On Wed, 2015-03-04 at 14:31 -0600, tthayer@xxxxxxxxxxxxxxxxxxxxx wrote:
> From: Thor Thayer <tthayer@xxxxxxxxxxxxxxxxxxxxx>
>
> Altera's Arria10 SoC requires a 32 bit access for peripherals.
> The current spi-dw driver uses 16bit accesses in some locations.
> Use function pointers to support 32 bit accesses and not break
> legacy 16 bit access.
Besides comment to cover letter few more here.
>
> Signed-off-by: Thor Thayer <tthayer@xxxxxxxxxxxxxxxxxxxxx>
> ---
> drivers/spi/spi-dw-mmio.c | 7 ++++++-
> drivers/spi/spi-dw.c | 38 ++++++++++++++++++++++----------------
> drivers/spi/spi-dw.h | 10 ++++++----
> 3 files changed, 34 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/spi/spi-dw-mmio.c b/drivers/spi/spi-dw-mmio.c
> index eb03e12..ee77005 100644
> --- a/drivers/spi/spi-dw-mmio.c
> +++ b/drivers/spi/spi-dw-mmio.c
> @@ -76,8 +76,13 @@ static int dw_spi_mmio_probe(struct platform_device *pdev)
>
> num_cs = 4;
>
> - if (pdev->dev.of_node)
> + if (pdev->dev.of_node) {
> of_property_read_u32(pdev->dev.of_node, "num-cs", &num_cs);
> + if (of_property_read_bool(pdev->dev.of_node, "32bit_access")) {
> + dws->dwread = dw_readl;
> + dws->dwwrite = dw_writel;
> + }
> + }
>
> dws->num_cs = num_cs;
>
> diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c
> index 05af817..614de7f 100644
> --- a/drivers/spi/spi-dw.c
> +++ b/drivers/spi/spi-dw.c
> @@ -149,7 +149,7 @@ static inline u32 tx_max(struct dw_spi *dws)
> u32 tx_left, tx_room, rxtx_gap;
>
> tx_left = (dws->tx_end - dws->tx) / dws->n_bytes;
> - tx_room = dws->fifo_len - dw_readw(dws, DW_SPI_TXFLR);
> + tx_room = dws->fifo_len - dws->dwread(dws, DW_SPI_TXFLR);
>
> /*
> * Another concern is about the tx/rx mismatch, we
> @@ -170,7 +170,7 @@ static inline u32 rx_max(struct dw_spi *dws)
> {
> u32 rx_left = (dws->rx_end - dws->rx) / dws->n_bytes;
>
> - return min_t(u32, rx_left, dw_readw(dws, DW_SPI_RXFLR));
> + return min_t(u32, rx_left, dws->dwread(dws, DW_SPI_RXFLR));
> }
>
> static void dw_writer(struct dw_spi *dws)
> @@ -186,7 +186,7 @@ static void dw_writer(struct dw_spi *dws)
> else
> txw = *(u16 *)(dws->tx);
> }
> - dw_writew(dws, DW_SPI_DR, txw);
> + dws->dwwrite(dws, DW_SPI_DR, txw);
> dws->tx += dws->n_bytes;
> }
> }
> @@ -194,10 +194,10 @@ static void dw_writer(struct dw_spi *dws)
> static void dw_reader(struct dw_spi *dws)
> {
> u32 max = rx_max(dws);
> - u16 rxw;
> + u32 rxw;
>
> while (max--) {
> - rxw = dw_readw(dws, DW_SPI_DR);
> + rxw = dws->dwread(dws, DW_SPI_DR);
> /* Care rx only if the transfer's original "rx" is not null */
> if (dws->rx_end - dws->len) {
> if (dws->n_bytes == 1)
> @@ -299,13 +299,13 @@ EXPORT_SYMBOL_GPL(dw_spi_xfer_done);
>
> static irqreturn_t interrupt_transfer(struct dw_spi *dws)
> {
> - u16 irq_status = dw_readw(dws, DW_SPI_ISR);
> + u32 irq_status = dws->dwread(dws, DW_SPI_ISR);
>
> /* Error handling */
> if (irq_status & (SPI_INT_TXOI | SPI_INT_RXOI | SPI_INT_RXUI)) {
> - dw_readw(dws, DW_SPI_TXOICR);
> - dw_readw(dws, DW_SPI_RXOICR);
> - dw_readw(dws, DW_SPI_RXUICR);
> + dws->dwread(dws, DW_SPI_TXOICR);
> + dws->dwread(dws, DW_SPI_RXOICR);
> + dws->dwread(dws, DW_SPI_RXUICR);
Better to issue separate patch first which substitutes those 3 by 1
dw_readw(dws, DW_SPI_ICR);
> int_error_stop(dws, "interrupt_transfer: fifo overrun/underrun");
> return IRQ_HANDLED;
> }
> @@ -329,7 +329,7 @@ static irqreturn_t interrupt_transfer(struct dw_spi *dws)
> static irqreturn_t dw_spi_irq(int irq, void *dev_id)
> {
> struct dw_spi *dws = dev_id;
> - u16 irq_status = dw_readw(dws, DW_SPI_ISR) & 0x3f;
> + u32 irq_status = dws->dwread(dws, DW_SPI_ISR) & 0x3f;
>
> if (!irq_status)
> return IRQ_NONE;
> @@ -473,10 +473,11 @@ static void pump_transfers(unsigned long data)
> * 2. clk_div is changed
> * 3. control value changes
> */
> - if (dw_readw(dws, DW_SPI_CTRL0) != cr0 || cs_change || clk_div || imask) {
> + if (dws->dwread(dws, DW_SPI_CTRL0) != cr0 ||
> + cs_change || clk_div || imask) {
> spi_enable_chip(dws, 0);
>
> - dw_writew(dws, DW_SPI_CTRL0, cr0);
> + dws->dwwrite(dws, DW_SPI_CTRL0, cr0);
>
> spi_set_clk(dws, chip->clk_div);
> spi_chip_sel(dws, spi, 1);
If possible, can you re-base on top of my patchset an re-test?
http://www.spinics.net/lists/linux-spi/msg03004.html
> @@ -486,7 +487,7 @@ static void pump_transfers(unsigned long data)
> if (imask)
> spi_umask_intr(dws, imask);
> if (txlevel)
> - dw_writew(dws, DW_SPI_TXFLTR, txlevel);
> + dws->dwwrite(dws, DW_SPI_TXFLTR, txlevel);
>
> spi_enable_chip(dws, 1);
> }
> @@ -618,11 +619,11 @@ static void spi_hw_init(struct device *dev, struct dw_spi *dws)
> u32 fifo;
>
> for (fifo = 1; fifo < 256; fifo++) {
> - dw_writew(dws, DW_SPI_TXFLTR, fifo);
> - if (fifo != dw_readw(dws, DW_SPI_TXFLTR))
> + dws->dwwrite(dws, DW_SPI_TXFLTR, fifo);
> + if (fifo != dws->dwread(dws, DW_SPI_TXFLTR))
> break;
> }
> - dw_writew(dws, DW_SPI_TXFLTR, 0);
> + dws->dwwrite(dws, DW_SPI_TXFLTR, 0);
>
> dws->fifo_len = (fifo == 1) ? 0 : fifo;
> dev_dbg(dev, "Detected FIFO size: %u bytes\n", dws->fifo_len);
> @@ -647,6 +648,11 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws)
> dws->dma_addr = (dma_addr_t)(dws->paddr + 0x60);
> snprintf(dws->name, sizeof(dws->name), "dw_spi%d", dws->bus_num);
>
> + if (!dws->dwread)
> + dws->dwread = dw_readw;
> + if (!dws->dwwrite)
> + dws->dwwrite = dw_writew;
> +
> ret = devm_request_irq(dev, dws->irq, dw_spi_irq, IRQF_SHARED,
> dws->name, dws);
> if (ret < 0) {
> diff --git a/drivers/spi/spi-dw.h b/drivers/spi/spi-dw.h
> index 3d32be6..5ca2407 100644
> --- a/drivers/spi/spi-dw.h
> +++ b/drivers/spi/spi-dw.h
> @@ -150,6 +150,8 @@ struct dw_spi {
> #ifdef CONFIG_DEBUG_FS
> struct dentry *debugfs;
> #endif
> + u32 (*dwread)(struct dw_spi *dws, u32 offset);
> + void (*dwwrite)(struct dw_spi *dws, u32 offset, u16 val);
u16?!
> };
>
> static inline u32 dw_readl(struct dw_spi *dws, u32 offset)
> @@ -157,14 +159,14 @@ 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)
> +static inline void dw_writel(struct dw_spi *dws, u32 offset, u16 val)
So, why u16?
> {
> - __raw_writel(val, dws->regs + offset);
> + __raw_writel((u32)val, dws->regs + offset);
Seems like a mess here. Could you figure out, please, what should be
done?
> }
>
> -static inline u16 dw_readw(struct dw_spi *dws, u32 offset)
> +static inline u32 dw_readw(struct dw_spi *dws, u32 offset)
> {
> - return __raw_readw(dws->regs + offset);
> + return (u32)__raw_readw(dws->regs + offset);
why readw?
> }
>
> static inline void dw_writew(struct dw_spi *dws, u32 offset, u16 val)
We have exactly 4 functions. What is wrong to use proper ones?
So, I would appreciate to hear an answer to the question in cover letter
reply and if you reorganizes code to use proper functions.
--
Andy Shevchenko <andriy.shevchenko@xxxxxxxxx>
Intel Finland Oy
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