diff mbox series

serial: uartlite: Add support to work with any endianness

Message ID 113756fda74a683fe15728fabdf96f0599750172.1598530214.git.michal.simek@xilinx.com
State Deferred
Delegated to: Tom Rini
Headers show
Series serial: uartlite: Add support to work with any endianness | expand

Commit Message

Michal Simek Aug. 27, 2020, 12:10 p.m. UTC 
From: T Karthik Reddy <t.karthik.reddy@xilinx.com>

This endinness changes are taken from linux uartlite driver.
Reset TX fifo in control register and check TX fifo empty
flag in lower byte of the status register to detect if it
is a little endian system. Based on this check, program the
registers with le32 or be32 through out the driver.

Signed-off-by: T Karthik Reddy <t.karthik.reddy@xilinx.com>
Signed-off-by: Ashok Reddy Soma <ashok.reddy.soma@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
---

 drivers/serial/serial_xuartlite.c | 74 ++++++++++++++++++++++++++-----
 1 file changed, 64 insertions(+), 10 deletions(-)

Comments

Michal Simek Sept. 14, 2020, 9:25 a.m. UTC | #1 
Hi,

čt 27. 8. 2020 v 14:10 odesílatel Michal Simek <michal.simek@xilinx.com> napsal:
>
> From: T Karthik Reddy <t.karthik.reddy@xilinx.com>
>
> This endinness changes are taken from linux uartlite driver.
> Reset TX fifo in control register and check TX fifo empty
> flag in lower byte of the status register to detect if it
> is a little endian system. Based on this check, program the
> registers with le32 or be32 through out the driver.
>
> Signed-off-by: T Karthik Reddy <t.karthik.reddy@xilinx.com>
> Signed-off-by: Ashok Reddy Soma <ashok.reddy.soma@xilinx.com>
> Signed-off-by: Michal Simek <michal.simek@xilinx.com>
> ---
>
>  drivers/serial/serial_xuartlite.c | 74 ++++++++++++++++++++++++++-----
>  1 file changed, 64 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/serial/serial_xuartlite.c b/drivers/serial/serial_xuartlite.c
> index 5116d13751de..e16642504b16 100644
> --- a/drivers/serial/serial_xuartlite.c
> +++ b/drivers/serial/serial_xuartlite.c
> @@ -32,17 +32,64 @@ struct uartlite {
>
>  struct uartlite_platdata {
>         struct uartlite *regs;
> +       const struct uartlite_reg_ops *reg_ops;
>  };
>
> +struct uartlite_reg_ops {
> +       u32 (*in)(void __iomem *addr);
> +       void (*out)(u32 val, void __iomem *addr);
> +};
> +
> +static u32 uartlite_inle32(void __iomem *addr)
> +{
> +       return in_le32(addr);
> +}
> +
> +static void uartlite_outle32(u32 val, void __iomem *addr)
> +{
> +       out_le32(addr, val);
> +}
> +
> +static const struct uartlite_reg_ops uartlite_le = {
> +       .in = uartlite_inle32,
> +       .out = uartlite_outle32,
> +};
> +
> +static u32 uartlite_inbe32(void __iomem *addr)
> +{
> +       return in_be32(addr);
> +}
> +
> +static void uartlite_outbe32(u32 val, void __iomem *addr)
> +{
> +       out_be32(addr, val);
> +}
> +
> +static const struct uartlite_reg_ops uartlite_be = {
> +       .in = uartlite_inbe32,
> +       .out = uartlite_outbe32,
> +};
> +
> +static u32 uart_in32(void __iomem *addr, struct uartlite_platdata *plat)
> +{
> +       return plat->reg_ops->in(addr);
> +}
> +
> +static void uart_out32(void __iomem *addr, u32 val,
> +                      struct uartlite_platdata *plat)
> +{
> +       plat->reg_ops->out(val, addr);
> +}
> +
>  static int uartlite_serial_putc(struct udevice *dev, const char ch)
>  {
>         struct uartlite_platdata *plat = dev_get_platdata(dev);
>         struct uartlite *regs = plat->regs;
>
> -       if (in_be32(&regs->status) & SR_TX_FIFO_FULL)
> +       if (uart_in32(&regs->status, plat) & SR_TX_FIFO_FULL)
>                 return -EAGAIN;
>
> -       out_be32(&regs->tx_fifo, ch & 0xff);
> +       uart_out32(&regs->tx_fifo, ch & 0xff, plat);
>
>         return 0;
>  }
> @@ -52,10 +99,10 @@ static int uartlite_serial_getc(struct udevice *dev)
>         struct uartlite_platdata *plat = dev_get_platdata(dev);
>         struct uartlite *regs = plat->regs;
>
> -       if (!(in_be32(&regs->status) & SR_RX_FIFO_VALID_DATA))
> +       if (!(uart_in32(&regs->status, plat) & SR_RX_FIFO_VALID_DATA))
>                 return -EAGAIN;
>
> -       return in_be32(&regs->rx_fifo) & 0xff;
> +       return uart_in32(&regs->rx_fifo, plat) & 0xff;
>  }
>
>  static int uartlite_serial_pending(struct udevice *dev, bool input)
> @@ -64,19 +111,26 @@ static int uartlite_serial_pending(struct udevice *dev, bool input)
>         struct uartlite *regs = plat->regs;
>
>         if (input)
> -               return in_be32(&regs->status) & SR_RX_FIFO_VALID_DATA;
> +               return uart_in32(&regs->status, plat) & SR_RX_FIFO_VALID_DATA;
>
> -       return !(in_be32(&regs->status) & SR_TX_FIFO_EMPTY);
> +       return !(uart_in32(&regs->status, plat) & SR_TX_FIFO_EMPTY);
>  }
>
>  static int uartlite_serial_probe(struct udevice *dev)
>  {
>         struct uartlite_platdata *plat = dev_get_platdata(dev);
>         struct uartlite *regs = plat->regs;
> -
> -       out_be32(&regs->control, 0);
> -       out_be32(&regs->control, ULITE_CONTROL_RST_RX | ULITE_CONTROL_RST_TX);
> -       in_be32(&regs->control);
> +       int ret;
> +
> +       plat->reg_ops = &uartlite_be;
> +       ret = uart_in32(&regs->control, plat);
> +       uart_out32(&regs->control, 0, plat);
> +       uart_out32(&regs->control,
> +                  ULITE_CONTROL_RST_RX | ULITE_CONTROL_RST_TX, plat);
> +       ret = uart_in32(&regs->status, plat);
> +       /* Endianness detection */
> +       if ((ret & SR_TX_FIFO_EMPTY) != SR_TX_FIFO_EMPTY)
> +               plat->reg_ops = &uartlite_le;
>
>         return 0;
>  }
> --
> 2.28.0
>

We found some issues with this patch that's why please ignore it - v2
will be sent.

Thanks,
Michal
diff mbox series

Patch

diff --git a/drivers/serial/serial_xuartlite.c b/drivers/serial/serial_xuartlite.c
index 5116d13751de..e16642504b16 100644
--- a/drivers/serial/serial_xuartlite.c
+++ b/drivers/serial/serial_xuartlite.c
@@ -32,17 +32,64 @@  struct uartlite {
 
 struct uartlite_platdata {
 	struct uartlite *regs;
+	const struct uartlite_reg_ops *reg_ops;
 };
 
+struct uartlite_reg_ops {
+	u32 (*in)(void __iomem *addr);
+	void (*out)(u32 val, void __iomem *addr);
+};
+
+static u32 uartlite_inle32(void __iomem *addr)
+{
+	return in_le32(addr);
+}
+
+static void uartlite_outle32(u32 val, void __iomem *addr)
+{
+	out_le32(addr, val);
+}
+
+static const struct uartlite_reg_ops uartlite_le = {
+	.in = uartlite_inle32,
+	.out = uartlite_outle32,
+};
+
+static u32 uartlite_inbe32(void __iomem *addr)
+{
+	return in_be32(addr);
+}
+
+static void uartlite_outbe32(u32 val, void __iomem *addr)
+{
+	out_be32(addr, val);
+}
+
+static const struct uartlite_reg_ops uartlite_be = {
+	.in = uartlite_inbe32,
+	.out = uartlite_outbe32,
+};
+
+static u32 uart_in32(void __iomem *addr, struct uartlite_platdata *plat)
+{
+	return plat->reg_ops->in(addr);
+}
+
+static void uart_out32(void __iomem *addr, u32 val,
+		       struct uartlite_platdata *plat)
+{
+	plat->reg_ops->out(val, addr);
+}
+
 static int uartlite_serial_putc(struct udevice *dev, const char ch)
 {
 	struct uartlite_platdata *plat = dev_get_platdata(dev);
 	struct uartlite *regs = plat->regs;
 
-	if (in_be32(&regs->status) & SR_TX_FIFO_FULL)
+	if (uart_in32(&regs->status, plat) & SR_TX_FIFO_FULL)
 		return -EAGAIN;
 
-	out_be32(&regs->tx_fifo, ch & 0xff);
+	uart_out32(&regs->tx_fifo, ch & 0xff, plat);
 
 	return 0;
 }
@@ -52,10 +99,10 @@  static int uartlite_serial_getc(struct udevice *dev)
 	struct uartlite_platdata *plat = dev_get_platdata(dev);
 	struct uartlite *regs = plat->regs;
 
-	if (!(in_be32(&regs->status) & SR_RX_FIFO_VALID_DATA))
+	if (!(uart_in32(&regs->status, plat) & SR_RX_FIFO_VALID_DATA))
 		return -EAGAIN;
 
-	return in_be32(&regs->rx_fifo) & 0xff;
+	return uart_in32(&regs->rx_fifo, plat) & 0xff;
 }
 
 static int uartlite_serial_pending(struct udevice *dev, bool input)
@@ -64,19 +111,26 @@  static int uartlite_serial_pending(struct udevice *dev, bool input)
 	struct uartlite *regs = plat->regs;
 
 	if (input)
-		return in_be32(&regs->status) & SR_RX_FIFO_VALID_DATA;
+		return uart_in32(&regs->status, plat) & SR_RX_FIFO_VALID_DATA;
 
-	return !(in_be32(&regs->status) & SR_TX_FIFO_EMPTY);
+	return !(uart_in32(&regs->status, plat) & SR_TX_FIFO_EMPTY);
 }
 
 static int uartlite_serial_probe(struct udevice *dev)
 {
 	struct uartlite_platdata *plat = dev_get_platdata(dev);
 	struct uartlite *regs = plat->regs;
-
-	out_be32(&regs->control, 0);
-	out_be32(&regs->control, ULITE_CONTROL_RST_RX | ULITE_CONTROL_RST_TX);
-	in_be32(&regs->control);
+	int ret;
+
+	plat->reg_ops = &uartlite_be;
+	ret = uart_in32(&regs->control, plat);
+	uart_out32(&regs->control, 0, plat);
+	uart_out32(&regs->control,
+		   ULITE_CONTROL_RST_RX | ULITE_CONTROL_RST_TX, plat);
+	ret = uart_in32(&regs->status, plat);
+	/* Endianness detection */
+	if ((ret & SR_TX_FIFO_EMPTY) != SR_TX_FIFO_EMPTY)
+		plat->reg_ops = &uartlite_le;
 
 	return 0;
 }