Re: [PATCH v5 6/7] hw/misc/mps2-scc: Use the LED device

[Luc Michel <luc.michel@greensocs.com>]

On 9/10/20 10:54 PM, Philippe Mathieu-Daudé wrote:
> Per the 'ARM MPS2 and MPS2+ FPGA Prototyping Boards Technical
> Reference Manual' (100112_0200_07_en):
> 
>    2.1  Overview of the MPS2 and MPS2+ hardware
> 
>         The MPS2 and MPS2+ FPGA Prototyping Boards contain the
>         following components and interfaces:
> 
>         * User switches and user LEDs:
> 
>           - Two green LEDs and two push buttons that connect to
>             the FPGA.
>           - Eight green LEDs and one 8-way dip switch that connect
>             to the MCC.
> 
> Add the 8 LEDs connected to the MCC.
> 
> This remplaces the 'mps2_scc_leds' trace events by the generic
replaces
> 'led_set_intensity' event.

Same as patch 5, I think you need to reset your LEDs in mps2_scc_reset.

Also, see below for a superfluous new line.

> 
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
> https://youtu.be/l9kD70uPchk?t=288
> ---
>   include/hw/misc/mps2-scc.h |  2 ++
>   hw/misc/mps2-scc.c         | 25 ++++++++++++++-----------
>   hw/misc/Kconfig            |  1 +
>   hw/misc/trace-events       |  1 -
>   4 files changed, 17 insertions(+), 12 deletions(-)
> 
> diff --git a/include/hw/misc/mps2-scc.h b/include/hw/misc/mps2-scc.h
> index 7045473788b..8542f384227 100644
> --- a/include/hw/misc/mps2-scc.h
> +++ b/include/hw/misc/mps2-scc.h
> @@ -13,6 +13,7 @@
>   #define MPS2_SCC_H
>   
>   #include "hw/sysbus.h"
> +#include "hw/misc/led.h"
>   
>   #define TYPE_MPS2_SCC "mps2-scc"
>   #define MPS2_SCC(obj) OBJECT_CHECK(MPS2SCC, (obj), TYPE_MPS2_SCC)
> @@ -25,6 +26,7 @@ typedef struct {
>   
>       /*< public >*/
>       MemoryRegion iomem;
> +    LEDState *led[8];
>   
>       uint32_t cfg0;
>       uint32_t cfg1;
> diff --git a/hw/misc/mps2-scc.c b/hw/misc/mps2-scc.c
> index 9d0909e7b35..745505b849d 100644
> --- a/hw/misc/mps2-scc.c
> +++ b/hw/misc/mps2-scc.c
> @@ -20,11 +20,13 @@
>   #include "qemu/osdep.h"
>   #include "qemu/log.h"
>   #include "qemu/module.h"
> +#include "qemu/bitops.h"
>   #include "trace.h"
>   #include "hw/sysbus.h"
>   #include "migration/vmstate.h"
>   #include "hw/registerfields.h"
>   #include "hw/misc/mps2-scc.h"
> +#include "hw/misc/led.h"
>   #include "hw/qdev-properties.h"
>   
>   REG32(CFG0, 0)
> @@ -152,18 +154,10 @@ static void mps2_scc_write(void *opaque, hwaddr offset, uint64_t value,
>           s->cfg0 = value;
>           break;
>       case A_CFG1:
> -        /* CFG1 bits [7:0] control the board LEDs. We don't currently have
> -         * a mechanism for displaying this graphically, so use a trace event.
> -         */
> -        trace_mps2_scc_leds(value & 0x80 ? '*' : '.',
> -                            value & 0x40 ? '*' : '.',
> -                            value & 0x20 ? '*' : '.',
> -                            value & 0x10 ? '*' : '.',
> -                            value & 0x08 ? '*' : '.',
> -                            value & 0x04 ? '*' : '.',
> -                            value & 0x02 ? '*' : '.',
> -                            value & 0x01 ? '*' : '.');
>           s->cfg1 = value;
> +        for (size_t i = 0; i < ARRAY_SIZE(s->led); i++) {
> +            led_set_state(s->led[i], extract32(value, i, 1));
> +        }
>           break;
>       case A_CFGDATA_OUT:
>           s->cfgdata_out = value;
> @@ -245,10 +239,19 @@ static void mps2_scc_init(Object *obj)
>   
>       memory_region_init_io(&s->iomem, obj, &mps2_scc_ops, s, "mps2-scc", 0x1000);
>       sysbus_init_mmio(sbd, &s->iomem);
> +
Superfluous new line.

-- 
Luc
>   }
>   
>   static void mps2_scc_realize(DeviceState *dev, Error **errp)
>   {
> +    MPS2SCC *s = MPS2_SCC(dev);
> +
> +    for (size_t i = 0; i < ARRAY_SIZE(s->led); i++) {
> +        char *name = g_strdup_printf("SCC LED%zu", i);
> +        s->led[i] = led_create_simple(OBJECT(dev), GPIO_POLARITY_ACTIVE_HIGH,
> +                                      LED_COLOR_GREEN, name);
> +        g_free(name);
> +    }
>   }
>   
>   static const VMStateDescription mps2_scc_vmstate = {
> diff --git a/hw/misc/Kconfig b/hw/misc/Kconfig
> index 0cecad45aad..7557a3e7b46 100644
> --- a/hw/misc/Kconfig
> +++ b/hw/misc/Kconfig
> @@ -97,6 +97,7 @@ config MPS2_FPGAIO
>   
>   config MPS2_SCC
>       bool
> +    select LED
>   
>   config TZ_MPC
>       bool
> diff --git a/hw/misc/trace-events b/hw/misc/trace-events
> index 43b9e0cf250..a620a358feb 100644
> --- a/hw/misc/trace-events
> +++ b/hw/misc/trace-events
> @@ -85,7 +85,6 @@ aspeed_scu_write(uint64_t offset, unsigned size, uint32_t data) "To 0x%" PRIx64
>   mps2_scc_read(uint64_t offset, uint64_t data, unsigned size) "MPS2 SCC read: offset 0x%" PRIx64 " data 0x%" PRIx64 " size %u"
>   mps2_scc_write(uint64_t offset, uint64_t data, unsigned size) "MPS2 SCC write: offset 0x%" PRIx64 " data 0x%" PRIx64 " size %u"
>   mps2_scc_reset(void) "MPS2 SCC: reset"
> -mps2_scc_leds(char led7, char led6, char led5, char led4, char led3, char led2, char led1, char led0) "MPS2 SCC LEDs: %c%c%c%c%c%c%c%c"
>   mps2_scc_cfg_write(unsigned function, unsigned device, uint32_t value) "MPS2 SCC config write: function %d device %d data 0x%" PRIx32
>   mps2_scc_cfg_read(unsigned function, unsigned device, uint32_t value) "MPS2 SCC config read: function %d device %d data 0x%" PRIx32
>   
>