Re: [PATCH v4 5/7] hw/ppc/e500: Implement pflash handling

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 28/10/22 17:09, Daniel Henrique Barboza wrote:
> Bernhard,
> 
> The 32 builds aren't fancying this patch. The issue is down there:
> 
> On 10/18/22 18:01, Bernhard Beschow wrote:
>> Allows e500 boards to have their root file system reside on flash using
>> only builtin devices located in the eLBC memory region.
>>
>> Note that the flash memory area is only created when a -pflash 
>> argument is
>> given, and that the size is determined by the given file. The idea is to
>> put users into control.
>>
>> Signed-off-by: Bernhard Beschow <shentey@gmail.com>
>> ---
>>   docs/system/ppc/ppce500.rst | 16 ++++++++
>>   hw/ppc/Kconfig              |  1 +
>>   hw/ppc/e500.c               | 79 +++++++++++++++++++++++++++++++++++++
>>   3 files changed, 96 insertions(+)

>> @@ -1024,6 +1061,48 @@ void ppce500_init(MachineState *machine)
>>                                   pmc->platform_bus_base,
>>                                   &pms->pbus_dev->mmio);
>> +    dinfo = drive_get(IF_PFLASH, 0, 0);
>> +    if (dinfo) {
>> +        BlockBackend *blk = blk_by_legacy_dinfo(dinfo);
>> +        BlockDriverState *bs = blk_bs(blk);
>> +        uint64_t size = bdrv_getlength(bs);
>> +        uint64_t mmio_size = pms->pbus_dev->mmio.size;
> 
> ^ here. The issue is that on a 32 bit system it is not possible to cast the
> Int128 type to uint64_t:
> 
> FAILED: libqemu-ppc64-softmmu.fa.p/hw_ppc_e500.c.o
> 3746cc -m32 -Ilibqemu-ppc64-softmmu.fa.p -I. -I.. -Itarget/ppc 
> -I../target/ppc -I../dtc/libfdt -Iqapi -Itrace -Iui -Iui/shader 
> -I/usr/include/pixman-1 -I/usr/include/glib-2.0 
> -I/usr/lib/glib-2.0/include -I/usr/include/sysprof-4 
> -fdiagnostics-color=auto -Wall -Winvalid-pch -Werror -std=gnu11 -O2 -g 
> -isystem /builds/danielhb/qemu/linux-headers -isystem linux-headers 
> -iquote . -iquote /builds/danielhb/qemu -iquote 
> /builds/danielhb/qemu/include -iquote /builds/danielhb/qemu/tcg/i386 
> -pthread -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -D_GNU_SOURCE 
> -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -Wstrict-prototypes 
> -Wredundant-decls -Wundef -Wwrite-strings -Wmissing-prototypes 
> -fno-strict-aliasing -fno-common -fwrapv -Wold-style-declaration 
> -Wold-style-definition -Wtype-limits -Wformat-security -Wformat-y2k 
> -Winit-self -Wignored-qualifiers -Wempty-body -Wnested-externs 
> -Wendif-labels -Wexpansion-to-defined -Wimplicit-fallthrough=2 
> -Wno-missing-include-dirs -Wno-shift-negative-value -Wno-psabi 
> -fstack-protector-strong -fPIE -isystem../linux-headers 
> -isystemlinux-headers -DNEED_CPU_H 
> '-DCONFIG_TARGET="ppc64-softmmu-config-target.h"' 
> '-DCONFIG_DEVICES="ppc64-softmmu-config-devices.h"' -MD -MQ 
> libqemu-ppc64-softmmu.fa.p/hw_ppc_e500.c.o -MF 
> libqemu-ppc64-softmmu.fa.p/hw_ppc_e500.c.o.d -o 
> libqemu-ppc64-softmmu.fa.p/hw_ppc_e500.c.o -c ../hw/ppc/e500.c
> 3747../hw/ppc/e500.c: In function 'ppce500_init':
> 3748../hw/ppc/e500.c:1069:30: error: incompatible types when 
> initializing type 'uint64_t' {aka 'long long unsigned int'} using type 
> 'Int128'
> 3749 1069 |         uint64_t mmio_size = pms->pbus_dev->mmio.size;
> 3750      |                              ^~~
> 3751[3207/5331] Compiling C object 
> libqemu-ppc64-softmmu.fa.p/hw_ppc_mpc8544_guts.c.o
> 
> 
> What I did to solve the problem is this:
> 
> 
> +         uint64_t mmio_size = int128_get64(pms->pbus_dev->mmio.size); >
> This will get the lower 64 bits and return an uint64_t.
> 
> Note that this function will assert if mmio.size is bigger than 
> UINT64_MAX, but
> since you're doing an error(1) on the "if size > mmio_size" conditional, 
> this
> assert() is not introducing a new side effect. We'll just fail earlier with
> a different error message.

Simply use:

   memory_region_size(pms->pbus_dev->mmio);