Hugo Villeneuve <[email protected]> writes:
> This bug occurs when the davinci serial code tries to register UART(X) when
> UART(X-1) or UART(X-2) is not enabled in the structure uart_config of the
> board
> setup code:
>
> This works: .enabled_uarts = (1 << 0)
> This works: .enabled_uarts = (1 << 0) | (1 << 1)
> This works: .enabled_uarts = (1 << 0) | (1 << 1) | | (1 << 2)
> This fails: .enabled_uarts = (1 << 1)
> This fails: .enabled_uarts = (1 << 1) | (1 << 2)
> This fails: .enabled_uarts = (1 << 0) | (1 << 2)
>
> The bug is triggered by the fact that the 8250 serial driver stops parsing the
> serial_platform_data structure as soon as it sees a zero flags entry. Thus the
> davinci serial registration code (serial.c) must <pack> the
> serial_platform_data
> structure and only clear the flags entry when there is no more devices
> following.
>
> Tested on DM6446 and DM355 custom boards.
>
> Signed-off-by: Hugo Villeneuve <[email protected]>
Thanks, pushing today.
Kevin
> ---
> arch/arm/mach-davinci/serial.c | 81
> +++++++++++++++++++---------------------
> 1 files changed, 38 insertions(+), 43 deletions(-)
>
> diff --git a/arch/arm/mach-davinci/serial.c b/arch/arm/mach-davinci/serial.c
> index 95c71b9..99102ac 100644
> --- a/arch/arm/mach-davinci/serial.c
> +++ b/arch/arm/mach-davinci/serial.c
> @@ -49,36 +49,24 @@ static inline void serial_write_reg(struct
> plat_serial8250_port *p, int offset,
> __raw_writel(value, IO_ADDRESS(p->mapbase) + offset);
> }
>
> -static struct plat_serial8250_port serial_platform_data[] = {
> - {
> - .mapbase = DAVINCI_UART0_BASE,
> - .irq = IRQ_UARTINT0,
> - .flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST |
> - UPF_IOREMAP,
> - .iotype = UPIO_MEM,
> - .regshift = 2,
> - },
> - {
> - .mapbase = DAVINCI_UART1_BASE,
> - .irq = IRQ_UARTINT1,
> - .flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST |
> - UPF_IOREMAP,
> - .iotype = UPIO_MEM,
> - .regshift = 2,
> - },
> - {
> - .mapbase = DAVINCI_UART2_BASE,
> - .irq = IRQ_UARTINT2,
> - .flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST |
> - UPF_IOREMAP,
> - .iotype = UPIO_MEM,
> - .regshift = 2,
> - },
> - {
> - .flags = 0
> - },
> +static const resource_size_t serial_mapbase[] = {
> + DAVINCI_UART0_BASE,
> + DAVINCI_UART1_BASE,
> + DAVINCI_UART2_BASE,
> };
>
> +static const unsigned int serial_irq[] = {
> + IRQ_UARTINT0,
> + IRQ_UARTINT1,
> + IRQ_UARTINT2,
> +};
> +
> +/*
> + * The additional entry is present because the list must be terminated with a
> + * zero flags entry.
> + */
> +static struct plat_serial8250_port serial_platform_data[DAVINCI_MAX_NR_UARTS
> + 1];
> +
> static struct platform_device serial_device = {
> .name = "serial8250",
> .id = PLAT8250_DEV_PLATFORM,
> @@ -112,29 +100,31 @@ void __init davinci_serial_init(struct
> davinci_uart_config *info)
> char name[16];
> struct clk *uart_clk;
> struct device *dev = &serial_device.dev;
> + struct plat_serial8250_port *p = serial_platform_data;
>
> /*
> * Make sure the serial ports are muxed on at this point.
> - * You have to mux them off in device drivers later on
> - * if not needed.
> + * You have to mux them off in device drivers later on if not needed.
> */
> for (i = 0; i < DAVINCI_MAX_NR_UARTS; i++) {
> - struct plat_serial8250_port *p = serial_platform_data + i;
> -
> - if (!(info->enabled_uarts & (1 << i))) {
> - p->flags = 0;
> + if (!(info->enabled_uarts & (1 << i)))
> continue;
> - }
>
> - if (cpu_is_davinci_dm646x()) {
> - p->iotype = UPIO_MEM32;
> - }
> + /* fill-in common members */
> + p->flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST | UPF_IOREMAP;
> + p->regshift = 2;
>
> - if (cpu_is_davinci_dm355()) {
> - if (i == 2) {
> - p->mapbase = (unsigned long)DM355_UART2_BASE;
> - p->irq = IRQ_DM355_UARTINT2;
> - }
> + if (cpu_is_davinci_dm646x())
> + p->iotype = UPIO_MEM32;
> + else
> + p->iotype = UPIO_MEM;
> +
> + if (cpu_is_davinci_dm355() && (i == 2)) {
> + p->mapbase = DM355_UART2_BASE;
> + p->irq = IRQ_DM355_UARTINT2;
> + } else {
> + p->mapbase = serial_mapbase[i];
> + p->irq = serial_irq[i];
> }
>
> sprintf(name, "uart%d", i);
> @@ -147,7 +137,12 @@ void __init davinci_serial_init(struct
> davinci_uart_config *info)
> clk_enable(uart_clk);
> davinci_serial_reset(p);
> }
> +
> + p++; /* Point to next entry */
> }
> +
> + /* Terminate the list with a zero flags entry */
> + p->flags = 0;
> }
>
> static int __init davinci_init(void)
> --
> 1.5.4.5
>
>
> _______________________________________________
> Davinci-linux-open-source mailing list
> [email protected]
> http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
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