soc/apollolake: Pass earliest timestamp to timestamp_init

We have a timestamp from before cache-as-ram setup saved in the MMX
registers. Recover that timestamp, and use it as the base timestamp
rather than letting lib/bootblock.c use a late timestamp.

This allows more accurate profiling of the boot flow, since CAR setup
time is no longer excluded from the timing information.

Change-Id: I055092c600438c5260ab67509434a38f1eb77fe4
Signed-off-by: Alexandru Gagniuc <alexandrux.gagniuc@intel.com>
Reviewed-on: https://review.coreboot.org/14863
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/soc/intel/apollolake/bootblock/bootblock.c

@@ -26,6 +26,7 @@
 #include <soc/northbridge.h>
 #include <soc/pci_devs.h>
 #include <soc/uart.h>
+#include <timestamp.h>
 
 static const struct pad_config tpm_spi_configs[] = {
 	PAD_CFG_NF(GPIO_106, NATIVE, DEEP, NF3),	/* FST_SPI_CS2_N */
@@ -53,7 +54,7 @@ static void enable_pm_timer(void)
 	wrmsr(MSR_EMULATE_PM_TMR, msr);
 }
 
-void asmlinkage bootblock_c_entry(void)
+void asmlinkage bootblock_c_entry(uint32_t tsc_hi, uint32_t tsc_lo)
 {
 	device_t dev = NB_DEV_ROOT;
 
@@ -67,7 +68,7 @@ void asmlinkage bootblock_c_entry(void)
 	pci_write_config16(dev, PCI_COMMAND, PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY);
 
 	/* Call lib/bootblock.c main */
-	main();
+	bootblock_main_with_timestamp(((uint64_t)tsc_hi << 32) | tsc_lo);
 }
 
 static void cache_bios_region(void)

src/soc/intel/apollolake/bootblock/cache_as_ram.S

@@ -129,6 +129,12 @@ car_init_done:
 before_carstage:
 	post_code(0x2b)
 
+	/* Restore the timestamp from bootblock_crt0.S (mm2:mm1) */
+	movd	%mm1, %eax
+	push	%eax
+	movd	%mm2, %eax
+	push	%eax
+
 	/* We can call into C functions now */
 	call bootblock_c_entry
 

src/soc/intel/apollolake/include/soc/bootblock.h

@@ -16,5 +16,5 @@
 #define _SOC_APOLLOLAKE_BOOTBLOCK_H_
 #include <arch/cpu.h>
 
-void asmlinkage bootblock_c_entry(void);
+void asmlinkage bootblock_c_entry(uint32_t tsc_hi, uint32_t tsc_lo);
 #endif