New patch to review for coreboot: postcar_loader: Support LATE_CBMEM_INIT boards

[Kyösti Mälkki]

Kyösti Mälkki ([e-mail]) just uploaded a new patch set to gerrit, which you can find at https://review.coreboot.org/17700

-gerrit

commit 15a71c351d159c2f24b1b8146e97719edf7d373a
Author: Kyösti Mälkki 
Date:   Fri Dec 2 19:47:07 2016 +0200

postcar_loader: Support LATE_CBMEM_INIT boards

Create postcar_frame object without placing stack in CBMEM.
    This way same cache_as_ram.inc code can be used unmodified.

Change-Id: Ic5ed404ce268ee881e9893dd434534231aa2bc88
    Signed-off-by: Kyösti Mälkki 
---
 src/arch/x86/include/arch/cpu.h |  5 +++++
 src/arch/x86/postcar_loader.c   | 31 +++++++++++++++++++++----------
 2 files changed, 26 insertions(+), 10 deletions(-)

diff --git a/src/arch/x86/include/arch/cpu.h b/src/arch/x86/include/arch/cpu.h
index faa2375..d33bb92 100644
--- a/src/arch/x86/include/arch/cpu.h
+++ b/src/arch/x86/include/arch/cpu.h
@@ -268,6 +268,11 @@ struct postcar_frame {
 int postcar_frame_init(struct postcar_frame *pcf, size_t stack_size);

/*
+ * Initialize postcar_frame object with a fixed stacktop in low memory.
+ */
+void postcar_frame_init_lowmem(struct postcar_frame *pcf);
+
+/*
  * Add variable MTRR covering the provided range with MTRR type.
  */
 void postcar_frame_add_mtrr(struct postcar_frame *pcf,
diff --git a/src/arch/x86/postcar_loader.c b/src/arch/x86/postcar_loader.c
index 948e445..11d05b4 100644
--- a/src/arch/x86/postcar_loader.c
+++ b/src/arch/x86/postcar_loader.c
@@ -32,13 +32,20 @@ static inline void stack_push(struct postcar_frame *pcf, uint32_t val)
    *ptr = val;
 }

-int postcar_frame_init(struct postcar_frame *pcf, size_t stack_size)
+static void postcar_frame_prepare(struct postcar_frame *pcf)
 {
-	void *stack;
    msr_t msr;
-
    msr = rdmsr(MTRR_CAP_MSR);

+	pcf->upper_mask = (1 << (cpu_phys_address_size() - 32)) - 1;
+	pcf->max_var_mttrs = msr.lo & MTRR_CAP_VCNT;
+	pcf->num_var_mttrs = 0;
+}
+
+int postcar_frame_init(struct postcar_frame *pcf, size_t stack_size)
+{
+	void *stack;
+
    stack = cbmem_add(CBMEM_ID_ROMSTAGE_RAM_STACK, stack_size);
    if (stack == NULL) {
    	printk(BIOS_ERR, "Couldn't add %zd byte stack in cbmem.\n",
@@ -46,18 +53,22 @@ int postcar_frame_init(struct postcar_frame *pcf, size_t stack_size)
    	return -1;
    }

+	postcar_frame_prepare(pcf);
    pcf->stack = (uintptr_t)stack;
    pcf->stack += stack_size;
-
-	pcf->upper_mask = (1 << (cpu_phys_address_size() - 32)) - 1;
-
-	pcf->max_var_mttrs = msr.lo & MTRR_CAP_VCNT;
-
-	pcf->num_var_mttrs = 0;
-
    return 0;
 }

+/*
+ * For use with LATE_CBMEM_INIT boards only, with a fixed stacktop in
+ * low memory.
+ */
+void postcar_frame_init_lowmem(struct postcar_frame *pcf)
+{
+	postcar_frame_prepare(pcf);
+	pcf->stack = CONFIG_RAMTOP;
+}
+
 void postcar_frame_add_mtrr(struct postcar_frame *pcf,
    			uintptr_t addr, size_t size, int type)
 {