Re: [PATCH] aspeed: Refactor UART init for multi-SoC machines

[Peter Delevoryas]

On Fri, Jul 01, 2022 at 12:56:19PM -0700, Peter Delevoryas wrote:
> This change moves the code that connects the SoC UART's to serial_hd's
> to the machine.
> 
> It makes each UART a proper child member of the SoC, and then allows the
> machine to selectively initialize the chardev for each UART with a
> serial_hd.
> 
> This should preserve backwards compatibility, but also allow multi-SoC
> boards to completely change the wiring of serial devices from the
> command line to specific SoC UART's.
> 
> This also removes the uart-default property from the SoC, since the SoC
> doesn't need to know what UART is the "default" on the machine anymore.
> 
> I tested this using the images and commands from the previous
> refactoring, and another test image for the ast1030:
> 
>     wget 
> https://github.com/facebook/openbmc/releases/download/v2021.49.0/fuji.mtd
>     wget 
> https://github.com/facebook/openbmc/releases/download/v2021.49.0/wedge100.mtd
>     wget 
> https://github.com/peterdelevoryas/OpenBIC/releases/download/oby35-cl-2022.13.01/Y35BCL.elf
> 
> Fuji uses UART1:
> 
>     qemu-system-arm -machine fuji-bmc \
>         -drive file=fuji.mtd,format=raw,if=mtd \
>         -nographic
> 
> ast2600-evb uses uart-default=UART5:
> 
>     qemu-system-arm -machine ast2600-evb \
>         -drive file=fuji.mtd,format=raw,if=mtd \
>         -serial null -serial mon:stdio -display none
> 
> Wedge100 uses UART3:
> 
>     qemu-system-arm -machine palmetto-bmc \
>         -drive file=wedge100.mtd,format=raw,if=mtd \
>         -serial null -serial null -serial null \
>         -serial mon:stdio -display none
> 
> AST1030 EVB uses UART5:
> 
>     qemu-system-arm -machine ast1030-evb \
>         -kernel Y35BCL.elf -nographic
> 
> Fixes: 6827ff20b2975 ("hw: aspeed: Init all UART's with serial devices")
> Signed-off-by: Peter Delevoryas <me@pjd.dev>
> ---
>  hw/arm/aspeed.c             | 23 +++++++++++++++----
>  hw/arm/aspeed_ast10x0.c     |  4 ++++
>  hw/arm/aspeed_ast2600.c     |  4 ++++
>  hw/arm/aspeed_soc.c         | 44 ++++++++++++++++++++++++-------------
>  include/hw/arm/aspeed_soc.h |  4 ++++
>  5 files changed, 60 insertions(+), 19 deletions(-)
> 
> diff --git a/hw/arm/aspeed.c b/hw/arm/aspeed.c
> index 6fe9b13548..fdca0abd95 100644
> --- a/hw/arm/aspeed.c
> +++ b/hw/arm/aspeed.c
> @@ -26,6 +26,7 @@
>  #include "qemu/error-report.h"
>  #include "qemu/units.h"
>  #include "hw/qdev-clock.h"
> +#include "sysemu/sysemu.h"
>  
>  static struct arm_boot_info aspeed_board_binfo = {
>      .board_id = -1, /* device-tree-only board */
> @@ -301,6 +302,22 @@ static void sdhci_attach_drive(SDHCIState *sdhci, 
> DriveInfo *dinfo)
>                                 &error_fatal);
>  }
>  
> +static void connect_serial_hds_to_uarts(AspeedMachineState *bmc)
> +{
> +    AspeedMachineClass *amc = ASPEED_MACHINE_GET_CLASS(bmc);
> +    AspeedSoCState *s = &bmc->soc;
> +
> +    aspeed_soc_uart_set_chr(s, amc->uart_default, serial_hd(0));
> +    for (int i = 1, uart = ASPEED_DEV_UART1;
> +         serial_hd(i) && uart <= ASPEED_DEV_UART13; i++, uart++) {
> +
> +        if (uart == amc->uart_default) {
> +            continue;
> +        }
> +        aspeed_soc_uart_set_chr(s, uart, serial_hd(i));
> +    }
> +}
> +
>  static void aspeed_machine_init(MachineState *machine)
>  {
>      AspeedMachineState *bmc = ASPEED_MACHINE(machine);
> @@ -346,8 +363,7 @@ static void aspeed_machine_init(MachineState *machine)
>          object_property_set_int(OBJECT(&bmc->soc), "hw-prot-key",
>                                  ASPEED_SCU_PROT_KEY, &error_abort);
>      }
> -    qdev_prop_set_uint32(DEVICE(&bmc->soc), "uart-default",
> -                         amc->uart_default);
> +    connect_serial_hds_to_uarts(bmc);
>      qdev_realize(DEVICE(&bmc->soc), NULL, &error_abort);
>  
>      aspeed_board_init_flashes(&bmc->soc.fmc,
> @@ -1383,8 +1399,7 @@ static void aspeed_minibmc_machine_init(MachineState 
> *machine)
>  
>      object_property_set_link(OBJECT(&bmc->soc), "memory",
>                               OBJECT(get_system_memory()), &error_abort);
> -    qdev_prop_set_uint32(DEVICE(&bmc->soc), "uart-default",
> -                         amc->uart_default);
> +    connect_serial_hds_to_uarts(bmc);
>      qdev_realize(DEVICE(&bmc->soc), NULL, &error_abort);
>  
>      aspeed_board_init_flashes(&bmc->soc.fmc,
> diff --git a/hw/arm/aspeed_ast10x0.c b/hw/arm/aspeed_ast10x0.c
> index 33ef331771..a221f5d6fe 100644
> --- a/hw/arm/aspeed_ast10x0.c
> +++ b/hw/arm/aspeed_ast10x0.c
> @@ -144,6 +144,10 @@ static void aspeed_soc_ast1030_init(Object *obj)
>          object_initialize_child(obj, "wdt[*]", &s->wdt[i], typename);
>      }
>  
> +    for (i = 0; i < sc->uarts_num; i++) {
> +        object_initialize_child(obj, "uart[*]", &s->uart[i], TYPE_SERIAL_MM);
> +    }
> +
>      snprintf(typename, sizeof(typename), "aspeed.gpio-%s", socname);
>      object_initialize_child(obj, "gpio", &s->gpio, typename);
>  
> diff --git a/hw/arm/aspeed_ast2600.c b/hw/arm/aspeed_ast2600.c
> index 3f0611ac11..c4ad26a046 100644
> --- a/hw/arm/aspeed_ast2600.c
> +++ b/hw/arm/aspeed_ast2600.c
> @@ -214,6 +214,10 @@ static void aspeed_soc_ast2600_init(Object *obj)
>          object_initialize_child(obj, "mii[*]", &s->mii[i], TYPE_ASPEED_MII);
>      }
>  
> +    for (i = 0; i < sc->uarts_num; i++) {
> +        object_initialize_child(obj, "uart[*]", &s->uart[i], TYPE_SERIAL_MM);
> +    }
> +
>      snprintf(typename, sizeof(typename), TYPE_ASPEED_XDMA "-%s", socname);
>      object_initialize_child(obj, "xdma", &s->xdma, typename);
>  
> diff --git a/hw/arm/aspeed_soc.c b/hw/arm/aspeed_soc.c
> index 0f675e7fcd..2ac18cbf27 100644
> --- a/hw/arm/aspeed_soc.c
> +++ b/hw/arm/aspeed_soc.c
> @@ -208,6 +208,10 @@ static void aspeed_soc_init(Object *obj)
>                                  TYPE_FTGMAC100);
>      }
>  
> +    for (i = 0; i < sc->uarts_num; i++) {
> +        object_initialize_child(obj, "uart[*]", &s->uart[i], TYPE_SERIAL_MM);
> +    }
> +
>      snprintf(typename, sizeof(typename), TYPE_ASPEED_XDMA "-%s", socname);
>      object_initialize_child(obj, "xdma", &s->xdma, typename);
>  
> @@ -481,8 +485,6 @@ static Property aspeed_soc_properties[] = {
>                       MemoryRegion *),
>      DEFINE_PROP_LINK("dram", AspeedSoCState, dram_mr, TYPE_MEMORY_REGION,
>                       MemoryRegion *),
> -    DEFINE_PROP_UINT32("uart-default", AspeedSoCState, uart_default,
> -                       ASPEED_DEV_UART5),
>      DEFINE_PROP_END_OF_LIST(),
>  };
>  
> @@ -575,22 +577,34 @@ qemu_irq aspeed_soc_get_irq(AspeedSoCState *s, int dev)
>  void aspeed_soc_uart_init(AspeedSoCState *s)
>  {
>      AspeedSoCClass *sc = ASPEED_SOC_GET_CLASS(s);
> -    int i, uart;
> -
> -    /* Attach an 8250 to the IO space as our UART */
> -    serial_mm_init(s->memory, sc->memmap[s->uart_default], 2,
> -                   aspeed_soc_get_irq(s, s->uart_default), 38400,
> -                   serial_hd(0), DEVICE_LITTLE_ENDIAN);
> -    for (i = 1, uart = ASPEED_DEV_UART1; i < sc->uarts_num; i++, uart++) {
> -        if (uart == s->uart_default) {
> -            uart++;
> -        }
> -        serial_mm_init(s->memory, sc->memmap[uart], 2,
> -                       aspeed_soc_get_irq(s, uart), 38400,
> -                       serial_hd(i), DEVICE_LITTLE_ENDIAN);
> +    SerialMM *smm;
> +    MemoryRegion *mr;
> +
> +    for (int i = 0, uart = ASPEED_DEV_UART1; i < sc->uarts_num; i++, uart++) 
> {
> +        smm = &s->uart[i];
> +
> +        /* Chardev property is set by the machine. */
> +        qdev_prop_set_uint8(DEVICE(smm), "regshift", 2);
> +        qdev_prop_set_uint32(DEVICE(smm), "baudbase", 38400);
> +        qdev_set_legacy_instance_id(DEVICE(smm), sc->memmap[uart], 2);
> +        qdev_prop_set_uint8(DEVICE(smm), "endianness", DEVICE_LITTLE_ENDIAN);
> +        sysbus_realize(SYS_BUS_DEVICE(smm), &error_fatal);
> +
> +        sysbus_connect_irq(SYS_BUS_DEVICE(smm), 0, aspeed_soc_get_irq(s, 
> uart));
> +        mr = sysbus_mmio_get_region(SYS_BUS_DEVICE(smm), 0);
> +        memory_region_add_subregion(s->memory, sc->memmap[uart], mr);
>      }
>  }
>  
> +void aspeed_soc_uart_set_chr(AspeedSoCState *s, int dev, Chardev *chr)
> +{
> +    AspeedSoCClass *sc = ASPEED_SOC_GET_CLASS(s);
> +    int i = dev - ASPEED_DEV_UART1;
> +
> +    g_assert(0 <= i && i < ARRAY_SIZE(s->uart) && i < sc->uarts_num);
> +    qdev_prop_set_chr(DEVICE(&s->uart[i]), "chardev", chr);
> +}
> +
>  /*
>   * SDMC should be realized first to get correct RAM size and max size
>   * values
> diff --git a/include/hw/arm/aspeed_soc.h b/include/hw/arm/aspeed_soc.h
> index e65926a667..06c9ab20f8 100644
> --- a/include/hw/arm/aspeed_soc.h
> +++ b/include/hw/arm/aspeed_soc.h
> @@ -36,12 +36,14 @@
>  #include "hw/misc/aspeed_lpc.h"
>  #include "hw/misc/unimp.h"
>  #include "hw/misc/aspeed_peci.h"
> +#include "hw/char/serial.h"
>  
>  #define ASPEED_SPIS_NUM  2
>  #define ASPEED_EHCIS_NUM 2
>  #define ASPEED_WDTS_NUM  4
>  #define ASPEED_CPUS_NUM  2
>  #define ASPEED_MACS_NUM  4
> +#define ASPEED_UARTS_NUM 13
>  
>  struct AspeedSoCState {
>      /*< private >*/
> @@ -79,6 +81,7 @@ struct AspeedSoCState {
>      AspeedSDHCIState emmc;
>      AspeedLPCState lpc;
>      AspeedPECIState peci;
> +    SerialMM uart[ASPEED_UARTS_NUM];
>      uint32_t uart_default;
       ^^^^^^^^^^^^^^^^^^^^^^
       Forgot to remove this, I'll send a v2 really quick.
       The machine state should keep the one it has, but
       the SoC one should go away.
>      Clock *sysclk;
>      UnimplementedDeviceState iomem;
> @@ -176,6 +179,7 @@ enum {
>  
>  qemu_irq aspeed_soc_get_irq(AspeedSoCState *s, int dev);
>  void aspeed_soc_uart_init(AspeedSoCState *s);
> +void aspeed_soc_uart_set_chr(AspeedSoCState *s, int dev, Chardev *chr);
>  bool aspeed_soc_dram_init(AspeedSoCState *s, Error **errp);
>  void aspeed_mmio_map(AspeedSoCState *s, SysBusDevice *dev, int n, hwaddr 
> addr);
>  void aspeed_mmio_map_unimplemented(AspeedSoCState *s, SysBusDevice *dev,
> -- 
> 2.37.0
> 
>