tty: amba-pl011: use iotype instead of access_32b to track 32-bit I/O

Instead of defining a new field in the uart_amba_port structure, use the
existing iotype field of the uart_port structure, which is intended for
this purpose.  If we need to use 32-bit register access, we set iotype
to UPIO_MEM32, otherwise we set it to UPIO_MEM.

For early console, specify the "mmio32" option on the kernel command-line.
Example:

        earlycon=pl011,mmio32,0x3ced1000

Signed-off-by: Timur Tabi <timur@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 054e11d33b6b01ed68dcfb21901cae21d2289948..654c547b9fc9955297739214950fffb910c23154 100644 (file)
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1003,10 +1003,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        unspecified, the h/w is not initialized.
 
                pl011,<addr>
+               pl011,mmio32,<addr>
                        Start an early, polled-mode console on a pl011 serial
                        port at the specified address. The pl011 serial port
                        must already be setup and configured. Options are not
-                       yet supported.
+                       yet supported.  If 'mmio32' is specified, then only
+                       the driver will use only 32-bit accessors to read/write
+                       the device registers.
 
                msm_serial,<addr>
                        Start an early, polled-mode console on an msm serial

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index a7d7ab05dc649e67315de9e4c47797641049e45e..c0da0ccbbcf5476575c9b5f1c06cbb4827056ce4 100644 (file)
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -238,7 +238,6 @@ struct uart_amba_port {
        unsigned int            fifosize;       /* vendor-specific */
        unsigned int            old_cr;         /* state during shutdown */
        bool                    autorts;
-       bool                    access_32b;
        unsigned int            fixed_baud;     /* vendor-set fixed baud rate */
        char                    type[12];
 #ifdef CONFIG_DMA_ENGINE
@@ -262,7 +261,8 @@ static unsigned int pl011_read(const struct uart_amba_port *uap,
 {
        void __iomem *addr = uap->port.membase + pl011_reg_to_offset(uap, reg);
 
-       return uap->access_32b ? readl_relaxed(addr) : readw_relaxed(addr);
+       return (uap->port.iotype == UPIO_MEM32) ?
+               readl_relaxed(addr) : readw_relaxed(addr);
 }
 
 static void pl011_write(unsigned int val, const struct uart_amba_port *uap,
@@ -270,7 +270,7 @@ static void pl011_write(unsigned int val, const struct uart_amba_port *uap,
 {
        void __iomem *addr = uap->port.membase + pl011_reg_to_offset(uap, reg);
 
-       if (uap->access_32b)
+       if (uap->port.iotype == UPIO_MEM32)
                writel_relaxed(val, addr);
        else
                writew_relaxed(val, addr);
@@ -2303,7 +2303,10 @@ static void pl011_putc(struct uart_port *port, int c)
 {
        while (readl(port->membase + UART01x_FR) & UART01x_FR_TXFF)
                ;
-       writeb(c, port->membase + UART01x_DR);
+       if (port->iotype == UPIO_MEM32)
+               writel(c, port->membase + UART01x_DR);
+       else
+               writeb(c, port->membase + UART01x_DR);
        while (readl(port->membase + UART01x_FR) & UART01x_FR_BUSY)
                ;
 }
@@ -2416,7 +2419,6 @@ static int pl011_setup_port(struct device *dev, struct uart_amba_port *uap,
        uap->port.dev = dev;
        uap->port.mapbase = mmiobase->start;
        uap->port.membase = base;
-       uap->port.iotype = UPIO_MEM;
        uap->port.fifosize = uap->fifosize;
        uap->port.flags = UPF_BOOT_AUTOCONF;
        uap->port.line = index;
@@ -2470,9 +2472,9 @@ static int pl011_probe(struct amba_device *dev, const struct amba_id *id)
                return PTR_ERR(uap->clk);
 
        uap->reg_offset = vendor->reg_offset;
-       uap->access_32b = vendor->access_32b;
        uap->vendor = vendor;
        uap->fifosize = vendor->get_fifosize(dev);
+       uap->port.iotype = vendor->access_32b ? UPIO_MEM32 : UPIO_MEM;
        uap->port.irq = dev->irq[0];
        uap->port.ops = &amba_pl011_pops;
 
@@ -2551,9 +2553,9 @@ static int sbsa_uart_probe(struct platform_device *pdev)
                return -ENOMEM;
 
        uap->reg_offset = vendor_sbsa.reg_offset;
-       uap->access_32b = vendor_sbsa.access_32b;
        uap->vendor     = &vendor_sbsa;
        uap->fifosize   = 32;
+       uap->port.iotype = vendor_sbsa.access_32b ? UPIO_MEM32 : UPIO_MEM;
        uap->port.irq   = platform_get_irq(pdev, 0);
        uap->port.ops   = &sbsa_uart_pops;
        uap->fixed_baud = baudrate;