Secure memory is at the end of memory, separated and reserved from OS, tracked by gd->secure_ram. Secure memory can host MMU tables, security monitor, etc.
Signed-off-by: York Sun yorksun@freescale.com
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Changes in v3: Put ifdef around secure_ram Move defining CONFIG_SYS_MEM_RESERVE_SECURE to patch 2/2
Changes in v2: Do not use CONFIG_SYS_MEM_TOP_HIDE mechanism
Changes in v1: Initial patch. Depends on http://patchwork.ozlabs.org/patch/540248/
README | 8 ++++++++ common/board_f.c | 9 +++++++++ include/asm-generic/global_data.h | 4 ++++ 3 files changed, 21 insertions(+)
diff --git a/README b/README index ef8d437..61cbc82 100644 --- a/README +++ b/README @@ -3881,6 +3881,14 @@ Configuration Settings: Scratch address used by the alternate memory test You only need to set this if address zero isn't writeable
+- CONFIG_SYS_MEM_RESERVE_SECURE + If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory + is substracted from total RAM and won't be reported to OS. + This memory can be used as secure memory. A variable + gd->secure_ram is used to track the location. In systems + the RAM base is not zero, or RAM is divided into banks, + this variable needs to be recalcuated to get the address. + - CONFIG_SYS_MEM_TOP_HIDE (PPC only): If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, this specified memory area will get subtracted from the top diff --git a/common/board_f.c b/common/board_f.c index 725eb18..8061105 100644 --- a/common/board_f.c +++ b/common/board_f.c @@ -323,6 +323,15 @@ static int setup_dest_addr(void) * Ram is setup, size stored in gd !! */ debug("Ram size: %08lX\n", (ulong)gd->ram_size); +#ifdef CONFIG_SYS_MEM_RESERVE_SECURE + /* Reserve memory for secure MMU tables, and/or security monitor */ + gd->ram_size -= CONFIG_SYS_MEM_RESERVE_SECURE; + /* + * Record secure memory location. Need recalcuate if memory splits + * into banks, or the ram base is not zero. + */ + gd->secure_ram = gd->ram_size; +#endif #if defined(CONFIG_SYS_MEM_TOP_HIDE) /* * Subtract specified amount of memory to hide so that it won't diff --git a/include/asm-generic/global_data.h b/include/asm-generic/global_data.h index d0383f3..8cdafd6 100644 --- a/include/asm-generic/global_data.h +++ b/include/asm-generic/global_data.h @@ -58,6 +58,10 @@ typedef struct global_data {
unsigned long relocaddr; /* Start address of U-Boot in RAM */ phys_size_t ram_size; /* RAM size */ +#ifdef CONFIG_SYS_MEM_RESERVE_SECURE + /* Secure memory addr. LSB is a flag for "secured". */ + phys_addr_t secure_ram; +#endif unsigned long mon_len; /* monitor len */ unsigned long irq_sp; /* irq stack pointer */ unsigned long start_addr_sp; /* start_addr_stackpointer */