soc/intel/common: Calculate and configure SF Mask 2

As per TGL EDS, two ways will be controlled with one bit of SF QoS
register hence, this patch introduces SF_MASK_2WAYS_PER_BIT Kconfig to
allow SoC users to select SF_MASK_2WAYS_PER_BIT to follow the EDS
recommendation.

Calculate SF masks 2:
1. if CONFIG_SF_MASK_2WAYS_PER_BIT:
        a. data_ways = data_ways / 2

Also, program SF Mask#2 using below logic:
2. Set SF_MASK_2 = (1 << data_ways) - 1

Change-Id: I442bed75f13d26f357cfb32c54c5fe9efa4b474b
Signed-off-by: Subrata Banik <subrata.banik@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/56717
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>

src/include/cpu/x86/msr.h

@@ -88,6 +88,8 @@
 #define IA32_HWP_CAPABILITIES		0x771
 #define IA32_HWP_REQUEST		0x774
 #define IA32_HWP_STATUS			0x777
+#define IA32_SF_QOS_INFO		0xc87
+#define  IA32_SF_WAY_COUNT_MASK		0x3f
 #define IA32_PQR_ASSOC			0xc8f
 /* MSR bits 33:32 encode slot number 0-3 */
 #define  IA32_PQR_ASSOC_MASK		(1 << 0 | 1 << 1)

src/soc/intel/common/block/cpu/Kconfig

@@ -63,6 +63,14 @@ config CAR_HAS_SF_MASKS
 	  IA32_L3_SF_MASK_x programming is required along with the data ways.
 	  This is applicable for TGL and beyond.
 
+config SF_MASK_2WAYS_PER_BIT
+	bool
+	depends on INTEL_CAR_NEM_ENHANCED
+	help
+	  In the case of non-inclusive cache architecture when two ways in
+	  the SF mask are controlled by one bit of the SF QoS register.
+	  This is applicable for TGL alone.
+
 config COS_MAPPED_TO_MSB
 	bool
 	depends on INTEL_CAR_NEM_ENHANCED

src/soc/intel/common/block/cpu/car/cache_as_ram.S

@@ -499,6 +499,7 @@ find_llc_subleaf:
 	 * of RW data.
 	 */
 	movl	$0x01, %eax
+	mov	%eax, %edx /* back up data_ways in edx */
 	cmp	$CONFIG_DCACHE_RAM_SIZE, %ecx
 	jnc	set_eviction_mask
 
@@ -508,6 +509,7 @@ find_llc_subleaf:
 	 */
 	mov	$CONFIG_DCACHE_RAM_SIZE, %eax
 	div	%ecx
+	mov	%eax, %edx /* back up data_ways in edx */
 	mov	%eax, %ecx
 	movl	$0x01, %eax
 	shl	%cl, %eax
@@ -517,6 +519,29 @@ set_eviction_mask:
 	mov	%ebx, %edi /* back up number of ways */
 	mov	%eax, %esi /* back up the non-eviction mask */
 #if CONFIG(CAR_HAS_SF_MASKS)
+	mov	%edx, %eax /* restore data_ways in eax */
+	/*
+	 * Calculate SF masks 2:
+	 * 1. if CONFIG_SF_MASK_2WAYS_PER_BIT: data_ways = data_ways / 2
+	 * 2. Program MSR 0x1892 Non-Eviction Mask #2
+	 *    IA32_CR_SF_QOS_MASK_2 = ((1 << data_ways) - 1)
+	 */
+#if CONFIG(SF_MASK_2WAYS_PER_BIT)
+	cmp	$0x01, %eax /* Skip Step 1 if data_ways = 1 */
+	jz	program_sf2
+	movl	$0x01, %ecx /* Step 1 */
+	shr	%cl, %eax
+#endif
+	/* Step 2 */
+	mov	%eax, %ecx
+	movl	$0x01, %eax
+	shl	%cl, %eax
+	subl	$0x01, %eax
+program_sf2:
+	xorl	%edx, %edx
+	mov	$IA32_CR_SF_QOS_MASK_2, %ecx
+	wrmsr
+
 	/*
 	 * SF mask is programmed with the double number of bits than
 	 * the number of ways