// SPDX-License-Identifier: GPL-2.0-only // // Driver for Cadence QSPI Controller // // Copyright Altera Corporation (C) 2012-2014. All rights reserved. // Copyright Intel Corporation (C) 2019-2020. All rights reserved. // Copyright (C) 2020 Texas Instruments Incorporated - http://www.ti.com #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define CQSPI_NAME "cadence-qspi" #define CQSPI_MAX_CHIPSELECT 16 /* Quirks */ #define CQSPI_NEEDS_WR_DELAY BIT(0) #define CQSPI_DISABLE_DAC_MODE BIT(1) /* Capabilities */ #define CQSPI_SUPPORTS_OCTAL BIT(0) struct cqspi_st; struct cqspi_flash_pdata { struct cqspi_st *cqspi; u32 clk_rate; u32 read_delay; u32 tshsl_ns; u32 tsd2d_ns; u32 tchsh_ns; u32 tslch_ns; u8 inst_width; u8 addr_width; u8 data_width; u8 cs; }; struct cqspi_st { struct platform_device *pdev; struct clk *clk; unsigned int sclk; void __iomem *iobase; void __iomem *ahb_base; resource_size_t ahb_size; struct completion transfer_complete; struct dma_chan *rx_chan; struct completion rx_dma_complete; dma_addr_t mmap_phys_base; int current_cs; unsigned long master_ref_clk_hz; bool is_decoded_cs; u32 fifo_depth; u32 fifo_width; bool rclk_en; u32 trigger_address; u32 wr_delay; bool use_direct_mode; struct cqspi_flash_pdata f_pdata[CQSPI_MAX_CHIPSELECT]; }; struct cqspi_driver_platdata { u32 hwcaps_mask; u8 quirks; }; /* Operation timeout value */ #define CQSPI_TIMEOUT_MS 500 #define CQSPI_READ_TIMEOUT_MS 10 /* Instruction type */ #define CQSPI_INST_TYPE_SINGLE 0 #define CQSPI_INST_TYPE_DUAL 1 #define CQSPI_INST_TYPE_QUAD 2 #define CQSPI_INST_TYPE_OCTAL 3 #define CQSPI_DUMMY_CLKS_PER_BYTE 8 #define CQSPI_DUMMY_BYTES_MAX 4 #define CQSPI_DUMMY_CLKS_MAX 31 #define CQSPI_STIG_DATA_LEN_MAX 8 /* Register map */ #define CQSPI_REG_CONFIG 0x00 #define CQSPI_REG_CONFIG_ENABLE_MASK BIT(0) #define CQSPI_REG_CONFIG_ENB_DIR_ACC_CTRL BIT(7) #define CQSPI_REG_CONFIG_DECODE_MASK BIT(9) #define CQSPI_REG_CONFIG_CHIPSELECT_LSB 10 #define CQSPI_REG_CONFIG_DMA_MASK BIT(15) #define CQSPI_REG_CONFIG_BAUD_LSB 19 #define CQSPI_REG_CONFIG_IDLE_LSB 31 #define CQSPI_REG_CONFIG_CHIPSELECT_MASK 0xF #define CQSPI_REG_CONFIG_BAUD_MASK 0xF #define CQSPI_REG_RD_INSTR 0x04 #define CQSPI_REG_RD_INSTR_OPCODE_LSB 0 #define CQSPI_REG_RD_INSTR_TYPE_INSTR_LSB 8 #define CQSPI_REG_RD_INSTR_TYPE_ADDR_LSB 12 #define CQSPI_REG_RD_INSTR_TYPE_DATA_LSB 16 #define CQSPI_REG_RD_INSTR_MODE_EN_LSB 20 #define CQSPI_REG_RD_INSTR_DUMMY_LSB 24 #define CQSPI_REG_RD_INSTR_TYPE_INSTR_MASK 0x3 #define CQSPI_REG_RD_INSTR_TYPE_ADDR_MASK 0x3 #define CQSPI_REG_RD_INSTR_TYPE_DATA_MASK 0x3 #define CQSPI_REG_RD_INSTR_DUMMY_MASK 0x1F #define CQSPI_REG_WR_INSTR 0x08 #define CQSPI_REG_WR_INSTR_OPCODE_LSB 0 #define CQSPI_REG_WR_INSTR_TYPE_ADDR_LSB 12 #define CQSPI_REG_WR_INSTR_TYPE_DATA_LSB 16 #define CQSPI_REG_DELAY 0x0C #define CQSPI_REG_DELAY_TSLCH_LSB 0 #define CQSPI_REG_DELAY_TCHSH_LSB 8 #define CQSPI_REG_DELAY_TSD2D_LSB 16 #define CQSPI_REG_DELAY_TSHSL_LSB 24 #define CQSPI_REG_DELAY_TSLCH_MASK 0xFF #define CQSPI_REG_DELAY_TCHSH_MASK 0xFF #define CQSPI_REG_DELAY_TSD2D_MASK 0xFF #define CQSPI_REG_DELAY_TSHSL_MASK 0xFF #define CQSPI_REG_READCAPTURE 0x10 #define CQSPI_REG_READCAPTURE_BYPASS_LSB 0 #define CQSPI_REG_READCAPTURE_DELAY_LSB 1 #define CQSPI_REG_READCAPTURE_DELAY_MASK 0xF #define CQSPI_REG_SIZE 0x14 #define CQSPI_REG_SIZE_ADDRESS_LSB 0 #define CQSPI_REG_SIZE_PAGE_LSB 4 #define CQSPI_REG_SIZE_BLOCK_LSB 16 #define CQSPI_REG_SIZE_ADDRESS_MASK 0xF #define CQSPI_REG_SIZE_PAGE_MASK 0xFFF #define CQSPI_REG_SIZE_BLOCK_MASK 0x3F #define CQSPI_REG_SRAMPARTITION 0x18 #define CQSPI_REG_INDIRECTTRIGGER 0x1C #define CQSPI_REG_DMA 0x20 #define CQSPI_REG_DMA_SINGLE_LSB 0 #define CQSPI_REG_DMA_BURST_LSB 8 #define CQSPI_REG_DMA_SINGLE_MASK 0xFF #define CQSPI_REG_DMA_BURST_MASK 0xFF #define CQSPI_REG_REMAP 0x24 #define CQSPI_REG_MODE_BIT 0x28 #define CQSPI_REG_SDRAMLEVEL 0x2C #define CQSPI_REG_SDRAMLEVEL_RD_LSB 0 #define CQSPI_REG_SDRAMLEVEL_WR_LSB 16 #define CQSPI_REG_SDRAMLEVEL_RD_MASK 0xFFFF #define CQSPI_REG_SDRAMLEVEL_WR_MASK 0xFFFF #define CQSPI_REG_IRQSTATUS 0x40 #define CQSPI_REG_IRQMASK 0x44 #define CQSPI_REG_INDIRECTRD 0x60 #define CQSPI_REG_INDIRECTRD_START_MASK BIT(0) #define CQSPI_REG_INDIRECTRD_CANCEL_MASK BIT(1) #define CQSPI_REG_INDIRECTRD_DONE_MASK BIT(5) #define CQSPI_REG_INDIRECTRDWATERMARK 0x64 #define CQSPI_REG_INDIRECTRDSTARTADDR 0x68 #define CQSPI_REG_INDIRECTRDBYTES 0x6C #define CQSPI_REG_CMDCTRL 0x90 #define CQSPI_REG_CMDCTRL_EXECUTE_MASK BIT(0) #define CQSPI_REG_CMDCTRL_INPROGRESS_MASK BIT(1) #define CQSPI_REG_CMDCTRL_WR_BYTES_LSB 12 #define CQSPI_REG_CMDCTRL_WR_EN_LSB 15 #define CQSPI_REG_CMDCTRL_ADD_BYTES_LSB 16 #define CQSPI_REG_CMDCTRL_ADDR_EN_LSB 19 #define CQSPI_REG_CMDCTRL_RD_BYTES_LSB 20 #define CQSPI_REG_CMDCTRL_RD_EN_LSB 23 #define CQSPI_REG_CMDCTRL_OPCODE_LSB 24 #define CQSPI_REG_CMDCTRL_WR_BYTES_MASK 0x7 #define CQSPI_REG_CMDCTRL_ADD_BYTES_MASK 0x3 #define CQSPI_REG_CMDCTRL_RD_BYTES_MASK 0x7 #define CQSPI_REG_INDIRECTWR 0x70 #define CQSPI_REG_INDIRECTWR_START_MASK BIT(0) #define CQSPI_REG_INDIRECTWR_CANCEL_MASK BIT(1) #define CQSPI_REG_INDIRECTWR_DONE_MASK BIT(5) #define CQSPI_REG_INDIRECTWRWATERMARK 0x74 #define CQSPI_REG_INDIRECTWRSTARTADDR 0x78 #define CQSPI_REG_INDIRECTWRBYTES 0x7C #define CQSPI_REG_CMDADDRESS 0x94 #define CQSPI_REG_CMDREADDATALOWER 0xA0 #define CQSPI_REG_CMDREADDATAUPPER 0xA4 #define CQSPI_REG_CMDWRITEDATALOWER 0xA8 #define CQSPI_REG_CMDWRITEDATAUPPER 0xAC /* Interrupt status bits */ #define CQSPI_REG_IRQ_MODE_ERR BIT(0) #define CQSPI_REG_IRQ_UNDERFLOW BIT(1) #define CQSPI_REG_IRQ_IND_COMP BIT(2) #define CQSPI_REG_IRQ_IND_RD_REJECT BIT(3) #define CQSPI_REG_IRQ_WR_PROTECTED_ERR BIT(4) #define CQSPI_REG_IRQ_ILLEGAL_AHB_ERR BIT(5) #define CQSPI_REG_IRQ_WATERMARK BIT(6) #define CQSPI_REG_IRQ_IND_SRAM_FULL BIT(12) #define CQSPI_IRQ_MASK_RD (CQSPI_REG_IRQ_WATERMARK | \ CQSPI_REG_IRQ_IND_SRAM_FULL | \ CQSPI_REG_IRQ_IND_COMP) #define CQSPI_IRQ_MASK_WR (CQSPI_REG_IRQ_IND_COMP | \ CQSPI_REG_IRQ_WATERMARK | \ CQSPI_REG_IRQ_UNDERFLOW) #define CQSPI_IRQ_STATUS_MASK 0x1FFFF static int cqspi_wait_for_bit(void __iomem *reg, const u32 mask, bool clr) { u32 val; return readl_relaxed_poll_timeout(reg, val, (((clr ? ~val : val) & mask) == mask), 10, CQSPI_TIMEOUT_MS * 1000); } static bool cqspi_is_idle(struct cqspi_st *cqspi) { u32 reg = readl(cqspi->iobase + CQSPI_REG_CONFIG); return reg & (1 << CQSPI_REG_CONFIG_IDLE_LSB); } static u32 cqspi_get_rd_sram_level(struct cqspi_st *cqspi) { u32 reg = readl(cqspi->iobase + CQSPI_REG_SDRAMLEVEL); reg >>= CQSPI_REG_SDRAMLEVEL_RD_LSB; return reg & CQSPI_REG_SDRAMLEVEL_RD_MASK; } static irqreturn_t cqspi_irq_handler(int this_irq, void *dev) { struct cqspi_st *cqspi = dev; unsigned int irq_status; /* Read interrupt status */ irq_status = readl(cqspi->iobase + CQSPI_REG_IRQSTATUS); /* Clear interrupt */ writel(irq_status, cqspi->iobase + CQSPI_REG_IRQSTATUS); irq_status &= CQSPI_IRQ_MASK_RD | CQSPI_IRQ_MASK_WR; if (irq_status) complete(&cqspi->transfer_complete); return IRQ_HANDLED; } static unsigned int cqspi_calc_rdreg(struct cqspi_flash_pdata *f_pdata) { u32 rdreg = 0; rdreg |= f_pdata->inst_width << CQSPI_REG_RD_INSTR_TYPE_INSTR_LSB; rdreg |= f_pdata->addr_width << CQSPI_REG_RD_INSTR_TYPE_ADDR_LSB; rdreg |= f_pdata->data_width << CQSPI_REG_RD_INSTR_TYPE_DATA_LSB; return rdreg; } static int cqspi_wait_idle(struct cqspi_st *cqspi) { const unsigned int poll_idle_retry = 3; unsigned int count = 0; unsigned long timeout; timeout = jiffies + msecs_to_jiffies(CQSPI_TIMEOUT_MS); while (1) { /* * Read few times in succession to ensure the controller * is indeed idle, that is, the bit does not transition * low again. */ if (cqspi_is_idle(cqspi)) count++; else count = 0; if (count >= poll_idle_retry) return 0; if (time_after(jiffies, timeout)) { /* Timeout, in busy mode. */ dev_err(&cqspi->pdev->dev, "QSPI is still busy after %dms timeout.\n", CQSPI_TIMEOUT_MS); return -ETIMEDOUT; } cpu_relax(); } } static int cqspi_exec_flash_cmd(struct cqspi_st *cqspi, unsigned int reg) { void __iomem *reg_base = cqspi->iobase; int ret; /* Write the CMDCTRL without start execution. */ writel(reg, reg_base + CQSPI_REG_CMDCTRL); /* Start execute */ reg |= CQSPI_REG_CMDCTRL_EXECUTE_MASK; writel(reg, reg_base + CQSPI_REG_CMDCTRL); /* Polling for completion. */ ret = cqspi_wait_for_bit(reg_base + CQSPI_REG_CMDCTRL, CQSPI_REG_CMDCTRL_INPROGRESS_MASK, 1); if (ret) { dev_err(&cqspi->pdev->dev, "Flash command execution timed out.\n"); return ret; } /* Polling QSPI idle status. */ return cqspi_wait_idle(cqspi); } static int cqspi_command_read(struct cqspi_flash_pdata *f_pdata, const struct spi_mem_op *op) { struct cqspi_st *cqspi = f_pdata->cqspi; void __iomem *reg_base = cqspi->iobase; u8 *rxbuf = op->data.buf.in; u8 opcode = op->cmd.opcode; size_t n_rx = op->data.nbytes; unsigned int rdreg; unsigned int reg; size_t read_len; int status; if (!n_rx || n_rx > CQSPI_STIG_DATA_LEN_MAX || !rxbuf) { dev_err(&cqspi->pdev->dev, "Invalid input argument, len %zu rxbuf 0x%p\n", n_rx, rxbuf); return -EINVAL; } reg = opcode << CQSPI_REG_CMDCTRL_OPCODE_LSB; rdreg = cqspi_calc_rdreg(f_pdata); writel(rdreg, reg_base + CQSPI_REG_RD_INSTR); reg |= (0x1 << CQSPI_REG_CMDCTRL_RD_EN_LSB); /* 0 means 1 byte. */ reg |= (((n_rx - 1) & CQSPI_REG_CMDCTRL_RD_BYTES_MASK) << CQSPI_REG_CMDCTRL_RD_BYTES_LSB); status = cqspi_exec_flash_cmd(cqspi, reg); if (status) return status; reg = readl(reg_base + CQSPI_REG_CMDREADDATALOWER); /* Put the read value into rx_buf */ read_len = (n_rx > 4) ? 4 : n_rx; memcpy(rxbuf, ®, read_len); rxbuf += read_len; if (n_rx > 4) { reg = readl(reg_base + CQSPI_REG_CMDREADDATAUPPER); read_len = n_rx - read_len; memcpy(rxbuf, ®, read_len); } return 0; } static int cqspi_command_write(struct cqspi_flash_pdata *f_pdata, const struct spi_mem_op *op) { struct cqspi_st *cqspi = f_pdata->cqspi; void __iomem *reg_base = cqspi->iobase; const u8 opcode = op->cmd.opcode; const u8 *txbuf = op->data.buf.out; size_t n_tx = op->data.nbytes; unsigned int reg; unsigned int data; size_t write_len; if (n_tx > CQSPI_STIG_DATA_LEN_MAX || (n_tx && !txbuf)) { dev_err(&cqspi->pdev->dev, "Invalid input argument, cmdlen %zu txbuf 0x%p\n", n_tx, txbuf); return -EINVAL; } reg = opcode << CQSPI_REG_CMDCTRL_OPCODE_LSB; if (op->addr.nbytes) { reg |= (0x1 << CQSPI_REG_CMDCTRL_ADDR_EN_LSB); reg |= ((op->addr.nbytes - 1) & CQSPI_REG_CMDCTRL_ADD_BYTES_MASK) << CQSPI_REG_CMDCTRL_ADD_BYTES_LSB; writel(op->addr.val, reg_base + CQSPI_REG_CMDADDRESS); } if (n_tx) { reg |= (0x1 << CQSPI_REG_CMDCTRL_WR_EN_LSB); reg |= ((n_tx - 1) & CQSPI_REG_CMDCTRL_WR_BYTES_MASK) << CQSPI_REG_CMDCTRL_WR_BYTES_LSB; data = 0; write_len = (n_tx > 4) ? 4 : n_tx; memcpy(&data, txbuf, write_len); txbuf += write_len; writel(data, reg_base + CQSPI_REG_CMDWRITEDATALOWER); if (n_tx > 4) { data = 0; write_len = n_tx - 4; memcpy(&data, txbuf, write_len); writel(data, reg_base + CQSPI_REG_CMDWRITEDATAUPPER); } } return cqspi_exec_flash_cmd(cqspi, reg); } static int cqspi_read_setup(struct cqspi_flash_pdata *f_pdata, const struct spi_mem_op *op) { struct cqspi_st *cqspi = f_pdata->cqspi; void __iomem *reg_base = cqspi->iobase; unsigned int dummy_clk = 0; unsigned int reg; reg = op->cmd.opcode << CQSPI_REG_RD_INSTR_OPCODE_LSB; reg |= cqspi_calc_rdreg(f_pdata); /* Setup dummy clock cycles */ dummy_clk = op->dummy.nbytes * 8; if (dummy_clk > CQSPI_DUMMY_CLKS_MAX) dummy_clk = CQSPI_DUMMY_CLKS_MAX; if (dummy_clk) reg |= (dummy_clk & CQSPI_REG_RD_INSTR_DUMMY_MASK) << CQSPI_REG_RD_INSTR_DUMMY_LSB; writel(reg, reg_base + CQSPI_REG_RD_INSTR); /* Set address width */ reg = readl(reg_base + CQSPI_REG_SIZE); reg &= ~CQSPI_REG_SIZE_ADDRESS_MASK; reg |= (op->addr.nbytes - 1); writel(reg, reg_base + CQSPI_REG_SIZE); return 0; } static int cqspi_indirect_read_execute(struct cqspi_flash_pdata *f_pdata, u8 *rxbuf, loff_t from_addr, const size_t n_rx) { struct cqspi_st *cqspi = f_pdata->cqspi; struct device *dev = &cqspi->pdev->dev; void __iomem *reg_base = cqspi->iobase; void __iomem *ahb_base = cqspi->ahb_base; unsigned int remaining = n_rx; unsigned int mod_bytes = n_rx % 4; unsigned int bytes_to_read = 0; u8 *rxbuf_end = rxbuf + n_rx; int ret = 0; writel(from_addr, reg_base + CQSPI_REG_INDIRECTRDSTARTADDR); writel(remaining, reg_base + CQSPI_REG_INDIRECTRDBYTES); /* Clear all interrupts. */ writel(CQSPI_IRQ_STATUS_MASK, reg_base + CQSPI_REG_IRQSTATUS); writel(CQSPI_IRQ_MASK_RD, reg_base + CQSPI_REG_IRQMASK); reinit_completion(&cqspi->transfer_complete); writel(CQSPI_REG_INDIRECTRD_START_MASK, reg_base + CQSPI_REG_INDIRECTRD); while (remaining > 0) { if (!wait_for_completion_timeout(&cqspi->transfer_complete, msecs_to_jiffies(CQSPI_READ_TIMEOUT_MS))) ret = -ETIMEDOUT; bytes_to_read = cqspi_get_rd_sram_level(cqspi); if (ret && bytes_to_read == 0) { dev_err(dev, "Indirect read timeout, no bytes\n"); goto failrd; } while (bytes_to_read != 0) { unsigned int word_remain = round_down(remaining, 4); bytes_to_read *= cqspi->fifo_width; bytes_to_read = bytes_to_read > remaining ? remaining : bytes_to_read; bytes_to_read = round_down(bytes_to_read, 4); /* Read 4 byte word chunks then single bytes */ if (bytes_to_read) { ioread32_rep(ahb_base, rxbuf, (bytes_to_read / 4)); } else if (!word_remain && mod_bytes) { unsigned int temp = ioread32(ahb_base); bytes_to_read = mod_bytes; memcpy(rxbuf, &temp, min((unsigned int) (rxbuf_end - rxbuf), bytes_to_read)); } rxbuf += bytes_to_read; remaining -= bytes_to_read; bytes_to_read = cqspi_get_rd_sram_level(cqspi); } if (remaining > 0) reinit_completion(&cqspi->transfer_complete); } /* Check indirect done status */ ret = cqspi_wait_for_bit(reg_base + CQSPI_REG_INDIRECTRD, CQSPI_REG_INDIRECTRD_DONE_MASK, 0); if (ret) { dev_err(dev, "Indirect read completion error (%i)\n", ret); goto failrd; } /* Disable interrupt */ writel(0, reg_base + CQSPI_REG_IRQMASK); /* Clear indirect completion status */ writel(CQSPI_REG_INDIRECTRD_DONE_MASK, reg_base + CQSPI_REG_INDIRECTRD); return 0; failrd: /* Disable interrupt */ writel(0, reg_base + CQSPI_REG_IRQMASK); /* Cancel the indirect read */ writel(CQSPI_REG_INDIRECTWR_CANCEL_MASK, reg_base + CQSPI_REG_INDIRECTRD); return ret; } static int cqspi_write_setup(struct cqspi_flash_pdata *f_pdata, const struct spi_mem_op *op) { unsigned int reg; struct cqspi_st *cqspi = f_pdata->cqspi; void __iomem *reg_base = cqspi->iobase; /* Set opcode. */ reg = op->cmd.opcode << CQSPI_REG_WR_INSTR_OPCODE_LSB; writel(reg, reg_base + CQSPI_REG_WR_INSTR); reg = cqspi_calc_rdreg(f_pdata); writel(reg, reg_base + CQSPI_REG_RD_INSTR); reg = readl(reg_base + CQSPI_REG_SIZE); reg &= ~CQSPI_REG_SIZE_ADDRESS_MASK; reg |= (op->addr.nbytes - 1); writel(reg, reg_base + CQSPI_REG_SIZE); return 0; } static int cqspi_indirect_write_execute(struct cqspi_flash_pdata *f_pdata, loff_t to_addr, const u8 *txbuf, const size_t n_tx) { struct cqspi_st *cqspi = f_pdata->cqspi; struct device *dev = &cqspi->pdev->dev; void __iomem *reg_base = cqspi->iobase; unsigned int remaining = n_tx; unsigned int write_bytes; int ret; writel(to_addr, reg_base + CQSPI_REG_INDIRECTWRSTARTADDR); writel(remaining, reg_base + CQSPI_REG_INDIRECTWRBYTES); /* Clear all interrupts. */ writel(CQSPI_IRQ_STATUS_MASK, reg_base + CQSPI_REG_IRQSTATUS); writel(CQSPI_IRQ_MASK_WR, reg_base + CQSPI_REG_IRQMASK); reinit_completion(&cqspi->transfer_complete); writel(CQSPI_REG_INDIRECTWR_START_MASK, reg_base + CQSPI_REG_INDIRECTWR); /* * As per 66AK2G02 TRM SPRUHY8F section 11.15.5.3 Indirect Access * Controller programming sequence, couple of cycles of * QSPI_REF_CLK delay is required for the above bit to * be internally synchronized by the QSPI module. Provide 5 * cycles of delay. */ if (cqspi->wr_delay) ndelay(cqspi->wr_delay); while (remaining > 0) { size_t write_words, mod_bytes; write_bytes = remaining; write_words = write_bytes / 4; mod_bytes = write_bytes % 4; /* Write 4 bytes at a time then single bytes. */ if (write_words) { iowrite32_rep(cqspi->ahb_base, txbuf, write_words); txbuf += (write_words * 4); } if (mod_bytes) { unsigned int temp = 0xFFFFFFFF; memcpy(&temp, txbuf, mod_bytes); iowrite32(temp, cqspi->ahb_base); txbuf += mod_bytes; } if (!wait_for_completion_timeout(&cqspi->transfer_complete, msecs_to_jiffies(CQSPI_TIMEOUT_MS))) { dev_err(dev, "Indirect write timeout\n"); ret = -ETIMEDOUT; goto failwr; } remaining -= write_bytes; if (remaining > 0) reinit_completion(&cqspi->transfer_complete); } /* Check indirect done status */ ret = cqspi_wait_for_bit(reg_base + CQSPI_REG_INDIRECTWR, CQSPI_REG_INDIRECTWR_DONE_MASK, 0); if (ret) { dev_err(dev, "Indirect write completion error (%i)\n", ret); goto failwr; } /* Disable interrupt. */ writel(0, reg_base + CQSPI_REG_IRQMASK); /* Clear indirect completion status */ writel(CQSPI_REG_INDIRECTWR_DONE_MASK, reg_base + CQSPI_REG_INDIRECTWR); cqspi_wait_idle(cqspi); return 0; failwr: /* Disable interrupt. */ writel(0, reg_base + CQSPI_REG_IRQMASK); /* Cancel the indirect write */ writel(CQSPI_REG_INDIRECTWR_CANCEL_MASK, reg_base + CQSPI_REG_INDIRECTWR); return ret; } static void cqspi_chipselect(struct cqspi_flash_pdata *f_pdata) { struct cqspi_st *cqspi = f_pdata->cqspi; void __iomem *reg_base = cqspi->iobase; unsigned int chip_select = f_pdata->cs; unsigned int reg; reg = readl(reg_base + CQSPI_REG_CONFIG); if (cqspi->is_decoded_cs) { reg |= CQSPI_REG_CONFIG_DECODE_MASK; } else { reg &= ~CQSPI_REG_CONFIG_DECODE_MASK; /* Convert CS if without decoder. * CS0 to 4b'1110 * CS1 to 4b'1101 * CS2 to 4b'1011 * CS3 to 4b'0111 */ chip_select = 0xF & ~(1 << chip_select); } reg &= ~(CQSPI_REG_CONFIG_CHIPSELECT_MASK << CQSPI_REG_CONFIG_CHIPSELECT_LSB); reg |= (chip_select & CQSPI_REG_CONFIG_CHIPSELECT_MASK) << CQSPI_REG_CONFIG_CHIPSELECT_LSB; writel(reg, reg_base + CQSPI_REG_CONFIG); } static unsigned int calculate_ticks_for_ns(const unsigned int ref_clk_hz, const unsigned int ns_val) { unsigned int ticks; ticks = ref_clk_hz / 1000; /* kHz */ ticks = DIV_ROUND_UP(ticks * ns_val, 1000000); return ticks; } static void cqspi_delay(struct cqspi_flash_pdata *f_pdata) { struct cqspi_st *cqspi = f_pdata->cqspi; void __iomem *iobase = cqspi->iobase; const unsigned int ref_clk_hz = cqspi->master_ref_clk_hz; unsigned int tshsl, tchsh, tslch, tsd2d; unsigned int reg; unsigned int tsclk; /* calculate the number of ref ticks for one sclk tick */ tsclk = DIV_ROUND_UP(ref_clk_hz, cqspi->sclk); tshsl = calculate_ticks_for_ns(ref_clk_hz, f_pdata->tshsl_ns); /* this particular value must be at least one sclk */ if (tshsl < tsclk) tshsl = tsclk; tchsh = calculate_ticks_for_ns(ref_clk_hz, f_pdata->tchsh_ns); tslch = calculate_ticks_for_ns(ref_clk_hz, f_pdata->tslch_ns); tsd2d = calculate_ticks_for_ns(ref_clk_hz, f_pdata->tsd2d_ns); reg = (tshsl & CQSPI_REG_DELAY_TSHSL_MASK) << CQSPI_REG_DELAY_TSHSL_LSB; reg |= (tchsh & CQSPI_REG_DELAY_TCHSH_MASK) << CQSPI_REG_DELAY_TCHSH_LSB; reg |= (tslch & CQSPI_REG_DELAY_TSLCH_MASK) << CQSPI_REG_DELAY_TSLCH_LSB; reg |= (tsd2d & CQSPI_REG_DELAY_TSD2D_MASK) << CQSPI_REG_DELAY_TSD2D_LSB; writel(reg, iobase + CQSPI_REG_DELAY); } static void cqspi_config_baudrate_div(struct cqspi_st *cqspi) { const unsigned int ref_clk_hz = cqspi->master_ref_clk_hz; void __iomem *reg_base = cqspi->iobase; u32 reg, div; /* Recalculate the baudrate divisor based on QSPI specification. */ div = DIV_ROUND_UP(ref_clk_hz, 2 * cqspi->sclk) - 1; reg = readl(reg_base + CQSPI_REG_CONFIG); reg &= ~(CQSPI_REG_CONFIG_BAUD_MASK << CQSPI_REG_CONFIG_BAUD_LSB); reg |= (div & CQSPI_REG_CONFIG_BAUD_MASK) << CQSPI_REG_CONFIG_BAUD_LSB; writel(reg, reg_base + CQSPI_REG_CONFIG); } static void cqspi_readdata_capture(struct cqspi_st *cqspi, const bool bypass, const unsigned int delay) { void __iomem *reg_base = cqspi->iobase; unsigned int reg; reg = readl(reg_base + CQSPI_REG_READCAPTURE); if (bypass) reg |= (1 << CQSPI_REG_READCAPTURE_BYPASS_LSB); else reg &= ~(1 << CQSPI_REG_READCAPTURE_BYPASS_LSB); reg &= ~(CQSPI_REG_READCAPTURE_DELAY_MASK << CQSPI_REG_READCAPTURE_DELAY_LSB); reg |= (delay & CQSPI_REG_READCAPTURE_DELAY_MASK) << CQSPI_REG_READCAPTURE_DELAY_LSB; writel(reg, reg_base + CQSPI_REG_READCAPTURE); } static void cqspi_controller_enable(struct cqspi_st *cqspi, bool enable) { void __iomem *reg_base = cqspi->iobase; unsigned int reg; reg = readl(reg_base + CQSPI_REG_CONFIG); if (enable) reg |= CQSPI_REG_CONFIG_ENABLE_MASK; else reg &= ~CQSPI_REG_CONFIG_ENABLE_MASK; writel(reg, reg_base + CQSPI_REG_CONFIG); } static void cqspi_configure(struct cqspi_flash_pdata *f_pdata, unsigned long sclk) { struct cqspi_st *cqspi = f_pdata->cqspi; int switch_cs = (cqspi->current_cs != f_pdata->cs); int switch_ck = (cqspi->sclk != sclk); if (switch_cs || switch_ck) cqspi_controller_enable(cqspi, 0); /* Switch chip select. */ if (switch_cs) { cqspi->current_cs = f_pdata->cs; cqspi_chipselect(f_pdata); } /* Setup baudrate divisor and delays */ if (switch_ck) { cqspi->sclk = sclk; cqspi_config_baudrate_div(cqspi); cqspi_delay(f_pdata); cqspi_readdata_capture(cqspi, !cqspi->rclk_en, f_pdata->read_delay); } if (switch_cs || switch_ck) cqspi_controller_enable(cqspi, 1); } static int cqspi_set_protocol(struct cqspi_flash_pdata *f_pdata, const struct spi_mem_op *op) { f_pdata->inst_width = CQSPI_INST_TYPE_SINGLE; f_pdata->addr_width = CQSPI_INST_TYPE_SINGLE; f_pdata->data_width = CQSPI_INST_TYPE_SINGLE; if (op->data.dir == SPI_MEM_DATA_IN) { switch (op->data.buswidth) { case 1: f_pdata->data_width = CQSPI_INST_TYPE_SINGLE; break; case 2: f_pdata->data_width = CQSPI_INST_TYPE_DUAL; break; case 4: f_pdata->data_width = CQSPI_INST_TYPE_QUAD; break; case 8: f_pdata->data_width = CQSPI_INST_TYPE_OCTAL; break; default: return -EINVAL; } } return 0; } static ssize_t cqspi_write(struct cqspi_flash_pdata *f_pdata, const struct spi_mem_op *op) { struct cqspi_st *cqspi = f_pdata->cqspi; loff_t to = op->addr.val; size_t len = op->data.nbytes; const u_char *buf = op->data.buf.out; int ret; ret = cqspi_set_protocol(f_pdata, op); if (ret) return ret; ret = cqspi_write_setup(f_pdata, op); if (ret) return ret; if (cqspi->use_direct_mode && ((to + len) <= cqspi->ahb_size)) { memcpy_toio(cqspi->ahb_base + to, buf, len); return cqspi_wait_idle(cqspi); } return cqspi_indirect_write_execute(f_pdata, to, buf, len); } static void cqspi_rx_dma_callback(void *param) { struct cqspi_st *cqspi = param; complete(&cqspi->rx_dma_complete); } static int cqspi_direct_read_execute(struct cqspi_flash_pdata *f_pdata, u_char *buf, loff_t from, size_t len) { struct cqspi_st *cqspi = f_pdata->cqspi; struct device *dev = &cqspi->pdev->dev; enum dma_ctrl_flags flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT; dma_addr_t dma_src = (dma_addr_t)cqspi->mmap_phys_base + from; int ret = 0; struct dma_async_tx_descriptor *tx; dma_cookie_t cookie; dma_addr_t dma_dst; struct device *ddev; if (!cqspi->rx_chan || !virt_addr_valid(buf)) { memcpy_fromio(buf, cqspi->ahb_base + from, len); return 0; } ddev = cqspi->rx_chan->device->dev; dma_dst = dma_map_single(ddev, buf, len, DMA_FROM_DEVICE); if (dma_mapping_error(ddev, dma_dst)) { dev_err(dev, "dma mapping failed\n"); return -ENOMEM; } tx = dmaengine_prep_dma_memcpy(cqspi->rx_chan, dma_dst, dma_src, len, flags); if (!tx) { dev_err(dev, "device_prep_dma_memcpy error\n"); ret = -EIO; goto err_unmap; } tx->callback = cqspi_rx_dma_callback; tx->callback_param = cqspi; cookie = tx->tx_submit(tx); reinit_completion(&cqspi->rx_dma_complete); ret = dma_submit_error(cookie); if (ret) { dev_err(dev, "dma_submit_error %d\n", cookie); ret = -EIO; goto err_unmap; } dma_async_issue_pending(cqspi->rx_chan); if (!wait_for_completion_timeout(&cqspi->rx_dma_complete, msecs_to_jiffies(len))) { dmaengine_terminate_sync(cqspi->rx_chan); dev_err(dev, "DMA wait_for_completion_timeout\n"); ret = -ETIMEDOUT; goto err_unmap; } err_unmap: dma_unmap_single(ddev, dma_dst, len, DMA_FROM_DEVICE); return ret; } static ssize_t cqspi_read(struct cqspi_flash_pdata *f_pdata, const struct spi_mem_op *op) { struct cqspi_st *cqspi = f_pdata->cqspi; loff_t from = op->addr.val; size_t len = op->data.nbytes; u_char *buf = op->data.buf.in; int ret; ret = cqspi_set_protocol(f_pdata, op); if (ret) return ret; ret = cqspi_read_setup(f_pdata, op); if (ret) return ret; if (cqspi->use_direct_mode && ((from + len) <= cqspi->ahb_size)) return cqspi_direct_read_execute(f_pdata, buf, from, len); return cqspi_indirect_read_execute(f_pdata, buf, from, len); } static int cqspi_mem_process(struct spi_mem *mem, const struct spi_mem_op *op) { struct cqspi_st *cqspi = spi_master_get_devdata(mem->spi->master); struct cqspi_flash_pdata *f_pdata; f_pdata = &cqspi->f_pdata[mem->spi->chip_select]; cqspi_configure(f_pdata, mem->spi->max_speed_hz); if (op->data.dir == SPI_MEM_DATA_IN && op->data.buf.in) { if (!op->addr.nbytes) return cqspi_command_read(f_pdata, op); return cqspi_read(f_pdata, op); } if (!op->addr.nbytes || !op->data.buf.out) return cqspi_command_write(f_pdata, op); return cqspi_write(f_pdata, op); } static int cqspi_exec_mem_op(struct spi_mem *mem, const struct spi_mem_op *op) { int ret; ret = cqspi_mem_process(mem, op); if (ret) dev_err(&mem->spi->dev, "operation failed with %d\n", ret); return ret; } static int cqspi_of_get_flash_pdata(struct platform_device *pdev, struct cqspi_flash_pdata *f_pdata, struct device_node *np) { if (of_property_read_u32(np, "cdns,read-delay", &f_pdata->read_delay)) { dev_err(&pdev->dev, "couldn't determine read-delay\n"); return -ENXIO; } if (of_property_read_u32(np, "cdns,tshsl-ns", &f_pdata->tshsl_ns)) { dev_err(&pdev->dev, "couldn't determine tshsl-ns\n"); return -ENXIO; } if (of_property_read_u32(np, "cdns,tsd2d-ns", &f_pdata->tsd2d_ns)) { dev_err(&pdev->dev, "couldn't determine tsd2d-ns\n"); return -ENXIO; } if (of_property_read_u32(np, "cdns,tchsh-ns", &f_pdata->tchsh_ns)) { dev_err(&pdev->dev, "couldn't determine tchsh-ns\n"); return -ENXIO; } if (of_property_read_u32(np, "cdns,tslch-ns", &f_pdata->tslch_ns)) { dev_err(&pdev->dev, "couldn't determine tslch-ns\n"); return -ENXIO; } if (of_property_read_u32(np, "spi-max-frequency", &f_pdata->clk_rate)) { dev_err(&pdev->dev, "couldn't determine spi-max-frequency\n"); return -ENXIO; } return 0; } static int cqspi_of_get_pdata(struct cqspi_st *cqspi) { struct device *dev = &cqspi->pdev->dev; struct device_node *np = dev->of_node; cqspi->is_decoded_cs = of_property_read_bool(np, "cdns,is-decoded-cs"); if (of_property_read_u32(np, "cdns,fifo-depth", &cqspi->fifo_depth)) { dev_err(dev, "couldn't determine fifo-depth\n"); return -ENXIO; } if (of_property_read_u32(np, "cdns,fifo-width", &cqspi->fifo_width)) { dev_err(dev, "couldn't determine fifo-width\n"); return -ENXIO; } if (of_property_read_u32(np, "cdns,trigger-address", &cqspi->trigger_address)) { dev_err(dev, "couldn't determine trigger-address\n"); return -ENXIO; } cqspi->rclk_en = of_property_read_bool(np, "cdns,rclk-en"); return 0; } static void cqspi_controller_init(struct cqspi_st *cqspi) { u32 reg; cqspi_controller_enable(cqspi, 0); /* Configure the remap address register, no remap */ writel(0, cqspi->iobase + CQSPI_REG_REMAP); /* Disable all interrupts. */ writel(0, cqspi->iobase + CQSPI_REG_IRQMASK); /* Configure the SRAM split to 1:1 . */ writel(cqspi->fifo_depth / 2, cqspi->iobase + CQSPI_REG_SRAMPARTITION); /* Load indirect trigger address. */ writel(cqspi->trigger_address, cqspi->iobase + CQSPI_REG_INDIRECTTRIGGER); /* Program read watermark -- 1/2 of the FIFO. */ writel(cqspi->fifo_depth * cqspi->fifo_width / 2, cqspi->iobase + CQSPI_REG_INDIRECTRDWATERMARK); /* Program write watermark -- 1/8 of the FIFO. */ writel(cqspi->fifo_depth * cqspi->fifo_width / 8, cqspi->iobase + CQSPI_REG_INDIRECTWRWATERMARK); /* Enable Direct Access Controller */ reg = readl(cqspi->iobase + CQSPI_REG_CONFIG); reg |= CQSPI_REG_CONFIG_ENB_DIR_ACC_CTRL; writel(reg, cqspi->iobase + CQSPI_REG_CONFIG); cqspi_controller_enable(cqspi, 1); } static int cqspi_request_mmap_dma(struct cqspi_st *cqspi) { dma_cap_mask_t mask; dma_cap_zero(mask); dma_cap_set(DMA_MEMCPY, mask); cqspi->rx_chan = dma_request_chan_by_mask(&mask); if (IS_ERR(cqspi->rx_chan)) { int ret = PTR_ERR(cqspi->rx_chan); if (ret != -EPROBE_DEFER) dev_err(&cqspi->pdev->dev, "No Rx DMA available\n"); cqspi->rx_chan = NULL; return ret; } init_completion(&cqspi->rx_dma_complete); return 0; } static const char *cqspi_get_name(struct spi_mem *mem) { struct cqspi_st *cqspi = spi_master_get_devdata(mem->spi->master); struct device *dev = &cqspi->pdev->dev; return devm_kasprintf(dev, GFP_KERNEL, "%s.%d", dev_name(dev), mem->spi->chip_select); } static const struct spi_controller_mem_ops cqspi_mem_ops = { .exec_op = cqspi_exec_mem_op, .get_name = cqspi_get_name, }; static int cqspi_setup_flash(struct cqspi_st *cqspi) { struct platform_device *pdev = cqspi->pdev; struct device *dev = &pdev->dev; struct device_node *np = dev->of_node; struct cqspi_flash_pdata *f_pdata; unsigned int cs; int ret; /* Get flash device data */ for_each_available_child_of_node(dev->of_node, np) { ret = of_property_read_u32(np, "reg", &cs); if (ret) { dev_err(dev, "Couldn't determine chip select.\n"); return ret; } if (cs >= CQSPI_MAX_CHIPSELECT) { dev_err(dev, "Chip select %d out of range.\n", cs); return -EINVAL; } f_pdata = &cqspi->f_pdata[cs]; f_pdata->cqspi = cqspi; f_pdata->cs = cs; ret = cqspi_of_get_flash_pdata(pdev, f_pdata, np); if (ret) return ret; } return 0; } static int cqspi_probe(struct platform_device *pdev) { const struct cqspi_driver_platdata *ddata; struct reset_control *rstc, *rstc_ocp; struct device *dev = &pdev->dev; struct spi_master *master; struct resource *res_ahb; struct cqspi_st *cqspi; struct resource *res; int ret; int irq; master = spi_alloc_master(&pdev->dev, sizeof(*cqspi)); if (!master) { dev_err(&pdev->dev, "spi_alloc_master failed\n"); return -ENOMEM; } master->mode_bits = SPI_RX_QUAD | SPI_RX_DUAL; master->mem_ops = &cqspi_mem_ops; master->dev.of_node = pdev->dev.of_node; cqspi = spi_master_get_devdata(master); cqspi->pdev = pdev; /* Obtain configuration from OF. */ ret = cqspi_of_get_pdata(cqspi); if (ret) { dev_err(dev, "Cannot get mandatory OF data.\n"); ret = -ENODEV; goto probe_master_put; } /* Obtain QSPI clock. */ cqspi->clk = devm_clk_get(dev, NULL); if (IS_ERR(cqspi->clk)) { dev_err(dev, "Cannot claim QSPI clock.\n"); ret = PTR_ERR(cqspi->clk); goto probe_master_put; } /* Obtain and remap controller address. */ res = platform_get_resource(pdev, IORESOURCE_MEM, 0); cqspi->iobase = devm_ioremap_resource(dev, res); if (IS_ERR(cqspi->iobase)) { dev_err(dev, "Cannot remap controller address.\n"); ret = PTR_ERR(cqspi->iobase); goto probe_master_put; } /* Obtain and remap AHB address. */ res_ahb = platform_get_resource(pdev, IORESOURCE_MEM, 1); cqspi->ahb_base = devm_ioremap_resource(dev, res_ahb); if (IS_ERR(cqspi->ahb_base)) { dev_err(dev, "Cannot remap AHB address.\n"); ret = PTR_ERR(cqspi->ahb_base); goto probe_master_put; } cqspi->mmap_phys_base = (dma_addr_t)res_ahb->start; cqspi->ahb_size = resource_size(res_ahb); init_completion(&cqspi->transfer_complete); /* Obtain IRQ line. */ irq = platform_get_irq(pdev, 0); if (irq < 0) { ret = -ENXIO; goto probe_master_put; } pm_runtime_enable(dev); ret = pm_runtime_get_sync(dev); if (ret < 0) { pm_runtime_put_noidle(dev); goto probe_master_put; } ret = clk_prepare_enable(cqspi->clk); if (ret) { dev_err(dev, "Cannot enable QSPI clock.\n"); goto probe_clk_failed; } /* Obtain QSPI reset control */ rstc = devm_reset_control_get_optional_exclusive(dev, "qspi"); if (IS_ERR(rstc)) { dev_err(dev, "Cannot get QSPI reset.\n"); goto probe_reset_failed; } rstc_ocp = devm_reset_control_get_optional_exclusive(dev, "qspi-ocp"); if (IS_ERR(rstc_ocp)) { dev_err(dev, "Cannot get QSPI OCP reset.\n"); goto probe_reset_failed; } reset_control_assert(rstc); reset_control_deassert(rstc); reset_control_assert(rstc_ocp); reset_control_deassert(rstc_ocp); cqspi->master_ref_clk_hz = clk_get_rate(cqspi->clk); ddata = of_device_get_match_data(dev); if (ddata) { if (ddata->quirks & CQSPI_NEEDS_WR_DELAY) cqspi->wr_delay = 5 * DIV_ROUND_UP(NSEC_PER_SEC, cqspi->master_ref_clk_hz); if (ddata->hwcaps_mask & CQSPI_SUPPORTS_OCTAL) master->mode_bits |= SPI_RX_OCTAL; if (!(ddata->quirks & CQSPI_DISABLE_DAC_MODE)) cqspi->use_direct_mode = true; } ret = devm_request_irq(dev, irq, cqspi_irq_handler, 0, pdev->name, cqspi); if (ret) { dev_err(dev, "Cannot request IRQ.\n"); goto probe_reset_failed; } cqspi_wait_idle(cqspi); cqspi_controller_init(cqspi); cqspi->current_cs = -1; cqspi->sclk = 0; ret = cqspi_setup_flash(cqspi); if (ret) { dev_err(dev, "failed to setup flash parameters %d\n", ret); goto probe_setup_failed; } if (cqspi->use_direct_mode) { ret = cqspi_request_mmap_dma(cqspi); if (ret == -EPROBE_DEFER) goto probe_setup_failed; } ret = devm_spi_register_master(dev, master); if (ret) { dev_err(&pdev->dev, "failed to register SPI ctlr %d\n", ret); goto probe_setup_failed; } return 0; probe_setup_failed: cqspi_controller_enable(cqspi, 0); probe_reset_failed: clk_disable_unprepare(cqspi->clk); probe_clk_failed: pm_runtime_put_sync(dev); pm_runtime_disable(dev); probe_master_put: spi_master_put(master); return ret; } static int cqspi_remove(struct platform_device *pdev) { struct cqspi_st *cqspi = platform_get_drvdata(pdev); cqspi_controller_enable(cqspi, 0); if (cqspi->rx_chan) dma_release_channel(cqspi->rx_chan); clk_disable_unprepare(cqspi->clk); pm_runtime_put_sync(&pdev->dev); pm_runtime_disable(&pdev->dev); return 0; } #ifdef CONFIG_PM_SLEEP static int cqspi_suspend(struct device *dev) { struct cqspi_st *cqspi = dev_get_drvdata(dev); cqspi_controller_enable(cqspi, 0); return 0; } static int cqspi_resume(struct device *dev) { struct cqspi_st *cqspi = dev_get_drvdata(dev); cqspi_controller_enable(cqspi, 1); return 0; } static const struct dev_pm_ops cqspi__dev_pm_ops = { .suspend = cqspi_suspend, .resume = cqspi_resume, }; #define CQSPI_DEV_PM_OPS (&cqspi__dev_pm_ops) #else #define CQSPI_DEV_PM_OPS NULL #endif static const struct cqspi_driver_platdata cdns_qspi = { .quirks = CQSPI_DISABLE_DAC_MODE, }; static const struct cqspi_driver_platdata k2g_qspi = { .quirks = CQSPI_NEEDS_WR_DELAY, }; static const struct cqspi_driver_platdata am654_ospi = { .hwcaps_mask = CQSPI_SUPPORTS_OCTAL, .quirks = CQSPI_NEEDS_WR_DELAY, }; static const struct of_device_id cqspi_dt_ids[] = { { .compatible = "cdns,qspi-nor", .data = &cdns_qspi, }, { .compatible = "ti,k2g-qspi", .data = &k2g_qspi, }, { .compatible = "ti,am654-ospi", .data = &am654_ospi, }, { /* end of table */ } }; MODULE_DEVICE_TABLE(of, cqspi_dt_ids); static struct platform_driver cqspi_platform_driver = { .probe = cqspi_probe, .remove = cqspi_remove, .driver = { .name = CQSPI_NAME, .pm = CQSPI_DEV_PM_OPS, .of_match_table = cqspi_dt_ids, }, }; module_platform_driver(cqspi_platform_driver); MODULE_DESCRIPTION("Cadence QSPI Controller Driver"); MODULE_LICENSE("GPL v2"); MODULE_ALIAS("platform:" CQSPI_NAME); MODULE_AUTHOR("Ley Foon Tan "); MODULE_AUTHOR("Graham Moore "); MODULE_AUTHOR("Vadivel Murugan R "); MODULE_AUTHOR("Vignesh Raghavendra ");