bootstub: optimizations and cleanup of bootstub

BZ: 98228

Optimizations of bootstub code:
 -clean up naming (replacing mrst references to mid where applicable)
 -Code  size reduction
 -increase code efficiency
 -change uart functionality to more accurately support on other platforms.
   Instead of assuming SPI 0 for non recognized SOCs, will now skip spi/uart
   initializations and simply return from print routines
 -increase version to 1.3

Change-Id: Id355fa64d53422cb8fa28e4fd5155e0e1b9d0b55
Signed-off-by: Eric Ernst <eric.ernst@intel.com>
Reviewed-on: http://android.intel.com:8080/99552
Reviewed-by: Gao, Bin <bin.gao@intel.com>
Reviewed-by: Chouleur, Sylvain <sylvain.chouleur@intel.com>
Reviewed-by: Noziska, Patrick J <patrick.j.noziska@intel.com>
Reviewed-by: Yang, Fei <fei.yang@intel.com>
Tested-by: Ng, Cheon-woei <cheon-woei.ng@intel.com>
Reviewed-by: buildbot <buildbot@intel.com>
Tested-by: buildbot <buildbot@intel.com>

3 files changed, 52 insertions, 33 deletions

diff --git a/bootstub.c b/bootstub.c
index 26c96d2..fb1d765 100644
--- a/bootstub.c
+++ b/bootstub.c
@@ -27,6 +27,8 @@
 
 #define bs_printk(x) { if (! *(int *)SPI_UART_SUPPRESSION) bs_spi_printk(x);}
 
+extern int no_uart_used;
+
 static void *memcpy(void *dest, const void *src, size_t count)
 {
         char *tmp = dest;
@@ -95,7 +97,7 @@ static void setup_boot_params(struct boot_params *bp, struct setup_header *sh)
 	} else {
 		bs_printk("Won't relocate initramfs, are you in SLE?\n");
 	}
-	if (mrst_identify_cpu() == MRST_CPU_CHIP_VALLEYVIEW2) {
+	if (mid_identify_cpu() == MID_CPU_CHIP_VALLEYVIEW2) {
 		nr_entries = get_e820_by_bios(bp->e820_map);
 		bp->e820_entries = (nr_entries > 0) ? nr_entries : 0;
 	} else {
@@ -133,33 +135,44 @@ enum cpuid_regs {
 	CR_EBX
 };
 
-int mrst_identify_cpu(void)
+int mid_identify_cpu(void)
 {
 	u32 regs[4];
 
 	cpuid(1, &regs[CR_EAX], &regs[CR_EBX], &regs[CR_ECX], &regs[CR_EDX]);
 
-	if ((regs[CR_EAX] & CPUID_MASK) == PENWELL_FAMILY)
-		return MRST_CPU_CHIP_PENWELL;
-	else if ((regs[CR_EAX] & CPUID_MASK) == CLOVERVIEW_FAMILY)
-		return MRST_CPU_CHIP_CLOVERVIEW;
-	else if ((regs[CR_EAX] & CPUID_MASK) == VALLEYVIEW2_FAMILY)
-		return MRST_CPU_CHIP_VALLEYVIEW2;
-	return MRST_CPU_CHIP_LINCROFT;
+	switch ( regs[CR_EAX] & CPUID_MASK ) {
+
+	case PENWELL_FAMILY:
+		return MID_CPU_CHIP_PENWELL;
+	case CLOVERVIEW_FAMILY:
+		return MID_CPU_CHIP_CLOVERVIEW;
+	case VALLEYVIEW2_FAMILY:
+		return MID_CPU_CHIP_VALLEYVIEW2;
+	default:
+		return MID_CPU_CHIP_OTHER;
+	}
 }
 
 static void setup_spi(void)
 {
 	if (!(*(int *)SPI_TYPE)) {
-		if (mrst_identify_cpu() == MRST_CPU_CHIP_PENWELL) {
-			*(int *)SPI_TYPE = 1;
-			bs_printk("Penwell detected ...\n");
-		} else if (mrst_identify_cpu() == MRST_CPU_CHIP_CLOVERVIEW) {
-			*(int *)SPI_TYPE = 1;
-			bs_printk("Cloverview detected ...\n");
-		} else {
-			*(int *)SPI_TYPE = 1;
-			bs_printk("Lincroft detected ...\n");
+		switch ( mid_identify_cpu() ) {
+
+		case MID_CPU_CHIP_PENWELL:
+			*(int *)SPI_TYPE = SPI_1;
+			bs_printk("PNW detected\n");
+			break;
+
+		case MID_CPU_CHIP_CLOVERVIEW:
+			*(int *)SPI_TYPE = SPI_1;
+			bs_printk("CLV detected\n");
+			break;
+
+		case MID_CPU_CHIP_VALLEYVIEW2:
+		case MID_CPU_CHIP_OTHER:
+		default:
+			no_uart_used = 1;
 		}
 	}
 }
@@ -167,7 +180,7 @@ static void setup_spi(void)
 int bootstub(void)
 {
 	setup_spi();
-	bs_printk("Bootstub Version: 1.2 ...\n");
+	bs_printk("Bootstub Version: 1.3 ...\n");
 	setup_boot_params((struct boot_params *)BOOT_PARAMS_OFFSET, 
 		(struct setup_header *)SETUP_HEADER_OFFSET);
 	bs_printk("Jump to kernel 32bit entry ...\n");
diff --git a/bootstub.h b/bootstub.h
index b1fc0d5..8db1690 100644
--- a/bootstub.h
+++ b/bootstub.h
@@ -9,16 +9,20 @@
 #define CLOVERVIEW_FAMILY	0x30650
 #define VALLEYVIEW2_FAMILY	0x30670
 
-#define MRST_CPU_CHIP_LINCROFT	1
-#define MRST_CPU_CHIP_PENWELL	2
-#define MRST_CPU_CHIP_CLOVERVIEW 3
-#define MRST_CPU_CHIP_VALLEYVIEW2 4
+#define MID_CPU_CHIP_LINCROFT	1
+#define MID_CPU_CHIP_PENWELL	2
+#define MID_CPU_CHIP_CLOVERVIEW 3
+#define MID_CPU_CHIP_VALLEYVIEW2 4
+#define MID_CPU_CHIP_OTHER		0xFF
 
 #define CMDLINE_OFFSET		0x1100000
 #define BZIMAGE_SIZE_OFFSET	(CMDLINE_OFFSET + CMDLINE_SIZE)
 #define INITRD_SIZE_OFFSET	(BZIMAGE_SIZE_OFFSET + 4)
 #define SPI_UART_SUPPRESSION	(INITRD_SIZE_OFFSET + 4)
 #define SPI_TYPE		(SPI_UART_SUPPRESSION + 4) /*0:SPI0  1:SPI1*/
+#define SPI_0		0
+#define SPI_1		1
+
 #define STACK_OFFSET		0x1101000
 #define BZIMAGE_OFFSET		0x1102000
 
@@ -48,7 +52,7 @@
          ((u64)(base & 0x00ffffff) << 16) |     \
          ((u64)(limit & 0x0000ffff)))
 int get_e820_by_bios(void *e820_buf);
-int mrst_identify_cpu(void);
+int mid_identify_cpu(void);
 #endif
 
 #endif
diff --git a/spi-uart.c b/spi-uart.c
index 7ff8323..ffe5676 100644
--- a/spi-uart.c
+++ b/spi-uart.c
@@ -22,6 +22,7 @@
 
 #define MRST_SPI_TIMEOUT	0x200000
 static int spi_inited = 0;
+int no_uart_used = 0;
 static volatile struct mrst_spi_reg *pspi = 0;
 
 static void spi_init()
@@ -30,24 +31,21 @@ static void spi_init()
 	u32 *clk_reg, clk_cdiv;
 
 	switch (*(int *)SPI_TYPE) {
-	case 0:
-		if (mrst_identify_cpu() == MRST_CPU_CHIP_CLOVERVIEW)
-			pspi = (struct mrst_spi_reg *)CTP_REGBASE_SPI0;
-		else
-			pspi = (struct mrst_spi_reg *)MRST_REGBASE_SPI0;
-		break;
-	case 1:
-		if (mrst_identify_cpu() == MRST_CPU_CHIP_CLOVERVIEW)
+	case SPI_1:
+		if (mid_identify_cpu() == MID_CPU_CHIP_CLOVERVIEW)
 			pspi = (struct mrst_spi_reg *)CTP_REGBASE_SPI1;
 		else
 			pspi = (struct mrst_spi_reg *)MRST_REGBASE_SPI1;
 		break;
+
+	case SPI_0:
 	default:
-		if (mrst_identify_cpu() == MRST_CPU_CHIP_CLOVERVIEW)
+		if (mid_identify_cpu() == MID_CPU_CHIP_CLOVERVIEW)
 			pspi = (struct mrst_spi_reg *)CTP_REGBASE_SPI0;
 		else
 			pspi = (struct mrst_spi_reg *)MRST_REGBASE_SPI0;
 	}
+
 	/* disable SPI controller first */
 	pspi->ssienr = 0x0;
 
@@ -75,6 +73,7 @@ static void spi_init()
 	pspi->ssienr |= 0x1;
 
 	spi_inited = 1;
+
 }
 
 /* set the ratio rate, INT */
@@ -122,6 +121,9 @@ static int spi_max3110_putc(char c)
 
 void bs_spi_printk(const char *str)
 {
+	if ( no_uart_used )
+		return;
+
 	if (!spi_inited) {
 		spi_init();
 		max3110_write_config();