arch/x86: Simplify <arch/early_variables.h>

This enables the use of .bss section for ENV_BOOTBLOCK
and ENV_VERSTAGE even with CAR_GLOBAL_MIGRATION=y.

In practice, boards with CAR_GLOBAL_MIGRATION=y currently
build with romcc-bootblock so they will not be using .bss.

Change-Id: Ie9dc14f3e528d3e4f48304f4d7de50df448a8af6
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/35016
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>
This commit is contained in:
Kyösti Mälkki 2019-08-22 09:44:44 +03:00
parent 19e1d631e3
commit a165c07ed7
5 changed files with 23 additions and 45 deletions

View File

@ -76,8 +76,8 @@
* cbmem console. This is useful for clearing this area on a per-stage
* basis when more than one stage uses cache-as-ram for CAR_GLOBALs. */
_car_global_start = .;
#if !CONFIG(CAR_GLOBAL_MIGRATION)
/* Allow global unitialized variables when CAR_GLOBALs are not used. */
#if ENV_STAGE_HAS_BSS_SECTION
/* Allow global uninitialized variables for stages without CAR teardown. */
*(.bss)
*(.bss.*)
*(.sbss)

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@ -20,7 +20,8 @@
#include <commonlib/helpers.h>
#include <stdlib.h>
#if ENV_CACHE_AS_RAM && CONFIG(CAR_GLOBAL_MIGRATION)
#if ENV_ROMSTAGE && CONFIG(CAR_GLOBAL_MIGRATION)
asm(".section .car.global_data,\"w\",@nobits");
asm(".previous");
#ifdef __clang__
@ -29,27 +30,6 @@ asm(".previous");
#define CAR_GLOBAL __attribute__((used, section(".car.global_data#")))
#endif /* __clang__ */
/*
* In stages that use CAR (verstage, C bootblock) all CAR_GLOBAL variables are
* accessed unconditionally because cbmem is never initialized until romstage
* when dram comes up.
*/
#if !ENV_ROMSTAGE
static inline void *car_get_var_ptr(void *var)
{
return var;
}
static inline void *car_sync_var_ptr(void *var)
{
return var;
}
static inline int car_active(void)
{
return 1;
}
#else
/* Get the correct pointer for the CAR global variable. */
void *car_get_var_ptr(void *var);
@ -58,7 +38,6 @@ void *car_sync_var_ptr(void *var);
/* Return 1 when currently running with globals in Cache-as-RAM, 0 otherwise. */
int car_active(void);
#endif /* !ENV_ROMSTAGE */
/* Get and set a primitive type global variable. */
#define car_get_var(var) \
@ -81,26 +60,25 @@ static inline size_t car_object_offset(void *ptr)
#else
/*
* We might end up here if:
* 1. ENV_CACHE_AS_RAM is not set for the stage or
* 2. ENV_CACHE_AS_RAM is set for the stage but CONFIG_CAR_GLOBAL_MIGRATION
* is not set. In this case, there is no need to migrate CAR global
* variables. But, since we might still be running out of CAR, car_active needs
* to return 1 if ENV_CACHE_AS_RAM is set.
* For all stages other than romstage, all CAR_GLOBAL variables are accessed
* unconditionally as there is no migration of symbols.
*/
#define CAR_GLOBAL
static inline void *car_get_var_ptr(void *var) { return var; }
#if ENV_CACHE_AS_RAM
static inline int car_active(void) { return 1; }
#else
static inline int car_active(void) { return 0; }
#endif /* ENV_CACHE_AS_RAM */
#define car_get_var(var) (var)
#define car_sync_var(var) (var)
#define car_set_var(var, val) (var) = (val)
#endif /* ENV_CACHE_AS_RAM && CONFIG(CAR_GLOBAL_MIGRATION) */
static inline void *car_get_var_ptr(void *var)
{
return var;
}
static inline int car_active(void)
{
return ENV_CACHE_AS_RAM;
}
#endif
#endif /* ARCH_EARLY_VARIABLES_H */

View File

@ -363,7 +363,7 @@ static int read_from_cbfs(const char *name, void *buf, size_t size)
int paging_enable_for_car(const char *pdpt_name, const char *pt_name)
{
if (!ENV_CACHE_AS_RAM)
if (!preram_symbols_available())
return -1;
if (read_from_cbfs(pdpt_name, _pdpt, REGION_SIZE(pdpt))) {
@ -383,7 +383,7 @@ int paging_enable_for_car(const char *pdpt_name, const char *pt_name)
static void *get_pdpt_addr(void)
{
if (ENV_CACHE_AS_RAM)
if (preram_symbols_available())
return _pdpt;
return (void *)(uintptr_t)read_cr3();
}

View File

@ -274,8 +274,8 @@
#define ENV_CACHE_AS_RAM ENV_ROMSTAGE_OR_BEFORE
/* No .data sections with execute-in-place from ROM. */
#define ENV_STAGE_HAS_DATA_SECTION !ENV_CACHE_AS_RAM
/* No .bss sections with execute-in-place from ROM. */
#define ENV_STAGE_HAS_BSS_SECTION !ENV_CACHE_AS_RAM
/* No .bss sections for stage with CAR teardown. */
#define ENV_STAGE_HAS_BSS_SECTION !(ENV_ROMSTAGE && CONFIG(CAR_GLOBAL_MIGRATION))
#else
/* Both .data and .bss, sometimes SRAM not DRAM. */
#define ENV_STAGE_HAS_DATA_SECTION 1

View File

@ -125,7 +125,7 @@
}
#endif
#if ENV_STAGE_HAS_BSS_SECTION
#if ENV_STAGE_HAS_BSS_SECTION && !ENV_CACHE_AS_RAM
.bss . : {
. = ALIGN(ARCH_POINTER_ALIGN_SIZE);
_bss = .;