From: Peter Maydell Date: Thu, 6 Feb 2025 15:12:12 +0000 (+0000) Subject: hw/mips/boston: Support dumpdtb monitor commands X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=db0dd33559ee97a1fe84a1272258646279aca2e2;p=qemu.git hw/mips/boston: Support dumpdtb monitor commands The boston machine doesn't set MachineState::fdt to the DTB blob that it has loaded or created, which means that the QMP/HMP dumpdtb monitor commands don't work. Setting MachineState::fdt is easy in the non-FIT codepath: we can simply do so immediately before loading the DTB into guest memory. The FIT codepath is a bit more awkward as currently the FIT loader throws away the memory that the FDT was in after it loads it into guest memory. So we add a void *pfdt argument to load_fit() for it to store the FDT pointer into. There is some readjustment required of the pointer handling in loader-fit.c, so that it applies 'const' only where it should (e.g. the data pointer we get back from fdt_getprop() is const, because it's into the middle of the input FDT data, but the pointer that fit_load_image_alloc() should not be const, because it's freshly allocated memory that the caller can change if it likes). Signed-off-by: Peter Maydell Reviewed-by: Philippe Mathieu-Daudé Message-id: 20250206151214.2947842-5-peter.maydell@linaro.org --- diff --git a/hw/core/loader-fit.c b/hw/core/loader-fit.c index 9bdd4fa17c..6eb66406b0 100644 --- a/hw/core/loader-fit.c +++ b/hw/core/loader-fit.c @@ -32,8 +32,8 @@ #define FIT_LOADER_MAX_PATH (128) -static const void *fit_load_image_alloc(const void *itb, const char *name, - int *poff, size_t *psz, Error **errp) +static void *fit_load_image_alloc(const void *itb, const char *name, + int *poff, size_t *psz, Error **errp) { const void *data; const char *comp; @@ -80,11 +80,11 @@ static const void *fit_load_image_alloc(const void *itb, const char *name, return NULL; } - data = g_realloc(uncomp_data, uncomp_len); + uncomp_data = g_realloc(uncomp_data, uncomp_len); if (psz) { *psz = uncomp_len; } - return data; + return uncomp_data; } error_setg(errp, "unknown compression '%s'", comp); @@ -177,13 +177,12 @@ out: static int fit_load_fdt(const struct fit_loader *ldr, const void *itb, int cfg, void *opaque, const void *match_data, - hwaddr kernel_end, Error **errp) + hwaddr kernel_end, void **pfdt, Error **errp) { ERRP_GUARD(); Error *err = NULL; const char *name; - const void *data; - const void *load_data; + void *data; hwaddr load_addr; int img_off; size_t sz; @@ -194,7 +193,7 @@ static int fit_load_fdt(const struct fit_loader *ldr, const void *itb, return 0; } - load_data = data = fit_load_image_alloc(itb, name, &img_off, &sz, errp); + data = fit_load_image_alloc(itb, name, &img_off, &sz, errp); if (!data) { error_prepend(errp, "unable to load FDT image from FIT: "); return -EINVAL; @@ -211,19 +210,23 @@ static int fit_load_fdt(const struct fit_loader *ldr, const void *itb, } if (ldr->fdt_filter) { - load_data = ldr->fdt_filter(opaque, data, match_data, &load_addr); + void *filtered_data; + + filtered_data = ldr->fdt_filter(opaque, data, match_data, &load_addr); + if (filtered_data != data) { + g_free(data); + data = filtered_data; + } } load_addr = ldr->addr_to_phys(opaque, load_addr); - sz = fdt_totalsize(load_data); - rom_add_blob_fixed(name, load_data, sz, load_addr); + sz = fdt_totalsize(data); + rom_add_blob_fixed(name, data, sz, load_addr); - ret = 0; + *pfdt = data; + return 0; out: g_free((void *) data); - if (data != load_data) { - g_free((void *) load_data); - } return ret; } @@ -259,7 +262,8 @@ out: return ret; } -int load_fit(const struct fit_loader *ldr, const char *filename, void *opaque) +int load_fit(const struct fit_loader *ldr, const char *filename, + void **pfdt, void *opaque) { Error *err = NULL; const struct fit_loader_match *match; @@ -323,7 +327,7 @@ int load_fit(const struct fit_loader *ldr, const char *filename, void *opaque) goto out; } - ret = fit_load_fdt(ldr, itb, cfg_off, opaque, match_data, kernel_end, + ret = fit_load_fdt(ldr, itb, cfg_off, opaque, match_data, kernel_end, pfdt, &err); if (ret) { error_report_err(err); diff --git a/hw/mips/boston.c b/hw/mips/boston.c index de6ce1f163..79410dabe7 100644 --- a/hw/mips/boston.c +++ b/hw/mips/boston.c @@ -358,8 +358,8 @@ static void gen_firmware(void *p, hwaddr kernel_entry, hwaddr fdt_addr) kernel_entry); } -static const void *boston_fdt_filter(void *opaque, const void *fdt_orig, - const void *match_data, hwaddr *load_addr) +static void *boston_fdt_filter(void *opaque, const void *fdt_orig, + const void *match_data, hwaddr *load_addr) { BostonState *s = BOSTON(opaque); MachineState *machine = s->mach; @@ -797,7 +797,7 @@ static void boston_mach_init(MachineState *machine) if (kernel_size > 0) { int dt_size; g_autofree const void *dtb_file_data = NULL; - g_autofree const void *dtb_load_data = NULL; + void *dtb_load_data = NULL; hwaddr dtb_paddr = QEMU_ALIGN_UP(kernel_high, 64 * KiB); hwaddr dtb_vaddr = cpu_mips_phys_to_kseg0(NULL, dtb_paddr); @@ -815,6 +815,8 @@ static void boston_mach_init(MachineState *machine) exit(1); } + machine->fdt = dtb_load_data; + /* Calculate real fdt size after filter */ dt_size = fdt_totalsize(dtb_load_data); rom_add_blob_fixed("dtb", dtb_load_data, dt_size, dtb_paddr); @@ -822,7 +824,8 @@ static void boston_mach_init(MachineState *machine) rom_ptr(dtb_paddr, dt_size)); } else { /* Try to load file as FIT */ - fit_err = load_fit(&boston_fit_loader, machine->kernel_filename, s); + fit_err = load_fit(&boston_fit_loader, machine->kernel_filename, + &machine->fdt, s); if (fit_err) { error_report("unable to load kernel image"); exit(1); diff --git a/include/hw/loader-fit.h b/include/hw/loader-fit.h index 0832e379dc..9a43490ed6 100644 --- a/include/hw/loader-fit.h +++ b/include/hw/loader-fit.h @@ -30,12 +30,27 @@ struct fit_loader_match { struct fit_loader { const struct fit_loader_match *matches; hwaddr (*addr_to_phys)(void *opaque, uint64_t addr); - const void *(*fdt_filter)(void *opaque, const void *fdt, - const void *match_data, hwaddr *load_addr); + void *(*fdt_filter)(void *opaque, const void *fdt, + const void *match_data, hwaddr *load_addr); const void *(*kernel_filter)(void *opaque, const void *kernel, hwaddr *load_addr, hwaddr *entry_addr); }; -int load_fit(const struct fit_loader *ldr, const char *filename, void *opaque); +/** + * load_fit: load a FIT format image + * @ldr: structure defining board specific properties and hooks + * @filename: image to load + * @pfdt: pointer to update with address of FDT blob + * @opaque: opaque value passed back to the hook functions in @ldr + * Returns: 0 on success, or a negative errno on failure + * + * @pfdt is used to tell the caller about the FDT blob. On return, it + * has been set to point to the FDT blob, and it is now the caller's + * responsibility to free that memory with g_free(). Usually the caller + * will want to pass in &machine->fdt here, to record the FDT blob for + * the dumpdtb option and QMP/HMP commands. + */ +int load_fit(const struct fit_loader *ldr, const char *filename, void **pfdt, + void *opaque); #endif /* HW_LOADER_FIT_H */