Re: [PATCH v7 8/8] mac_oldworld: Add SPD data to cover RAM

[Philippe Mathieu-Daudé]

On 6/29/20 8:55 PM, BALATON Zoltan wrote:
> OpenBIOS gets RAM size via fw_cfg but rhe original board firmware

Typo "the".

> detects RAM using SPD data so generate and add SDP eeproms to cover as

EEPROMs?

> much RAM as possible to describe with SPD (this may be less than the
> actual ram_size due to SDRAM size constraints).
>
> This patch is more complex as it should be which I intend to fix once
> agreement can be made on how to get back the necessary functionality
> removed by previous patches. See in this thread:
> https://lists.nongnu.org/archive/html/qemu-devel/2020-06/msg08710.html
>
> Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
> ---
>   hw/ppc/mac_oldworld.c | 19 ++++++++++++++++++-
>   1 file changed, 18 insertions(+), 1 deletion(-)
>
> diff --git a/hw/ppc/mac_oldworld.c b/hw/ppc/mac_oldworld.c
> index 6276973c95..6a27287c9f 100644
> --- a/hw/ppc/mac_oldworld.c
> +++ b/hw/ppc/mac_oldworld.c
> @@ -34,6 +34,7 @@
>   #include "hw/input/adb.h"
>   #include "sysemu/sysemu.h"
>   #include "net/net.h"
> +#include "hw/i2c/smbus_eeprom.h"
>   #include "hw/isa/isa.h"
>   #include "hw/pci/pci.h"
>   #include "hw/pci/pci_host.h"
> @@ -104,6 +105,8 @@ static void ppc_heathrow_init(MachineState *machine)
>       DriveInfo *hd[MAX_IDE_BUS * MAX_IDE_DEVS];
>       void *fw_cfg;
>       uint64_t tbfreq;
> +    uint8_t *spd_data[3] = {};
> +    I2CBus *i2c_bus;
>   
>       /* init CPUs */
>       for (i = 0; i < smp_cpus; i++) {
> @@ -121,8 +124,16 @@ static void ppc_heathrow_init(MachineState *machine)
>                        "maximum 2047 MB", ram_size / MiB);
>           exit(1);
>       }
> -
>       memory_region_add_subregion(get_system_memory(), 0, machine->ram);
> +    for (i = 0; i < 3; i++) {

3 -> ARRAY_SIZE(spd_data)

> +        int size_left = ram_size - i * 512 * MiB;
> +        if (size_left > 0) {
> +            uint32_t s = size_left / MiB;
> +            s = (s > 512 ? 512 : s);

MIN()?

> +            s = 1U << (31 - clz32(s));
> +            spd_data[i] = spd_data_generate(SDR, s * MiB);
> +        }
> +    }
>   
>       /* allocate and load firmware ROM */
>       memory_region_init_rom(bios, NULL, "ppc_heathrow.bios", PROM_SIZE,
> @@ -302,6 +313,12 @@ static void ppc_heathrow_init(MachineState *machine)
>       macio_ide_init_drives(macio_ide, &hd[MAX_IDE_DEVS]);
>   
>       dev = DEVICE(object_resolve_path_component(OBJECT(macio), "cuda"));
> +    i2c_bus = I2C_BUS(qdev_get_child_bus(dev, "i2c"));
> +    for (i = 0; i < 3; i++) {

3 -> ARRAY_SIZE(spd_data)

> +        if (spd_data[i]) {
> +            smbus_eeprom_init_one(i2c_bus, 0x50 + i, spd_data[i]);
> +        }
> +    }
>       adb_bus = qdev_get_child_bus(dev, "adb.0");
>       dev = qdev_new(TYPE_ADB_KEYBOARD);
>       qdev_realize_and_unref(dev, adb_bus, &error_fatal);