diff options
Diffstat (limited to 'drivers/hid/intel-thc-hid/intel-thc/intel-thc-dma.h')
| -rw-r--r-- | drivers/hid/intel-thc-hid/intel-thc/intel-thc-dma.h | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/drivers/hid/intel-thc-hid/intel-thc/intel-thc-dma.h b/drivers/hid/intel-thc-hid/intel-thc/intel-thc-dma.h new file mode 100644 index 000000000000..78917400492c --- /dev/null +++ b/drivers/hid/intel-thc-hid/intel-thc/intel-thc-dma.h @@ -0,0 +1,154 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright (c) 2024 Intel Corporation */ + +#ifndef _INTEL_THC_DMA_H_ +#define _INTEL_THC_DMA_H_ + +#include <linux/bits.h> +#include <linux/dma-mapping.h> +#include <linux/sizes.h> +#include <linux/time64.h> +#include <linux/types.h> + +#define THC_POINTER_MASK GENMASK(6, 0) +#define THC_POINTER_WRAPAROUND 0x80 +#define THC_WRAPAROUND_VALUE_ODD 0x10 +#define THC_WRAPAROUND_VALUE_EVEN 0x90 +#define THC_MIN_BYTES_PER_SG_LIST_ENTRY SZ_4K + +#define THC_DEFAULT_RXDMA_POLLING_US_INTERVAL 100 +#define THC_DEFAULT_RXDMA_POLLING_US_TIMEOUT (10 * USEC_PER_MSEC) + +/* + * THC needs 1KB aligned address, dest_addr is 54 bits, not 64, + * so don't need to send the lower 10-bits of address. + */ +#define THC_ADDRESS_SHIFT 10 + +/** + * THC DMA channels: + * @THC_RXDMA1: Legacy channel, reserved for raw data reading + * @THC_RXDMA2: DMA to read HID data from touch device + * @THC_TXDMA: DMA to write to touch device + * @THC_SWDMA: SW triggered DMA to write and read from touch device + */ +enum thc_dma_channel { + THC_RXDMA1 = 0, + THC_RXDMA2 = 1, + THC_TXDMA = 2, + THC_SWDMA = 3, + MAX_THC_DMA_CHANNEL +}; + +/** + * THC DMA Physical Memory Descriptor (PRD) + * @dest_addr: Bit[53:0], destination address in system memory + * @int_on_completion: Bit[63], if set, thc will trigger interrupt to driver + * @len: Bit[87:64], length of this entry + * @end_of_prd: Bit[88], if set, this entry is last one of current PRD table + * @hw_status: Bit[90:89], hardware status bits + */ +struct thc_prd_entry { + u64 dest_addr : 54; + u64 reserved1 : 9; + u64 int_on_completion : 1; + u64 len : 24; + u64 end_of_prd : 1; + u64 hw_status : 2; + u64 reserved2 : 37; +}; + +/* + * Max OS memory fragmentation will be at a 4KB boundary, thus to address 1MB + * of virtually contiguous memory 256 PRD entries are required for a single + * PRD Table. SW writes the number of PRD Entries for each PRD table in the + * THC_M_PRT_RPRD_CNTRL.PTEC register field. The PRD entry's length must be + * multiple of 4KB except for the last entry in a PRD table. + * This is the max possible number of etries supported by HW, in practise we + * there will be less entries in each prd table(the actual number will be + * given by scatter-gather list allocation). + */ +#define PRD_ENTRIES_NUM 16 + +/* + * Number of PRD tables equals to number of data buffers. + * The max number of PRD tables supported by the HW is 128, + * but we allocate only 16. + */ +#define PRD_TABLES_NUM 16 + +/* THC DMA Physical Memory Descriptor Table */ +struct thc_prd_table { + struct thc_prd_entry entries[PRD_ENTRIES_NUM]; +}; + +#define PRD_TABLE_SIZE sizeof(struct thc_prd_table) + +/** + * struct thc_dma_configuration - THC DMA configure + * @dma_channel: DMA channel for current DMA configuration + * @prd_tbls_dma_handle: DMA buffer handle + * @dir: Direction of DMA for this config + * @prd_tbls: PRD tables for current DMA + * @sgls: Array of pointers to scatter-gather lists + * @sgls_nent: Actual number of entries per scatter-gather list + * @prd_tbl_num: Actual number of PRD tables + * @max_packet_size: Size of the buffer needed for 1 DMA message (1 PRD table) + * @prd_base_addr_high: High 32bits memory address where stores PRD table + * @prd_base_addr_low: Low 32bits memory address where stores PRD table + * @prd_cntrl: PRD control register value + * @dma_cntrl: DMA control register value + */ +struct thc_dma_configuration { + enum thc_dma_channel dma_channel; + dma_addr_t prd_tbls_dma_handle; + enum dma_data_direction dir; + bool is_enabled; + + struct thc_prd_table *prd_tbls; + struct scatterlist *sgls[PRD_TABLES_NUM]; + u8 sgls_nent[PRD_TABLES_NUM]; + u8 prd_tbl_num; + + size_t max_packet_size; + u32 prd_base_addr_high; + u32 prd_base_addr_low; + u32 prd_cntrl; + u32 dma_cntrl; +}; + +/** + * struct thc_dma_context - THC DMA context + * @thc_dma_configuration: Array of all THC Channel configures + * @use_write_interrupts: Indicate TxDMA using interrupt or polling + * @rx_max_size_en: Temp flag to indicate THC I2C Rx max input size control feature + * enabled or not, only be used during SWDMA operation. + * @rx_int_delay_en: Temp flag to indicate THC I2C Rx interrupt delay feature + * enabled or not, only be used during SWDMA operation. + */ +struct thc_dma_context { + struct thc_dma_configuration dma_config[MAX_THC_DMA_CHANNEL]; + u8 use_write_interrupts; + + bool rx_max_size_en; + bool rx_int_delay_en; +}; + +struct thc_device; + +int thc_dma_set_max_packet_sizes(struct thc_device *dev, + size_t mps_read1, size_t mps_read2, + size_t mps_write, size_t mps_swdma); +int thc_dma_allocate(struct thc_device *dev); +int thc_dma_configure(struct thc_device *dev); +void thc_dma_unconfigure(struct thc_device *dev); +void thc_dma_release(struct thc_device *dev); +int thc_rxdma_read(struct thc_device *dev, enum thc_dma_channel dma_channel, + void *read_buff, size_t *read_len, int *read_finished); +int thc_swdma_read(struct thc_device *dev, void *write_buff, size_t write_len, + u32 *prd_tbl_len, void *read_buff, size_t *read_len); +int thc_dma_write(struct thc_device *dev, void *buffer, size_t buf_len); + +struct thc_dma_context *thc_dma_init(struct thc_device *dev); + +#endif /* _INTEL_THC_DMA_H_ */ |