linux/drivers/spi/spi-dw.h
Damien Le Moal a51acc2400
spi: dw: Add support for 32-bits max xfer size
The Synopsis DesignWare DW_apb_ssi specifications version 3.23 onward
define a 32-bits maximum transfer size synthesis parameter
(SSI_MAX_XFER_SIZE=32) in addition to the legacy 16-bits configuration
(SSI_MAX_XFER_SIZE=16) for SPI controllers. When SSI_MAX_XFER_SIZE=32,
the layout of the ctrlr0 register changes, moving the data frame format
field from bits [3..0] to bits [16..20], and the RX/TX FIFO word size
can be up to 32-bits.

To support this new format, introduce the DW SPI capability flag
DW_SPI_CAP_DFS32 to indicate that a controller is configured with
SSI_MAX_XFER_SIZE=32. Since SSI_MAX_XFER_SIZE is a controller synthesis
parameter not accessible through a register, the detection of this
parameter value is done in spi_hw_init() by writing and reading the
ctrlr0 register and testing the value of bits [3..0]. These bits are
ignored (unchanged) for SSI_MAX_XFER_SIZE=16, allowing the detection.
If a DFS32 capable SPI controller is detected, the new field dfs_offset
in struct dw_spi is set to SPI_DFS32_OFFSET (16).

dw_spi_update_config() is modified to set the data frame size field at
the correct position is the CTRLR0 register, as indicated by the
dfs_offset field of the dw_spi structure.

The DW_SPI_CAP_DFS32 flag is also unconditionally set for SPI slave
controllers, e.g. controllers that have the DW_SPI_CAP_DWC_SSI
capability flag set. However, for these ssi controllers, the dfs_offset
field is set to 0 as before (as per specifications).

Finally, for any controller with the DW_SPI_CAP_DFS32 capability flag
set, dw_spi_add_host() extends the value of bits_per_word_mask from
16-bits to 32-bits. dw_reader() and dw_writer() are also modified to
handle 32-bits iTX/RX FIFO words.

Suggested-by: Sean Anderson <seanga2@gmail.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Acked-by: Serge Semin <fancer.lancer@gmail.com>
Link: https://lore.kernel.org/r/20201206011817.11700-3-damien.lemoal@wdc.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-12-09 12:14:22 +00:00

303 lines
7.7 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef DW_SPI_HEADER_H
#define DW_SPI_HEADER_H
#include <linux/bits.h>
#include <linux/completion.h>
#include <linux/debugfs.h>
#include <linux/irqreturn.h>
#include <linux/io.h>
#include <linux/scatterlist.h>
#include <linux/spi/spi-mem.h>
#include <linux/bitfield.h>
/* Register offsets */
#define DW_SPI_CTRLR0 0x00
#define DW_SPI_CTRLR1 0x04
#define DW_SPI_SSIENR 0x08
#define DW_SPI_MWCR 0x0c
#define DW_SPI_SER 0x10
#define DW_SPI_BAUDR 0x14
#define DW_SPI_TXFTLR 0x18
#define DW_SPI_RXFTLR 0x1c
#define DW_SPI_TXFLR 0x20
#define DW_SPI_RXFLR 0x24
#define DW_SPI_SR 0x28
#define DW_SPI_IMR 0x2c
#define DW_SPI_ISR 0x30
#define DW_SPI_RISR 0x34
#define DW_SPI_TXOICR 0x38
#define DW_SPI_RXOICR 0x3c
#define DW_SPI_RXUICR 0x40
#define DW_SPI_MSTICR 0x44
#define DW_SPI_ICR 0x48
#define DW_SPI_DMACR 0x4c
#define DW_SPI_DMATDLR 0x50
#define DW_SPI_DMARDLR 0x54
#define DW_SPI_IDR 0x58
#define DW_SPI_VERSION 0x5c
#define DW_SPI_DR 0x60
#define DW_SPI_RX_SAMPLE_DLY 0xf0
#define DW_SPI_CS_OVERRIDE 0xf4
/* Bit fields in CTRLR0 */
#define SPI_DFS_OFFSET 0
#define SPI_DFS_MASK GENMASK(3, 0)
#define SPI_DFS32_OFFSET 16
#define SPI_FRF_OFFSET 4
#define SPI_FRF_SPI 0x0
#define SPI_FRF_SSP 0x1
#define SPI_FRF_MICROWIRE 0x2
#define SPI_FRF_RESV 0x3
#define SPI_MODE_OFFSET 6
#define SPI_SCPH_OFFSET 6
#define SPI_SCOL_OFFSET 7
#define SPI_TMOD_OFFSET 8
#define SPI_TMOD_MASK (0x3 << SPI_TMOD_OFFSET)
#define SPI_TMOD_TR 0x0 /* xmit & recv */
#define SPI_TMOD_TO 0x1 /* xmit only */
#define SPI_TMOD_RO 0x2 /* recv only */
#define SPI_TMOD_EPROMREAD 0x3 /* eeprom read mode */
#define SPI_SLVOE_OFFSET 10
#define SPI_SRL_OFFSET 11
#define SPI_CFS_OFFSET 12
/* Bit fields in CTRLR0 based on DWC_ssi_databook.pdf v1.01a */
#define DWC_SSI_CTRLR0_SRL_OFFSET 13
#define DWC_SSI_CTRLR0_TMOD_OFFSET 10
#define DWC_SSI_CTRLR0_TMOD_MASK GENMASK(11, 10)
#define DWC_SSI_CTRLR0_SCPOL_OFFSET 9
#define DWC_SSI_CTRLR0_SCPH_OFFSET 8
#define DWC_SSI_CTRLR0_FRF_OFFSET 6
#define DWC_SSI_CTRLR0_DFS_OFFSET 0
/*
* For Keem Bay, CTRLR0[31] is used to select controller mode.
* 0: SSI is slave
* 1: SSI is master
*/
#define DWC_SSI_CTRLR0_KEEMBAY_MST BIT(31)
/* Bit fields in CTRLR1 */
#define SPI_NDF_MASK GENMASK(15, 0)
/* Bit fields in SR, 7 bits */
#define SR_MASK 0x7f /* cover 7 bits */
#define SR_BUSY (1 << 0)
#define SR_TF_NOT_FULL (1 << 1)
#define SR_TF_EMPT (1 << 2)
#define SR_RF_NOT_EMPT (1 << 3)
#define SR_RF_FULL (1 << 4)
#define SR_TX_ERR (1 << 5)
#define SR_DCOL (1 << 6)
/* Bit fields in ISR, IMR, RISR, 7 bits */
#define SPI_INT_TXEI (1 << 0)
#define SPI_INT_TXOI (1 << 1)
#define SPI_INT_RXUI (1 << 2)
#define SPI_INT_RXOI (1 << 3)
#define SPI_INT_RXFI (1 << 4)
#define SPI_INT_MSTI (1 << 5)
/* Bit fields in DMACR */
#define SPI_DMA_RDMAE (1 << 0)
#define SPI_DMA_TDMAE (1 << 1)
#define SPI_WAIT_RETRIES 5
#define SPI_BUF_SIZE \
(sizeof_field(struct spi_mem_op, cmd.opcode) + \
sizeof_field(struct spi_mem_op, addr.val) + 256)
#define SPI_GET_BYTE(_val, _idx) \
((_val) >> (BITS_PER_BYTE * (_idx)) & 0xff)
enum dw_ssi_type {
SSI_MOTO_SPI = 0,
SSI_TI_SSP,
SSI_NS_MICROWIRE,
};
/* DW SPI capabilities */
#define DW_SPI_CAP_CS_OVERRIDE BIT(0)
#define DW_SPI_CAP_KEEMBAY_MST BIT(1)
#define DW_SPI_CAP_DWC_SSI BIT(2)
#define DW_SPI_CAP_DFS32 BIT(3)
/* Slave spi_transfer/spi_mem_op related */
struct dw_spi_cfg {
u8 tmode;
u8 dfs;
u32 ndf;
u32 freq;
};
struct dw_spi;
struct dw_spi_dma_ops {
int (*dma_init)(struct device *dev, struct dw_spi *dws);
void (*dma_exit)(struct dw_spi *dws);
int (*dma_setup)(struct dw_spi *dws, struct spi_transfer *xfer);
bool (*can_dma)(struct spi_controller *master, struct spi_device *spi,
struct spi_transfer *xfer);
int (*dma_transfer)(struct dw_spi *dws, struct spi_transfer *xfer);
void (*dma_stop)(struct dw_spi *dws);
};
struct dw_spi {
struct spi_controller *master;
void __iomem *regs;
unsigned long paddr;
int irq;
u32 fifo_len; /* depth of the FIFO buffer */
unsigned int dfs_offset; /* CTRLR0 DFS field offset */
u32 max_mem_freq; /* max mem-ops bus freq */
u32 max_freq; /* max bus freq supported */
u32 caps; /* DW SPI capabilities */
u32 reg_io_width; /* DR I/O width in bytes */
u16 bus_num;
u16 num_cs; /* supported slave numbers */
void (*set_cs)(struct spi_device *spi, bool enable);
/* Current message transfer state info */
void *tx;
unsigned int tx_len;
void *rx;
unsigned int rx_len;
u8 buf[SPI_BUF_SIZE];
int dma_mapped;
u8 n_bytes; /* current is a 1/2 bytes op */
irqreturn_t (*transfer_handler)(struct dw_spi *dws);
u32 current_freq; /* frequency in hz */
u32 cur_rx_sample_dly;
u32 def_rx_sample_dly_ns;
/* Custom memory operations */
struct spi_controller_mem_ops mem_ops;
/* DMA info */
struct dma_chan *txchan;
u32 txburst;
struct dma_chan *rxchan;
u32 rxburst;
u32 dma_sg_burst;
unsigned long dma_chan_busy;
dma_addr_t dma_addr; /* phy address of the Data register */
const struct dw_spi_dma_ops *dma_ops;
struct completion dma_completion;
#ifdef CONFIG_DEBUG_FS
struct dentry *debugfs;
struct debugfs_regset32 regset;
#endif
};
static inline u32 dw_readl(struct dw_spi *dws, u32 offset)
{
return __raw_readl(dws->regs + offset);
}
static inline void dw_writel(struct dw_spi *dws, u32 offset, u32 val)
{
__raw_writel(val, dws->regs + offset);
}
static inline u32 dw_read_io_reg(struct dw_spi *dws, u32 offset)
{
switch (dws->reg_io_width) {
case 2:
return readw_relaxed(dws->regs + offset);
case 4:
default:
return readl_relaxed(dws->regs + offset);
}
}
static inline void dw_write_io_reg(struct dw_spi *dws, u32 offset, u32 val)
{
switch (dws->reg_io_width) {
case 2:
writew_relaxed(val, dws->regs + offset);
break;
case 4:
default:
writel_relaxed(val, dws->regs + offset);
break;
}
}
static inline void spi_enable_chip(struct dw_spi *dws, int enable)
{
dw_writel(dws, DW_SPI_SSIENR, (enable ? 1 : 0));
}
static inline void spi_set_clk(struct dw_spi *dws, u16 div)
{
dw_writel(dws, DW_SPI_BAUDR, div);
}
/* Disable IRQ bits */
static inline void spi_mask_intr(struct dw_spi *dws, u32 mask)
{
u32 new_mask;
new_mask = dw_readl(dws, DW_SPI_IMR) & ~mask;
dw_writel(dws, DW_SPI_IMR, new_mask);
}
/* Enable IRQ bits */
static inline void spi_umask_intr(struct dw_spi *dws, u32 mask)
{
u32 new_mask;
new_mask = dw_readl(dws, DW_SPI_IMR) | mask;
dw_writel(dws, DW_SPI_IMR, new_mask);
}
/*
* This disables the SPI controller, interrupts, clears the interrupts status
* and CS, then re-enables the controller back. Transmit and receive FIFO
* buffers are cleared when the device is disabled.
*/
static inline void spi_reset_chip(struct dw_spi *dws)
{
spi_enable_chip(dws, 0);
spi_mask_intr(dws, 0xff);
dw_readl(dws, DW_SPI_ICR);
dw_writel(dws, DW_SPI_SER, 0);
spi_enable_chip(dws, 1);
}
static inline void spi_shutdown_chip(struct dw_spi *dws)
{
spi_enable_chip(dws, 0);
spi_set_clk(dws, 0);
}
extern void dw_spi_set_cs(struct spi_device *spi, bool enable);
extern void dw_spi_update_config(struct dw_spi *dws, struct spi_device *spi,
struct dw_spi_cfg *cfg);
extern int dw_spi_check_status(struct dw_spi *dws, bool raw);
extern int dw_spi_add_host(struct device *dev, struct dw_spi *dws);
extern void dw_spi_remove_host(struct dw_spi *dws);
extern int dw_spi_suspend_host(struct dw_spi *dws);
extern int dw_spi_resume_host(struct dw_spi *dws);
#ifdef CONFIG_SPI_DW_DMA
extern void dw_spi_dma_setup_mfld(struct dw_spi *dws);
extern void dw_spi_dma_setup_generic(struct dw_spi *dws);
#else
static inline void dw_spi_dma_setup_mfld(struct dw_spi *dws) {}
static inline void dw_spi_dma_setup_generic(struct dw_spi *dws) {}
#endif /* !CONFIG_SPI_DW_DMA */
#endif /* DW_SPI_HEADER_H */