soc/intel/baytrail: Add native refcode replacement

- This is a reverse engineered re-implementation of refcode.elf on
	Bay Trail
- Tested on GBYT4, should work everywhere as it's meant to behave
	exactly the same as the binary refcode

Signed-off-by: Mate Kukri <kukri.mate@gmail.com>
Change-Id: I91977c509022b0078804dc151d27296260e24bc4
Reviewed-on: https://review.coreboot.org/c/coreboot/+/43133
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

1 files changed, 12 insertions, 2 deletions

diff --git a/src/soc/intel/baytrail/iosf.c b/src/soc/intel/baytrail/iosf.c
index 5a8331057e..21060eee1a 100644
--- a/src/soc/intel/baytrail/iosf.c
+++ b/src/soc/intel/baytrail/iosf.c
@@ -15,7 +15,7 @@ static inline uint32_t read_iosf_reg(int reg)
 }
 
 /* Common sequences for all the port accesses. */
-static uint32_t iosf_read_port(uint32_t cr, int reg)
+uint32_t iosf_read_port(uint32_t cr, int reg)
 {
 	cr |= IOSF_REG(reg) | IOSF_BYTE_EN;
 	write_iosf_reg(MCRX_REG, IOSF_REG_UPPER(reg));
@@ -23,7 +23,7 @@ static uint32_t iosf_read_port(uint32_t cr, int reg)
 	return read_iosf_reg(MDR_REG);
 }
 
-static void iosf_write_port(uint32_t cr, int reg, uint32_t val)
+void iosf_write_port(uint32_t cr, int reg, uint32_t val)
 {
 	cr |= IOSF_REG(reg) | IOSF_BYTE_EN;
 	write_iosf_reg(MDR_REG, val);
@@ -68,6 +68,16 @@ void iosf_dunit_write(int reg, uint32_t val)
 	iosf_write_port(IOSF_WRITE(SYSMEMC), reg, val);
 }
 
+uint32_t iosf_cunit_read(int reg)
+{
+	return iosf_read_port(IOSF_READ(CUNIT), reg);
+}
+
+void iosf_cunit_write(int reg, uint32_t val)
+{
+	iosf_write_port(IOSF_WRITE(CUNIT), reg, val);
+}
+
 uint32_t iosf_punit_read(int reg)
 {
 	return iosf_read_port(IOSF_READ(PMC), reg);