diff mbox series

[v4,01/39] arm: init: export prev_bl_fdt_addr

Message ID 20240215-b4-qcom-common-target-v4-1-ed06355c634a@linaro.org
State Superseded
Headers show
Series Qualcomm generic board support | expand

Commit Message

Caleb Connolly Feb. 15, 2024, 8:52 p.m. UTC
When booting U-Boot on board with a locked down first-stage bootloader,
we emulate the Linux boot header. By passing the U-Boot FDT through this
first-stage bootloader and retrieving it afterwards we can pre-populate
the memory nodes and other info like the KASLR address.

Add a function to export the FDT addr so that boards can use it over the
built-in FDT.

Don't check is_addr_accessible() here because we might not yet have a
valid mem_map if it's going to be populated from the FDT, let the board
do their own validation instead.

Reviewed-by: Tom Rini <trini@konsulko.com>
Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>
---
 arch/arm/lib/save_prev_bl_data.c |  5 +++++
 include/init.h                   | 11 +++++++++++
 2 files changed, 16 insertions(+)

Comments

Sumit Garg Feb. 20, 2024, 5:41 a.m. UTC | #1
On Fri, 16 Feb 2024 at 02:22, Caleb Connolly <caleb.connolly@linaro.org> wrote:
>
> When booting U-Boot on board with a locked down first-stage bootloader,
> we emulate the Linux boot header. By passing the U-Boot FDT through this
> first-stage bootloader and retrieving it afterwards we can pre-populate
> the memory nodes and other info like the KASLR address.
>
> Add a function to export the FDT addr so that boards can use it over the
> built-in FDT.
>
> Don't check is_addr_accessible() here because we might not yet have a
> valid mem_map if it's going to be populated from the FDT, let the board
> do their own validation instead.
>
> Reviewed-by: Tom Rini <trini@konsulko.com>
> Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>
> ---
>  arch/arm/lib/save_prev_bl_data.c |  5 +++++
>  include/init.h                   | 11 +++++++++++
>  2 files changed, 16 insertions(+)

Reviewed-by: Sumit Garg <sumit.garg@linaro.org>

-Sumit

>
> diff --git a/arch/arm/lib/save_prev_bl_data.c b/arch/arm/lib/save_prev_bl_data.c
> index f7b23faf0d66..b286bac9bf00 100644
> --- a/arch/arm/lib/save_prev_bl_data.c
> +++ b/arch/arm/lib/save_prev_bl_data.c
> @@ -45,6 +45,11 @@ bool is_addr_accessible(phys_addr_t addr)
>         return false;
>  }
>
> +phys_addr_t get_prev_bl_fdt_addr(void)
> +{
> +       return reg0;
> +}
> +
>  int save_prev_bl_data(void)
>  {
>         struct fdt_header *fdt_blob;
> diff --git a/include/init.h b/include/init.h
> index 9a1951d10a01..630d86729c4e 100644
> --- a/include/init.h
> +++ b/include/init.h
> @@ -168,6 +168,17 @@ defined(CONFIG_SAVE_PREV_BL_FDT_ADDR)
>   * Return: 0 if ok; -ENODATA on error
>   */
>  int save_prev_bl_data(void);
> +
> +/**
> + * get_prev_bl_fdt_addr - When u-boot is chainloaded, get the address
> + * of the FDT passed by the previous bootloader.
> + *
> + * Return: the address of the FDT passed by the previous bootloader
> + * or 0 if not found.
> + */
> +phys_addr_t get_prev_bl_fdt_addr(void);
> +#else
> +#define get_prev_bl_fdt_addr() 0LLU
>  #endif
>
>  /**
>
> --
> 2.43.1
>
diff mbox series

Patch

diff --git a/arch/arm/lib/save_prev_bl_data.c b/arch/arm/lib/save_prev_bl_data.c
index f7b23faf0d66..b286bac9bf00 100644
--- a/arch/arm/lib/save_prev_bl_data.c
+++ b/arch/arm/lib/save_prev_bl_data.c
@@ -45,6 +45,11 @@  bool is_addr_accessible(phys_addr_t addr)
 	return false;
 }
 
+phys_addr_t get_prev_bl_fdt_addr(void)
+{
+	return reg0;
+}
+
 int save_prev_bl_data(void)
 {
 	struct fdt_header *fdt_blob;
diff --git a/include/init.h b/include/init.h
index 9a1951d10a01..630d86729c4e 100644
--- a/include/init.h
+++ b/include/init.h
@@ -168,6 +168,17 @@  defined(CONFIG_SAVE_PREV_BL_FDT_ADDR)
  * Return: 0 if ok; -ENODATA on error
  */
 int save_prev_bl_data(void);
+
+/**
+ * get_prev_bl_fdt_addr - When u-boot is chainloaded, get the address
+ * of the FDT passed by the previous bootloader.
+ *
+ * Return: the address of the FDT passed by the previous bootloader
+ * or 0 if not found.
+ */
+phys_addr_t get_prev_bl_fdt_addr(void);
+#else
+#define get_prev_bl_fdt_addr() 0LLU
 #endif
 
 /**