From b267ab2c532a69931c44e4fb43d249f756ed053f Mon Sep 17 00:00:00 2001 From: Sughosh Ganu Date: Mon, 17 Mar 2025 14:03:55 +0530 Subject: efi_loader: remove unused code from copy_fdt() There is logic in the copy_fdt() function which is iterating over the platform's DRAM banks and setting the fdt_ram_start variable. However, this variable is not used subsequently in the function. Remove this superfluous code. Signed-off-by: Sughosh Ganu Reviewed-by: Ilias Apalodimas Reviewed-by: Heinrich Schuchardt Signed-off-by: Ilias Apalodimas --- lib/efi_loader/efi_helper.c | 14 +------------- 1 file changed, 1 insertion(+), 13 deletions(-) (limited to 'lib/efi_loader/efi_helper.c') diff --git a/lib/efi_loader/efi_helper.c b/lib/efi_loader/efi_helper.c index 04b2efc4a3b..15ad042bc61 100644 --- a/lib/efi_loader/efi_helper.c +++ b/lib/efi_loader/efi_helper.c @@ -454,23 +454,11 @@ efi_status_t efi_env_set_load_options(efi_handle_t handle, */ static efi_status_t copy_fdt(void **fdtp) { - unsigned long fdt_ram_start = -1L, fdt_pages; + unsigned long fdt_pages; efi_status_t ret = 0; void *fdt, *new_fdt; u64 new_fdt_addr; uint fdt_size; - int i; - - for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) { - u64 ram_start = gd->bd->bi_dram[i].start; - u64 ram_size = gd->bd->bi_dram[i].size; - - if (!ram_size) - continue; - - if (ram_start < fdt_ram_start) - fdt_ram_start = ram_start; - } /* * Give us at least 12 KiB of breathing room in case the device tree -- cgit v1.2.3 From 7e624377e99314bdfac6cb5a3d216dff49a047e9 Mon Sep 17 00:00:00 2001 From: Sughosh Ganu Date: Mon, 17 Mar 2025 14:03:56 +0530 Subject: efi_loader: install device-tree on configuration table on every invocation The efi_install_fdt() function is called before booting an EFI binary, either directly, or through a bootmanager. This function installs a copy of the device-tree(DT) on the EFI configuration table, which is passed on to the OS. The current logic in this function does not install a DT if a device-tree is already installed as an EFI configuration table. However, this existing copy of the DT might not be up-to-date, or it could be a wrong DT for the image that is being booted. Always install a DT afresh to the configuration table before booting the EFI binary. Installing a new DT also involves some additional checks that are needed to clean up memory associated with the existing DT copy. Check for an existing copy, and free up that memory. Signed-off-by: Sughosh Ganu Signed-off-by: Ilias Apalodimas --- lib/efi_loader/efi_helper.c | 39 +++++++++++++++++++++++++++++---------- 1 file changed, 29 insertions(+), 10 deletions(-) (limited to 'lib/efi_loader/efi_helper.c') diff --git a/lib/efi_loader/efi_helper.c b/lib/efi_loader/efi_helper.c index 15ad042bc61..f6fbcdffe82 100644 --- a/lib/efi_loader/efi_helper.c +++ b/lib/efi_loader/efi_helper.c @@ -454,11 +454,30 @@ efi_status_t efi_env_set_load_options(efi_handle_t handle, */ static efi_status_t copy_fdt(void **fdtp) { - unsigned long fdt_pages; efi_status_t ret = 0; void *fdt, *new_fdt; - u64 new_fdt_addr; - uint fdt_size; + static u64 new_fdt_addr; + static efi_uintn_t fdt_pages; + ulong fdt_size; + + /* + * Remove the configuration table that might already be + * installed, ignoring EFI_NOT_FOUND if no device-tree + * is installed + */ + efi_install_configuration_table(&efi_guid_fdt, NULL); + + if (new_fdt_addr) { + log_debug("%s: Found allocated memory at %#llx, with %#zx pages\n", + __func__, new_fdt_addr, fdt_pages); + + ret = efi_free_pages(new_fdt_addr, fdt_pages); + if (ret != EFI_SUCCESS) + log_err("Unable to free up existing FDT memory region\n"); + + new_fdt_addr = 0; + fdt_pages = 0; + } /* * Give us at least 12 KiB of breathing room in case the device tree @@ -473,15 +492,18 @@ static efi_status_t copy_fdt(void **fdtp) &new_fdt_addr); if (ret != EFI_SUCCESS) { log_err("Failed to reserve space for FDT\n"); - goto done; + return ret; } + log_debug("%s: Allocated memory at %#llx, with %#zx pages\n", + __func__, new_fdt_addr, fdt_pages); + new_fdt = (void *)(uintptr_t)new_fdt_addr; memcpy(new_fdt, fdt, fdt_totalsize(fdt)); fdt_set_totalsize(new_fdt, fdt_size); - *fdtp = (void *)(uintptr_t)new_fdt_addr; -done: - return ret; + *fdtp = new_fdt; + + return EFI_SUCCESS; } /** @@ -534,9 +556,6 @@ efi_status_t efi_install_fdt(void *fdt) const char *fdt_opt; uintptr_t fdt_addr; - /* Look for device tree that is already installed */ - if (efi_get_configuration_table(&efi_guid_fdt)) - return EFI_SUCCESS; /* Check if there is a hardware device tree */ fdt_opt = env_get("fdt_addr"); /* Use our own device tree as fallback */ -- cgit v1.2.3 From 61e0a20aecf4af6cdc223bd8cd1bd82fe5e3d9f6 Mon Sep 17 00:00:00 2001 From: Sughosh Ganu Date: Mon, 17 Mar 2025 14:04:02 +0530 Subject: blkmap: pass information on ISO image to the OS The EFI HTTP boot puts the ISO installer image at some location in memory. Information about this image has to be passed on to the OS kernel, which is done by adding a persistent memory(pmem) node to the devicetree(DT) that is passed to the OS. The OS kernel then gets information about the presence of this ISO image and proceeds with the installation. In U-Boot, this ISO image gets mounted as a memory mapped blkmap device slice, with the 'preserve' attribute. Add a helper function which iterates through all such slices, and invokes a callback. The callback adds the pmem node to the DT and removes the corresponding memory region from the EFI memory map. Invoke this helper function as part of the DT fixup which happens before booting the OS. Signed-off-by: Sughosh Ganu Reviewed-by: Tobias Waldekranz Signed-off-by: Ilias Apalodimas --- lib/efi_loader/efi_helper.c | 42 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) (limited to 'lib/efi_loader/efi_helper.c') diff --git a/lib/efi_loader/efi_helper.c b/lib/efi_loader/efi_helper.c index f6fbcdffe82..8c32059edda 100644 --- a/lib/efi_loader/efi_helper.c +++ b/lib/efi_loader/efi_helper.c @@ -5,6 +5,7 @@ #define LOG_CATEGORY LOGC_EFI +#include #include #include #include @@ -687,3 +688,44 @@ out: return ret; } + +/** + * pmem_node_efi_memmap_setup() - Add pmem node and tweak EFI memmap + * @fdt: The devicetree to which pmem node is added + * @addr: start address of the pmem node + * @size: size of the memory of the pmem node + * + * The function adds the pmem node to the device-tree along with removing + * the corresponding region from the EFI memory map. Used primarily to + * pass the information of a RAM based ISO image to the OS. + * + * Return: 0 on success, -ve value on error + */ +static int pmem_node_efi_memmap_setup(void *fdt, u64 addr, u64 size) +{ + int ret; + u64 pages; + efi_status_t status; + + ret = fdt_fixup_pmem_region(fdt, addr, size); + if (ret) { + log_err("Failed to setup pmem node for addr %#llx, size %#llx, err %d\n", + addr, size, ret); + return ret; + } + + /* Remove the pmem region from the EFI memory map */ + pages = efi_size_in_pages(size + (addr & EFI_PAGE_MASK)); + status = efi_update_memory_map(addr, pages, EFI_CONVENTIONAL_MEMORY, + false, true); + if (status != EFI_SUCCESS) + return -1; + + return 0; +} + +int fdt_efi_pmem_setup(void *fdt) +{ + return blkmap_get_preserved_pmem_slices(pmem_node_efi_memmap_setup, + fdt); +} -- cgit v1.2.3