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![Christoph Hellwig](/assets/img/avatar_default.png)
The DMA API does its own zone decisions based on the coherent_dma_mask. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Mark Brown <broonie@kernel.org>
726 lines
19 KiB
C
726 lines
19 KiB
C
/*
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* PIC32 Quad SPI controller driver.
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*
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* Purna Chandra Mandal <purna.mandal@microchip.com>
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* Copyright (c) 2016, Microchip Technology Inc.
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*
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* This program is free software; you can distribute it and/or modify it
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* under the terms of the GNU General Public License (Version 2) as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* for more details.
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*/
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#include <linux/clk.h>
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#include <linux/dma-mapping.h>
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#include <linux/interrupt.h>
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#include <linux/io.h>
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#include <linux/iopoll.h>
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#include <linux/module.h>
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#include <linux/of.h>
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#include <linux/platform_device.h>
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#include <linux/slab.h>
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#include <linux/spi/spi.h>
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/* SQI registers */
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#define PESQI_XIP_CONF1_REG 0x00
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#define PESQI_XIP_CONF2_REG 0x04
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#define PESQI_CONF_REG 0x08
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#define PESQI_CTRL_REG 0x0C
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#define PESQI_CLK_CTRL_REG 0x10
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#define PESQI_CMD_THRES_REG 0x14
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#define PESQI_INT_THRES_REG 0x18
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#define PESQI_INT_ENABLE_REG 0x1C
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#define PESQI_INT_STAT_REG 0x20
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#define PESQI_TX_DATA_REG 0x24
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#define PESQI_RX_DATA_REG 0x28
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#define PESQI_STAT1_REG 0x2C
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#define PESQI_STAT2_REG 0x30
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#define PESQI_BD_CTRL_REG 0x34
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#define PESQI_BD_CUR_ADDR_REG 0x38
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#define PESQI_BD_BASE_ADDR_REG 0x40
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#define PESQI_BD_STAT_REG 0x44
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#define PESQI_BD_POLL_CTRL_REG 0x48
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#define PESQI_BD_TX_DMA_STAT_REG 0x4C
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#define PESQI_BD_RX_DMA_STAT_REG 0x50
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#define PESQI_THRES_REG 0x54
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#define PESQI_INT_SIGEN_REG 0x58
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/* PESQI_CONF_REG fields */
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#define PESQI_MODE 0x7
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#define PESQI_MODE_BOOT 0
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#define PESQI_MODE_PIO 1
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#define PESQI_MODE_DMA 2
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#define PESQI_MODE_XIP 3
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#define PESQI_MODE_SHIFT 0
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#define PESQI_CPHA BIT(3)
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#define PESQI_CPOL BIT(4)
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#define PESQI_LSBF BIT(5)
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#define PESQI_RXLATCH BIT(7)
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#define PESQI_SERMODE BIT(8)
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#define PESQI_WP_EN BIT(9)
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#define PESQI_HOLD_EN BIT(10)
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#define PESQI_BURST_EN BIT(12)
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#define PESQI_CS_CTRL_HW BIT(15)
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#define PESQI_SOFT_RESET BIT(16)
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#define PESQI_LANES_SHIFT 20
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#define PESQI_SINGLE_LANE 0
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#define PESQI_DUAL_LANE 1
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#define PESQI_QUAD_LANE 2
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#define PESQI_CSEN_SHIFT 24
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#define PESQI_EN BIT(23)
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/* PESQI_CLK_CTRL_REG fields */
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#define PESQI_CLK_EN BIT(0)
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#define PESQI_CLK_STABLE BIT(1)
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#define PESQI_CLKDIV_SHIFT 8
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#define PESQI_CLKDIV 0xff
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/* PESQI_INT_THR/CMD_THR_REG */
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#define PESQI_TXTHR_MASK 0x1f
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#define PESQI_TXTHR_SHIFT 8
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#define PESQI_RXTHR_MASK 0x1f
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#define PESQI_RXTHR_SHIFT 0
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/* PESQI_INT_EN/INT_STAT/INT_SIG_EN_REG */
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#define PESQI_TXEMPTY BIT(0)
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#define PESQI_TXFULL BIT(1)
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#define PESQI_TXTHR BIT(2)
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#define PESQI_RXEMPTY BIT(3)
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#define PESQI_RXFULL BIT(4)
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#define PESQI_RXTHR BIT(5)
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#define PESQI_BDDONE BIT(9) /* BD processing complete */
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#define PESQI_PKTCOMP BIT(10) /* packet processing complete */
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#define PESQI_DMAERR BIT(11) /* error */
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/* PESQI_BD_CTRL_REG */
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#define PESQI_DMA_EN BIT(0) /* enable DMA engine */
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#define PESQI_POLL_EN BIT(1) /* enable polling */
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#define PESQI_BDP_START BIT(2) /* start BD processor */
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/* PESQI controller buffer descriptor */
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struct buf_desc {
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u32 bd_ctrl; /* control */
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u32 bd_status; /* reserved */
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u32 bd_addr; /* DMA buffer addr */
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u32 bd_nextp; /* next item in chain */
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};
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/* bd_ctrl */
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#define BD_BUFLEN 0x1ff
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#define BD_CBD_INT_EN BIT(16) /* Current BD is processed */
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#define BD_PKT_INT_EN BIT(17) /* All BDs of PKT processed */
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#define BD_LIFM BIT(18) /* last data of pkt */
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#define BD_LAST BIT(19) /* end of list */
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#define BD_DATA_RECV BIT(20) /* receive data */
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#define BD_DDR BIT(21) /* DDR mode */
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#define BD_DUAL BIT(22) /* Dual SPI */
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#define BD_QUAD BIT(23) /* Quad SPI */
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#define BD_LSBF BIT(25) /* LSB First */
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#define BD_STAT_CHECK BIT(27) /* Status poll */
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#define BD_DEVSEL_SHIFT 28 /* CS */
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#define BD_CS_DEASSERT BIT(30) /* de-assert CS after current BD */
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#define BD_EN BIT(31) /* BD owned by H/W */
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/**
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* struct ring_desc - Representation of SQI ring descriptor
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* @list: list element to add to free or used list.
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* @bd: PESQI controller buffer descriptor
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* @bd_dma: DMA address of PESQI controller buffer descriptor
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* @xfer_len: transfer length
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*/
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struct ring_desc {
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struct list_head list;
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struct buf_desc *bd;
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dma_addr_t bd_dma;
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u32 xfer_len;
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};
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/* Global constants */
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#define PESQI_BD_BUF_LEN_MAX 256
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#define PESQI_BD_COUNT 256 /* max 64KB data per spi message */
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struct pic32_sqi {
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void __iomem *regs;
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struct clk *sys_clk;
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struct clk *base_clk; /* drives spi clock */
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struct spi_master *master;
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int irq;
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struct completion xfer_done;
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struct ring_desc *ring;
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void *bd;
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dma_addr_t bd_dma;
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struct list_head bd_list_free; /* free */
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struct list_head bd_list_used; /* allocated */
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struct spi_device *cur_spi;
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u32 cur_speed;
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u8 cur_mode;
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};
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static inline void pic32_setbits(void __iomem *reg, u32 set)
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{
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writel(readl(reg) | set, reg);
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}
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static inline void pic32_clrbits(void __iomem *reg, u32 clr)
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{
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writel(readl(reg) & ~clr, reg);
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}
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static int pic32_sqi_set_clk_rate(struct pic32_sqi *sqi, u32 sck)
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{
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u32 val, div;
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/* div = base_clk / (2 * spi_clk) */
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div = clk_get_rate(sqi->base_clk) / (2 * sck);
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div &= PESQI_CLKDIV;
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val = readl(sqi->regs + PESQI_CLK_CTRL_REG);
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/* apply new divider */
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val &= ~(PESQI_CLK_STABLE | (PESQI_CLKDIV << PESQI_CLKDIV_SHIFT));
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val |= div << PESQI_CLKDIV_SHIFT;
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writel(val, sqi->regs + PESQI_CLK_CTRL_REG);
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/* wait for stability */
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return readl_poll_timeout(sqi->regs + PESQI_CLK_CTRL_REG, val,
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val & PESQI_CLK_STABLE, 1, 5000);
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}
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static inline void pic32_sqi_enable_int(struct pic32_sqi *sqi)
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{
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u32 mask = PESQI_DMAERR | PESQI_BDDONE | PESQI_PKTCOMP;
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writel(mask, sqi->regs + PESQI_INT_ENABLE_REG);
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/* INT_SIGEN works as interrupt-gate to INTR line */
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writel(mask, sqi->regs + PESQI_INT_SIGEN_REG);
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}
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static inline void pic32_sqi_disable_int(struct pic32_sqi *sqi)
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{
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writel(0, sqi->regs + PESQI_INT_ENABLE_REG);
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writel(0, sqi->regs + PESQI_INT_SIGEN_REG);
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}
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static irqreturn_t pic32_sqi_isr(int irq, void *dev_id)
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{
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struct pic32_sqi *sqi = dev_id;
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u32 enable, status;
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enable = readl(sqi->regs + PESQI_INT_ENABLE_REG);
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status = readl(sqi->regs + PESQI_INT_STAT_REG);
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/* check spurious interrupt */
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if (!status)
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return IRQ_NONE;
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if (status & PESQI_DMAERR) {
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enable = 0;
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goto irq_done;
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}
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if (status & PESQI_TXTHR)
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enable &= ~(PESQI_TXTHR | PESQI_TXFULL | PESQI_TXEMPTY);
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if (status & PESQI_RXTHR)
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enable &= ~(PESQI_RXTHR | PESQI_RXFULL | PESQI_RXEMPTY);
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if (status & PESQI_BDDONE)
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enable &= ~PESQI_BDDONE;
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/* packet processing completed */
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if (status & PESQI_PKTCOMP) {
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/* mask all interrupts */
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enable = 0;
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/* complete trasaction */
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complete(&sqi->xfer_done);
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}
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irq_done:
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/* interrupts are sticky, so mask when handled */
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writel(enable, sqi->regs + PESQI_INT_ENABLE_REG);
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return IRQ_HANDLED;
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}
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static struct ring_desc *ring_desc_get(struct pic32_sqi *sqi)
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{
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struct ring_desc *rdesc;
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if (list_empty(&sqi->bd_list_free))
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return NULL;
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rdesc = list_first_entry(&sqi->bd_list_free, struct ring_desc, list);
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list_move_tail(&rdesc->list, &sqi->bd_list_used);
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return rdesc;
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}
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static void ring_desc_put(struct pic32_sqi *sqi, struct ring_desc *rdesc)
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{
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list_move(&rdesc->list, &sqi->bd_list_free);
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}
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static int pic32_sqi_one_transfer(struct pic32_sqi *sqi,
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struct spi_message *mesg,
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struct spi_transfer *xfer)
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{
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struct spi_device *spi = mesg->spi;
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struct scatterlist *sg, *sgl;
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struct ring_desc *rdesc;
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struct buf_desc *bd;
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int nents, i;
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u32 bd_ctrl;
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u32 nbits;
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/* Device selection */
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bd_ctrl = spi->chip_select << BD_DEVSEL_SHIFT;
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/* half-duplex: select transfer buffer, direction and lane */
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if (xfer->rx_buf) {
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bd_ctrl |= BD_DATA_RECV;
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nbits = xfer->rx_nbits;
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sgl = xfer->rx_sg.sgl;
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nents = xfer->rx_sg.nents;
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} else {
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nbits = xfer->tx_nbits;
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sgl = xfer->tx_sg.sgl;
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nents = xfer->tx_sg.nents;
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}
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if (nbits & SPI_NBITS_QUAD)
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bd_ctrl |= BD_QUAD;
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else if (nbits & SPI_NBITS_DUAL)
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bd_ctrl |= BD_DUAL;
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/* LSB first */
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if (spi->mode & SPI_LSB_FIRST)
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bd_ctrl |= BD_LSBF;
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/* ownership to hardware */
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bd_ctrl |= BD_EN;
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for_each_sg(sgl, sg, nents, i) {
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/* get ring descriptor */
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rdesc = ring_desc_get(sqi);
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if (!rdesc)
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break;
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bd = rdesc->bd;
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/* BD CTRL: length */
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rdesc->xfer_len = sg_dma_len(sg);
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bd->bd_ctrl = bd_ctrl;
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bd->bd_ctrl |= rdesc->xfer_len;
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/* BD STAT */
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bd->bd_status = 0;
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/* BD BUFFER ADDRESS */
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bd->bd_addr = sg->dma_address;
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}
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return 0;
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}
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static int pic32_sqi_prepare_hardware(struct spi_master *master)
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{
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struct pic32_sqi *sqi = spi_master_get_devdata(master);
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/* enable spi interface */
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pic32_setbits(sqi->regs + PESQI_CONF_REG, PESQI_EN);
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/* enable spi clk */
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pic32_setbits(sqi->regs + PESQI_CLK_CTRL_REG, PESQI_CLK_EN);
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return 0;
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}
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static bool pic32_sqi_can_dma(struct spi_master *master,
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struct spi_device *spi,
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struct spi_transfer *x)
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{
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/* Do DMA irrespective of transfer size */
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return true;
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}
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static int pic32_sqi_one_message(struct spi_master *master,
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struct spi_message *msg)
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{
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struct spi_device *spi = msg->spi;
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struct ring_desc *rdesc, *next;
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struct spi_transfer *xfer;
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struct pic32_sqi *sqi;
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int ret = 0, mode;
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unsigned long timeout;
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u32 val;
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sqi = spi_master_get_devdata(master);
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reinit_completion(&sqi->xfer_done);
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msg->actual_length = 0;
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/* We can't handle spi_transfer specific "speed_hz", "bits_per_word"
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* and "delay_usecs". But spi_device specific speed and mode change
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* can be handled at best during spi chip-select switch.
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*/
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if (sqi->cur_spi != spi) {
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/* set spi speed */
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if (sqi->cur_speed != spi->max_speed_hz) {
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sqi->cur_speed = spi->max_speed_hz;
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ret = pic32_sqi_set_clk_rate(sqi, spi->max_speed_hz);
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if (ret)
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dev_warn(&spi->dev, "set_clk, %d\n", ret);
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}
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/* set spi mode */
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mode = spi->mode & (SPI_MODE_3 | SPI_LSB_FIRST);
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if (sqi->cur_mode != mode) {
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val = readl(sqi->regs + PESQI_CONF_REG);
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val &= ~(PESQI_CPOL | PESQI_CPHA | PESQI_LSBF);
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if (mode & SPI_CPOL)
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val |= PESQI_CPOL;
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if (mode & SPI_LSB_FIRST)
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val |= PESQI_LSBF;
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val |= PESQI_CPHA;
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writel(val, sqi->regs + PESQI_CONF_REG);
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sqi->cur_mode = mode;
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}
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sqi->cur_spi = spi;
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}
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/* prepare hardware desc-list(BD) for transfer(s) */
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list_for_each_entry(xfer, &msg->transfers, transfer_list) {
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ret = pic32_sqi_one_transfer(sqi, msg, xfer);
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if (ret) {
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dev_err(&spi->dev, "xfer %p err\n", xfer);
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goto xfer_out;
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}
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}
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/* BDs are prepared and chained. Now mark LAST_BD, CS_DEASSERT at last
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* element of the list.
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*/
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rdesc = list_last_entry(&sqi->bd_list_used, struct ring_desc, list);
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rdesc->bd->bd_ctrl |= BD_LAST | BD_CS_DEASSERT |
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BD_LIFM | BD_PKT_INT_EN;
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/* set base address BD list for DMA engine */
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rdesc = list_first_entry(&sqi->bd_list_used, struct ring_desc, list);
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writel(rdesc->bd_dma, sqi->regs + PESQI_BD_BASE_ADDR_REG);
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/* enable interrupt */
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pic32_sqi_enable_int(sqi);
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/* enable DMA engine */
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val = PESQI_DMA_EN | PESQI_POLL_EN | PESQI_BDP_START;
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writel(val, sqi->regs + PESQI_BD_CTRL_REG);
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/* wait for xfer completion */
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timeout = wait_for_completion_timeout(&sqi->xfer_done, 5 * HZ);
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if (timeout == 0) {
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dev_err(&sqi->master->dev, "wait timedout/interrupted\n");
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ret = -ETIMEDOUT;
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msg->status = ret;
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} else {
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/* success */
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msg->status = 0;
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ret = 0;
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}
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/* disable DMA */
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writel(0, sqi->regs + PESQI_BD_CTRL_REG);
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pic32_sqi_disable_int(sqi);
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xfer_out:
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list_for_each_entry_safe_reverse(rdesc, next,
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&sqi->bd_list_used, list) {
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/* Update total byte transferred */
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msg->actual_length += rdesc->xfer_len;
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/* release ring descr */
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ring_desc_put(sqi, rdesc);
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}
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spi_finalize_current_message(spi->master);
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return ret;
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}
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static int pic32_sqi_unprepare_hardware(struct spi_master *master)
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{
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struct pic32_sqi *sqi = spi_master_get_devdata(master);
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/* disable clk */
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pic32_clrbits(sqi->regs + PESQI_CLK_CTRL_REG, PESQI_CLK_EN);
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/* disable spi */
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pic32_clrbits(sqi->regs + PESQI_CONF_REG, PESQI_EN);
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return 0;
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}
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static int ring_desc_ring_alloc(struct pic32_sqi *sqi)
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{
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struct ring_desc *rdesc;
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struct buf_desc *bd;
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int i;
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/* allocate coherent DMAable memory for hardware buffer descriptors. */
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sqi->bd = dma_zalloc_coherent(&sqi->master->dev,
|
|
sizeof(*bd) * PESQI_BD_COUNT,
|
|
&sqi->bd_dma, GFP_KERNEL);
|
|
if (!sqi->bd) {
|
|
dev_err(&sqi->master->dev, "failed allocating dma buffer\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/* allocate software ring descriptors */
|
|
sqi->ring = kcalloc(PESQI_BD_COUNT, sizeof(*rdesc), GFP_KERNEL);
|
|
if (!sqi->ring) {
|
|
dma_free_coherent(&sqi->master->dev,
|
|
sizeof(*bd) * PESQI_BD_COUNT,
|
|
sqi->bd, sqi->bd_dma);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
bd = (struct buf_desc *)sqi->bd;
|
|
|
|
INIT_LIST_HEAD(&sqi->bd_list_free);
|
|
INIT_LIST_HEAD(&sqi->bd_list_used);
|
|
|
|
/* initialize ring-desc */
|
|
for (i = 0, rdesc = sqi->ring; i < PESQI_BD_COUNT; i++, rdesc++) {
|
|
INIT_LIST_HEAD(&rdesc->list);
|
|
rdesc->bd = &bd[i];
|
|
rdesc->bd_dma = sqi->bd_dma + (void *)&bd[i] - (void *)bd;
|
|
list_add_tail(&rdesc->list, &sqi->bd_list_free);
|
|
}
|
|
|
|
/* Prepare BD: chain to next BD(s) */
|
|
for (i = 0, rdesc = sqi->ring; i < PESQI_BD_COUNT - 1; i++)
|
|
bd[i].bd_nextp = rdesc[i + 1].bd_dma;
|
|
bd[PESQI_BD_COUNT - 1].bd_nextp = 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void ring_desc_ring_free(struct pic32_sqi *sqi)
|
|
{
|
|
dma_free_coherent(&sqi->master->dev,
|
|
sizeof(struct buf_desc) * PESQI_BD_COUNT,
|
|
sqi->bd, sqi->bd_dma);
|
|
kfree(sqi->ring);
|
|
}
|
|
|
|
static void pic32_sqi_hw_init(struct pic32_sqi *sqi)
|
|
{
|
|
unsigned long flags;
|
|
u32 val;
|
|
|
|
/* Soft-reset of PESQI controller triggers interrupt.
|
|
* We are not yet ready to handle them so disable CPU
|
|
* interrupt for the time being.
|
|
*/
|
|
local_irq_save(flags);
|
|
|
|
/* assert soft-reset */
|
|
writel(PESQI_SOFT_RESET, sqi->regs + PESQI_CONF_REG);
|
|
|
|
/* wait until clear */
|
|
readl_poll_timeout_atomic(sqi->regs + PESQI_CONF_REG, val,
|
|
!(val & PESQI_SOFT_RESET), 1, 5000);
|
|
|
|
/* disable all interrupts */
|
|
pic32_sqi_disable_int(sqi);
|
|
|
|
/* Now it is safe to enable back CPU interrupt */
|
|
local_irq_restore(flags);
|
|
|
|
/* tx and rx fifo interrupt threshold */
|
|
val = readl(sqi->regs + PESQI_CMD_THRES_REG);
|
|
val &= ~(PESQI_TXTHR_MASK << PESQI_TXTHR_SHIFT);
|
|
val &= ~(PESQI_RXTHR_MASK << PESQI_RXTHR_SHIFT);
|
|
val |= (1U << PESQI_TXTHR_SHIFT) | (1U << PESQI_RXTHR_SHIFT);
|
|
writel(val, sqi->regs + PESQI_CMD_THRES_REG);
|
|
|
|
val = readl(sqi->regs + PESQI_INT_THRES_REG);
|
|
val &= ~(PESQI_TXTHR_MASK << PESQI_TXTHR_SHIFT);
|
|
val &= ~(PESQI_RXTHR_MASK << PESQI_RXTHR_SHIFT);
|
|
val |= (1U << PESQI_TXTHR_SHIFT) | (1U << PESQI_RXTHR_SHIFT);
|
|
writel(val, sqi->regs + PESQI_INT_THRES_REG);
|
|
|
|
/* default configuration */
|
|
val = readl(sqi->regs + PESQI_CONF_REG);
|
|
|
|
/* set mode: DMA */
|
|
val &= ~PESQI_MODE;
|
|
val |= PESQI_MODE_DMA << PESQI_MODE_SHIFT;
|
|
writel(val, sqi->regs + PESQI_CONF_REG);
|
|
|
|
/* DATAEN - SQIID0-ID3 */
|
|
val |= PESQI_QUAD_LANE << PESQI_LANES_SHIFT;
|
|
|
|
/* burst/INCR4 enable */
|
|
val |= PESQI_BURST_EN;
|
|
|
|
/* CSEN - all CS */
|
|
val |= 3U << PESQI_CSEN_SHIFT;
|
|
writel(val, sqi->regs + PESQI_CONF_REG);
|
|
|
|
/* write poll count */
|
|
writel(0, sqi->regs + PESQI_BD_POLL_CTRL_REG);
|
|
|
|
sqi->cur_speed = 0;
|
|
sqi->cur_mode = -1;
|
|
}
|
|
|
|
static int pic32_sqi_probe(struct platform_device *pdev)
|
|
{
|
|
struct spi_master *master;
|
|
struct pic32_sqi *sqi;
|
|
struct resource *reg;
|
|
int ret;
|
|
|
|
master = spi_alloc_master(&pdev->dev, sizeof(*sqi));
|
|
if (!master)
|
|
return -ENOMEM;
|
|
|
|
sqi = spi_master_get_devdata(master);
|
|
sqi->master = master;
|
|
|
|
reg = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
sqi->regs = devm_ioremap_resource(&pdev->dev, reg);
|
|
if (IS_ERR(sqi->regs)) {
|
|
ret = PTR_ERR(sqi->regs);
|
|
goto err_free_master;
|
|
}
|
|
|
|
/* irq */
|
|
sqi->irq = platform_get_irq(pdev, 0);
|
|
if (sqi->irq < 0) {
|
|
dev_err(&pdev->dev, "no irq found\n");
|
|
ret = sqi->irq;
|
|
goto err_free_master;
|
|
}
|
|
|
|
/* clocks */
|
|
sqi->sys_clk = devm_clk_get(&pdev->dev, "reg_ck");
|
|
if (IS_ERR(sqi->sys_clk)) {
|
|
ret = PTR_ERR(sqi->sys_clk);
|
|
dev_err(&pdev->dev, "no sys_clk ?\n");
|
|
goto err_free_master;
|
|
}
|
|
|
|
sqi->base_clk = devm_clk_get(&pdev->dev, "spi_ck");
|
|
if (IS_ERR(sqi->base_clk)) {
|
|
ret = PTR_ERR(sqi->base_clk);
|
|
dev_err(&pdev->dev, "no base clk ?\n");
|
|
goto err_free_master;
|
|
}
|
|
|
|
ret = clk_prepare_enable(sqi->sys_clk);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "sys clk enable failed\n");
|
|
goto err_free_master;
|
|
}
|
|
|
|
ret = clk_prepare_enable(sqi->base_clk);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "base clk enable failed\n");
|
|
clk_disable_unprepare(sqi->sys_clk);
|
|
goto err_free_master;
|
|
}
|
|
|
|
init_completion(&sqi->xfer_done);
|
|
|
|
/* initialize hardware */
|
|
pic32_sqi_hw_init(sqi);
|
|
|
|
/* allocate buffers & descriptors */
|
|
ret = ring_desc_ring_alloc(sqi);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "ring alloc failed\n");
|
|
goto err_disable_clk;
|
|
}
|
|
|
|
/* install irq handlers */
|
|
ret = request_irq(sqi->irq, pic32_sqi_isr, 0,
|
|
dev_name(&pdev->dev), sqi);
|
|
if (ret < 0) {
|
|
dev_err(&pdev->dev, "request_irq(%d), failed\n", sqi->irq);
|
|
goto err_free_ring;
|
|
}
|
|
|
|
/* register master */
|
|
master->num_chipselect = 2;
|
|
master->max_speed_hz = clk_get_rate(sqi->base_clk);
|
|
master->dma_alignment = 32;
|
|
master->max_dma_len = PESQI_BD_BUF_LEN_MAX;
|
|
master->dev.of_node = pdev->dev.of_node;
|
|
master->mode_bits = SPI_MODE_3 | SPI_MODE_0 | SPI_TX_DUAL |
|
|
SPI_RX_DUAL | SPI_TX_QUAD | SPI_RX_QUAD;
|
|
master->flags = SPI_MASTER_HALF_DUPLEX;
|
|
master->can_dma = pic32_sqi_can_dma;
|
|
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 32);
|
|
master->transfer_one_message = pic32_sqi_one_message;
|
|
master->prepare_transfer_hardware = pic32_sqi_prepare_hardware;
|
|
master->unprepare_transfer_hardware = pic32_sqi_unprepare_hardware;
|
|
|
|
ret = devm_spi_register_master(&pdev->dev, master);
|
|
if (ret) {
|
|
dev_err(&master->dev, "failed registering spi master\n");
|
|
free_irq(sqi->irq, sqi);
|
|
goto err_free_ring;
|
|
}
|
|
|
|
platform_set_drvdata(pdev, sqi);
|
|
|
|
return 0;
|
|
|
|
err_free_ring:
|
|
ring_desc_ring_free(sqi);
|
|
|
|
err_disable_clk:
|
|
clk_disable_unprepare(sqi->base_clk);
|
|
clk_disable_unprepare(sqi->sys_clk);
|
|
|
|
err_free_master:
|
|
spi_master_put(master);
|
|
return ret;
|
|
}
|
|
|
|
static int pic32_sqi_remove(struct platform_device *pdev)
|
|
{
|
|
struct pic32_sqi *sqi = platform_get_drvdata(pdev);
|
|
|
|
/* release resources */
|
|
free_irq(sqi->irq, sqi);
|
|
ring_desc_ring_free(sqi);
|
|
|
|
/* disable clk */
|
|
clk_disable_unprepare(sqi->base_clk);
|
|
clk_disable_unprepare(sqi->sys_clk);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct of_device_id pic32_sqi_of_ids[] = {
|
|
{.compatible = "microchip,pic32mzda-sqi",},
|
|
{},
|
|
};
|
|
MODULE_DEVICE_TABLE(of, pic32_sqi_of_ids);
|
|
|
|
static struct platform_driver pic32_sqi_driver = {
|
|
.driver = {
|
|
.name = "sqi-pic32",
|
|
.of_match_table = of_match_ptr(pic32_sqi_of_ids),
|
|
},
|
|
.probe = pic32_sqi_probe,
|
|
.remove = pic32_sqi_remove,
|
|
};
|
|
|
|
module_platform_driver(pic32_sqi_driver);
|
|
|
|
MODULE_AUTHOR("Purna Chandra Mandal <purna.mandal@microchip.com>");
|
|
MODULE_DESCRIPTION("Microchip SPI driver for PIC32 SQI controller.");
|
|
MODULE_LICENSE("GPL v2");
|