IPC_MEM_EXEC_STAGE_RUN = 0x600DF00D,
+ IPC_MEM_EXEC_STAGE_CRASH = 0x8BADF00D,
+ IPC_MEM_EXEC_STAGE_CD_READY = 0xBADC0DED,
+ IPC_MEM_EXEC_STAGE_BOOT = 0xFEEDB007,
+ IPC_MEM_EXEC_STAGE_PSI = 0xFEEDBEEF,
+ IPC_MEM_EXEC_STAGE_EBL = 0xFEEDCAFE,
+ IPC_MEM_EXEC_STAGE_INVALID = 0xFFFFFFFF
+};
+
+/* mmio scratchpad info */
+struct mmio_offset {
+ int exec_stage;
+ int chip_info;
+ int rom_exit_code;
+ int psi_address;
+ int psi_size;
+ int ipc_status;
+ int context_info;
+ int ap_win_base;
+ int ap_win_end;
+ int cp_version;
+ int cp_capability;
+};
+
+/**
+ * struct iosm_mmio - MMIO region mapped to the doorbell scratchpad.
+ * @base: Base address of MMIO region
+ * @dev: Pointer to device structure
+ * @offset: Start offset
+ * @context_info_addr: Physical base address of context info structure
+ * @chip_info_version: Version of chip info structure
+ * @chip_info_size: Size of chip info structure
+ * @has_mux_lite: It doesn't support mux aggergation
+ * @has_ul_flow_credit: Ul flow credit support
+ * @has_slp_no_prot: Device sleep no protocol support
+ * @has_mcr_support: Usage of mcr support
+ */
+struct iosm_mmio {
+ unsigned char __iomem *base;
+ struct device *dev;
+ struct mmio_offset offset;
+ phys_addr_t context_info_addr;
+ unsigned int chip_info_version;
+ unsigned int chip_info_size;
+ u8 has_mux_lite:1,
+ has_ul_flow_credit:1,
+ has_slp_no_prot:1,
+ has_mcr_support:1;
+};
+
+/**
+ * ipc_mmio_init - Allocate mmio instance data
+ * @mmio_addr: Mapped AP base address of the MMIO area.
+ * @dev: Pointer to device structure
+ *
+ * Returns: address of mmio instance data or NULL if fails.
+ */
+struct iosm_mmio *ipc_mmio_init(void __iomem *mmio_addr, struct device *dev);
+
+/**
+ * ipc_mmio_set_psi_addr_and_size - Set start address and size of the
+ * primary system image (PSI) for the
+ * FW dowload.
+ * @ipc_mmio: Pointer to mmio instance
+ * @addr: PSI address
+ * @size: PSI immage size
+ */
+void ipc_mmio_set_psi_addr_and_size(struct iosm_mmio *ipc_mmio, dma_addr_t addr,
+ u32 size);
+
+/**
+ * ipc_mmio_set_contex_info_addr - Stores the Context Info Address in
+ * MMIO instance to share it with CP during
+ * mmio_init.
+ * @ipc_mmio: Pointer to mmio instance
+ * @addr: 64-bit address of AP context information.
+ */
+void ipc_mmio_set_contex_info_addr(struct iosm_mmio *ipc_mmio,
+ phys_addr_t addr);
+
+/**
+ * ipc_mmio_get_cp_version - Write context info and AP memory range addresses.
+ * This needs to be called when CP is in
+ * IPC_MEM_DEVICE_IPC_INIT state
+ * @ipc_mmio: Pointer to mmio instance
+ *
+ * Returns: cp version else failure value on error
+ */
+int ipc_mmio_get_cp_version(struct iosm_mmio *ipc_mmio);
+
+/**
+ * ipc_mmio_get_cp_version - Get the CP IPC version
+ * @ipc_mmio: Pointer to mmio instance
+ *
+ * Returns: version number on success and failure value on error.
+ */
+int ipc_mmio_get_cp_version(struct iosm_mmio *ipc_mmio);
+
+/**
+ * ipc_mmio_get_rom_exit_code - Get exit code from CP boot rom download app
+ * @ipc_mmio: Pointer to mmio instance
+ *
+ * Returns: exit code from CP boot rom download APP
+ */
+enum rom_exit_code ipc_mmio_get_rom_exit_code(struct iosm_mmio *ipc_mmio);
+
+/**
+ * ipc_mmio_get_exec_stage - Query CP execution stage
+ * @ipc_mmio: Pointer to mmio instance
+ *
+ * Returns: CP execution stage
+ */
+enum ipc_mem_exec_stage ipc_mmio_get_exec_stage(struct iosm_mmio *ipc_mmio);
+
+/**
+ * ipc_mmio_get_ipc_state - Query CP IPC state
+ * @ipc_mmio: Pointer to mmio instance
+ *
+ * Returns: CP IPC state
+ */
+enum ipc_mem_device_ipc_state
+ipc_mmio_get_ipc_state(struct iosm_mmio *ipc_mmio);
+
+/**
+ * ipc_mmio_copy_chip_info - Copy size bytes of CP chip info structure
+ * into caller provided buffer
+ * @ipc_mmio: Pointer to mmio instance
+ * @dest: Pointer to caller provided buff
+ * @size: Number of bytes to copy
+ */
+void ipc_mmio_copy_chip_info(struct iosm_mmio *ipc_mmio, void *dest,
+ size_t size);
+
+/**
+ * ipc_mmio_config - Write context info and AP memory range addresses.
+ * This needs to be called when CP is in
+ * IPC_MEM_DEVICE_IPC_INIT state
+ *
+ * @ipc_mmio: Pointer to mmio instance
+ */
+void ipc_mmio_config(struct iosm_mmio *ipc_mmio);
+
+/**
+ * ipc_mmio_update_cp_capability - Read and update modem capability, from mmio
+ * capability offset
+ *
+ * @ipc_mmio: Pointer to mmio instance
+ */
+void ipc_mmio_update_cp_capability(struct iosm_mmio *ipc_mmio);
+
+#endif
--
2.25.1