MIPS: Netlogic: XLP2XX CPU and PIC frequency

Add code to calculate the CPU and PIC frequency for XLP2XX SoCs.

Since the PIC frequency on XLP2XX can be configured, add a new macro
pic_timer_freq() to be used in netlogic/common/time.c.
Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Cc: Ganesan Ramalingam <ganesanr@broadcom.com>
Patchwork: http://patchwork.linux-mips.org/patch/5701/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/include/asm/netlogic/xlp-hal/pic.h

@@ -208,13 +208,14 @@
 #define PIC_LOCAL_SCHEDULING		1
 #define PIC_GLOBAL_SCHEDULING		0
 
-#define PIC_CLK_HZ			133333333
-
 #define nlm_read_pic_reg(b, r)	nlm_read_reg64(b, r)
 #define nlm_write_pic_reg(b, r, v) nlm_write_reg64(b, r, v)
 #define nlm_get_pic_pcibase(node) nlm_pcicfg_base(XLP_IO_PIC_OFFSET(node))
 #define nlm_get_pic_regbase(node) (nlm_get_pic_pcibase(node) + XLP_IO_PCI_HDRSZ)
 
+/* We use PIC on node 0 as a timer */
+#define pic_timer_freq()		nlm_get_pic_frequency(0)
+
 /* IRT and h/w interrupt routines */
 static inline int
 nlm_pic_read_irt(uint64_t base, int irt_index)

arch/mips/include/asm/netlogic/xlp-hal/sys.h

@@ -117,6 +117,36 @@
 #define SYS_SCRTCH2				0x4b
 #define SYS_SCRTCH3				0x4c
 
+/* PLL registers XLP2XX */
+#define SYS_PLL_CTRL0				0x240
+#define SYS_PLL_CTRL1				0x241
+#define SYS_PLL_CTRL2				0x242
+#define SYS_PLL_CTRL3				0x243
+#define SYS_DMC_PLL_CTRL0			0x244
+#define SYS_DMC_PLL_CTRL1			0x245
+#define SYS_DMC_PLL_CTRL2			0x246
+#define SYS_DMC_PLL_CTRL3			0x247
+
+#define SYS_PLL_CTRL0_DEVX(x)			(0x248 + (x) * 4)
+#define SYS_PLL_CTRL1_DEVX(x)			(0x249 + (x) * 4)
+#define SYS_PLL_CTRL2_DEVX(x)			(0x24a + (x) * 4)
+#define SYS_PLL_CTRL3_DEVX(x)			(0x24b + (x) * 4)
+
+#define SYS_CPU_PLL_CHG_CTRL			0x288
+#define SYS_PLL_CHG_CTRL			0x289
+#define SYS_CLK_DEV_DIS				0x28a
+#define SYS_CLK_DEV_SEL				0x28b
+#define SYS_CLK_DEV_DIV				0x28c
+#define SYS_CLK_DEV_CHG				0x28d
+#define SYS_CLK_DEV_SEL_REG			0x28e
+#define SYS_CLK_DEV_DIV_REG			0x28f
+#define SYS_CPU_PLL_LOCK			0x29f
+#define SYS_SYS_PLL_LOCK			0x2a0
+#define SYS_PLL_MEM_CMD				0x2a1
+#define SYS_CPU_PLL_MEM_REQ			0x2a2
+#define SYS_SYS_PLL_MEM_REQ			0x2a3
+#define SYS_PLL_MEM_STAT			0x2a4
+
 #ifndef __ASSEMBLY__
 
 #define nlm_read_sys_reg(b, r)		nlm_read_reg(b, r)
@@ -124,5 +154,6 @@
 #define nlm_get_sys_pcibase(node) nlm_pcicfg_base(XLP_IO_SYS_OFFSET(node))
 #define nlm_get_sys_regbase(node) (nlm_get_sys_pcibase(node) + XLP_IO_PCI_HDRSZ)
 
+unsigned int nlm_get_pic_frequency(int node);
 #endif
 #endif

arch/mips/include/asm/netlogic/xlr/pic.h

@@ -36,6 +36,8 @@
 #define _ASM_NLM_XLR_PIC_H
 
 #define PIC_CLK_HZ			66666666
+#define pic_timer_freq()		PIC_CLK_HZ
+
 /* PIC hardware interrupt numbers */
 #define PIC_IRT_WD_INDEX		0
 #define PIC_IRT_TIMER_0_INDEX		1

arch/mips/netlogic/common/time.c

@@ -45,6 +45,7 @@
 #if defined(CONFIG_CPU_XLP)
 #include <asm/netlogic/xlp-hal/iomap.h>
 #include <asm/netlogic/xlp-hal/xlp.h>
+#include <asm/netlogic/xlp-hal/sys.h>
 #include <asm/netlogic/xlp-hal/pic.h>
 #elif defined(CONFIG_CPU_XLR)
 #include <asm/netlogic/xlr/iomap.h>
@@ -91,7 +92,7 @@ static void nlm_init_pic_timer(void)
 		csrc_pic.read	= nlm_get_pic_timer;
 	}
 	csrc_pic.rating = 1000;
-	clocksource_register_hz(&csrc_pic, PIC_CLK_HZ);
+	clocksource_register_hz(&csrc_pic, pic_timer_freq());
 }
 
 void __init plat_time_init(void)

arch/mips/netlogic/xlp/nlm_hal.c

@@ -127,6 +127,10 @@ unsigned int nlm_get_core_frequency(int node, int core)
 
 	sysbase = nlm_get_node(node)->sysbase;
 	rstval = nlm_read_sys_reg(sysbase, SYS_POWER_ON_RESET_CFG);
+	if (cpu_is_xlpii()) {
+		num = 1000000ULL * (400 * 3 + 100 * (rstval >> 26));
+		denom = 3;
+	} else {
 		dfsval = nlm_read_sys_reg(sysbase, SYS_CORE_DFS_DIV_VALUE);
 		pll_divf = ((rstval >> 10) & 0x7f) + 1;
 		pll_divr = ((rstval >> 8)  & 0x3) + 1;
@@ -135,10 +139,113 @@ unsigned int nlm_get_core_frequency(int node, int core)
 
 		num = 800000000ULL * pll_divf;
 		denom = 3 * pll_divr * ext_div * dfs_div;
+	}
 	do_div(num, denom);
 	return (unsigned int)num;
 }
 
+/* Calculate Frequency to the PIC from PLL.
+ * freq_out = ( ref_freq/2 * (6 + ctrl2[7:0]) + ctrl2[20:8]/2^13 ) /
+ * ((2^ctrl0[7:5]) * Table(ctrl0[26:24]))
+ */
+static unsigned int nlm_2xx_get_pic_frequency(int node)
+{
+	u32 ctrl_val0, ctrl_val2, vco_post_div, pll_post_div;
+	u32 mdiv, fdiv, pll_out_freq_den, reg_select, ref_div, pic_div;
+	u64 ref_clk, sysbase, pll_out_freq_num, ref_clk_select;
+
+	sysbase = nlm_get_node(node)->sysbase;
+
+	/* Find ref_clk_base */
+	ref_clk_select =
+		(nlm_read_sys_reg(sysbase, SYS_POWER_ON_RESET_CFG) >> 18) & 0x3;
+	switch (ref_clk_select) {
+	case 0:
+		ref_clk = 200000000ULL;
+		ref_div = 3;
+		break;
+	case 1:
+		ref_clk = 100000000ULL;
+		ref_div = 1;
+		break;
+	case 2:
+		ref_clk = 125000000ULL;
+		ref_div = 1;
+		break;
+	case 3:
+		ref_clk = 400000000ULL;
+		ref_div = 3;
+		break;
+	}
+
+	/* Find the clock source PLL device for PIC */
+	reg_select = (nlm_read_sys_reg(sysbase, SYS_CLK_DEV_SEL) >> 22) & 0x3;
+	switch (reg_select) {
+	case 0:
+		ctrl_val0 = nlm_read_sys_reg(sysbase, SYS_PLL_CTRL0);
+		ctrl_val2 = nlm_read_sys_reg(sysbase, SYS_PLL_CTRL2);
+		break;
+	case 1:
+		ctrl_val0 = nlm_read_sys_reg(sysbase, SYS_PLL_CTRL0_DEVX(0));
+		ctrl_val2 = nlm_read_sys_reg(sysbase, SYS_PLL_CTRL2_DEVX(0));
+		break;
+	case 2:
+		ctrl_val0 = nlm_read_sys_reg(sysbase, SYS_PLL_CTRL0_DEVX(1));
+		ctrl_val2 = nlm_read_sys_reg(sysbase, SYS_PLL_CTRL2_DEVX(1));
+		break;
+	case 3:
+		ctrl_val0 = nlm_read_sys_reg(sysbase, SYS_PLL_CTRL0_DEVX(2));
+		ctrl_val2 = nlm_read_sys_reg(sysbase, SYS_PLL_CTRL2_DEVX(2));
+		break;
+	}
+
+	vco_post_div = (ctrl_val0 >> 5) & 0x7;
+	pll_post_div = (ctrl_val0 >> 24) & 0x7;
+	mdiv = ctrl_val2 & 0xff;
+	fdiv = (ctrl_val2 >> 8) & 0xfff;
+
+	/* Find PLL post divider value */
+	switch (pll_post_div) {
+	case 1:
+		pll_post_div = 2;
+		break;
+	case 3:
+		pll_post_div = 4;
+		break;
+	case 7:
+		pll_post_div = 8;
+		break;
+	case 6:
+		pll_post_div = 16;
+		break;
+	case 0:
+	default:
+		pll_post_div = 1;
+		break;
+	}
+
+	fdiv = fdiv/(1 << 13);
+	pll_out_freq_num = ((ref_clk >> 1) * (6 + mdiv)) + fdiv;
+	pll_out_freq_den = (1 << vco_post_div) * pll_post_div * 3;
+
+	if (pll_out_freq_den > 0)
+		do_div(pll_out_freq_num, pll_out_freq_den);
+
+	/* PIC post divider, which happens after PLL */
+	pic_div = (nlm_read_sys_reg(sysbase, SYS_CLK_DEV_DIV) >> 22) & 0x3;
+	do_div(pll_out_freq_num, 1 << pic_div);
+
+	return pll_out_freq_num;
+}
+
+unsigned int nlm_get_pic_frequency(int node)
+{
+	if (cpu_is_xlpii())
+		return nlm_2xx_get_pic_frequency(node);
+	else
+		return 133333333;
+}
+
 unsigned int nlm_get_cpu_frequency(void)
 {
 	return nlm_get_core_frequency(0, 0);