[MIPS] MT: Enable coexistence of AP/SP with VSMP and SMTC.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/Kconfig

@@ -1377,17 +1377,6 @@ config MIPS_MT_SMTC
 	  This is a kernel model which is known a SMTC or lately has been
 	  marketesed into SMVP.
 
-config MIPS_VPE_LOADER
-	bool "VPE loader support."
-	depends on SYS_SUPPORTS_MULTITHREADING
-	select CPU_MIPSR2_IRQ_VI
-	select CPU_MIPSR2_IRQ_EI
-	select CPU_MIPSR2_SRS
-	select MIPS_MT
-	help
-	  Includes a loader for loading an elf relocatable object
-	  onto another VPE and running it.
-
 endchoice
 
 config MIPS_MT
@@ -1398,8 +1387,19 @@ config SYS_SUPPORTS_MULTITHREADING
 
 config MIPS_MT_FPAFF
 	bool "Dynamic FPU affinity for FP-intensive threads"
-	depends on MIPS_MT
 	default y
+	depends on MIPS_MT_SMP || MIPS_MT_SMTC
+
+config MIPS_VPE_LOADER
+	bool "VPE loader support."
+	depends on SYS_SUPPORTS_MULTITHREADING
+	select CPU_MIPSR2_IRQ_VI
+	select CPU_MIPSR2_IRQ_EI
+	select CPU_MIPSR2_SRS
+	select MIPS_MT
+	help
+	  Includes a loader for loading an elf relocatable object
+	  onto another VPE and running it.
 
 config MIPS_MT_SMTC_INSTANT_REPLAY
 	bool "Low-latency Dispatch of Deferred SMTC IPIs"

arch/mips/kernel/kspd.c

@@ -89,7 +89,7 @@ static int sp_stopping = 0;
 #define MTSP_O_EXCL		0x0800
 #define MTSP_O_BINARY		0x8000
 
-#define SP_VPE 1
+extern int tclimit;
 
 struct apsp_table  {
 	int sp;
@@ -225,8 +225,8 @@ void sp_work_handle_request(void)
 	/* Run the syscall at the priviledge of the user who loaded the
 	   SP program */
 
-	if (vpe_getuid(SP_VPE))
-		sp_setfsuidgid( vpe_getuid(SP_VPE), vpe_getgid(SP_VPE));
+	if (vpe_getuid(tclimit))
+		sp_setfsuidgid(vpe_getuid(tclimit), vpe_getgid(tclimit));
 
 	switch (sc.cmd) {
 	/* needs the flags argument translating from SDE kit to
@@ -245,7 +245,7 @@ void sp_work_handle_request(void)
 
  	case MTSP_SYSCALL_EXIT:
 		list_for_each_entry(n, &kspd_notifylist, list)
- 			n->kspd_sp_exit(SP_VPE);
+			n->kspd_sp_exit(tclimit);
 		sp_stopping = 1;
 
 		printk(KERN_DEBUG "KSPD got exit syscall from SP exitcode %d\n",
@@ -255,7 +255,7 @@ void sp_work_handle_request(void)
  	case MTSP_SYSCALL_OPEN:
  		generic.arg1 = translate_open_flags(generic.arg1);
 
- 		vcwd = vpe_getcwd(SP_VPE);
+		vcwd = vpe_getcwd(tclimit);
 
  		/* change to the cwd of the process that loaded the SP program */
 		old_fs = get_fs();
@@ -283,7 +283,7 @@ void sp_work_handle_request(void)
 		break;
  	} /* switch */
 
-	if (vpe_getuid(SP_VPE))
+	if (vpe_getuid(tclimit))
 		sp_setfsuidgid( 0, 0);
 
 	old_fs = get_fs();
@@ -364,10 +364,9 @@ static void startwork(int vpe)
 		}
 
 		INIT_WORK(&work, sp_work);
-		queue_work(workqueue, &work);
-	} else
-		queue_work(workqueue, &work);
+	}
 
+	queue_work(workqueue, &work);
 }
 
 static void stopwork(int vpe)
@@ -389,7 +388,7 @@ static int kspd_module_init(void)
 
 	notify.start = startwork;
 	notify.stop = stopwork;
-	vpe_notify(SP_VPE, &notify);
+	vpe_notify(tclimit, &notify);
 
 	return 0;
 }

arch/mips/kernel/mips-mt.c

@@ -21,6 +21,28 @@
 #include <asm/r4kcache.h>
 #include <asm/cacheflush.h>
 
+int vpelimit;
+
+static int __init maxvpes(char *str)
+{
+	get_option(&str, &vpelimit);
+
+	return 1;
+}
+
+__setup("maxvpes=", maxvpes);
+
+int tclimit;
+
+static int __init maxtcs(char *str)
+{
+	get_option(&str, &tclimit);
+
+	return 1;
+}
+
+__setup("maxtcs=", maxtcs);
+
 /*
  * Dump new MIPS MT state for the core. Does not leave TCs halted.
  * Takes an argument which taken to be a pre-call MVPControl value.

arch/mips/kernel/rtlx.c

@@ -40,12 +40,11 @@
 #include <asm/atomic.h>
 #include <asm/cpu.h>
 #include <asm/processor.h>
+#include <asm/mips_mt.h>
 #include <asm/system.h>
 #include <asm/vpe.h>
 #include <asm/rtlx.h>
 
-#define RTLX_TARG_VPE 1
-
 static struct rtlx_info *rtlx;
 static int major;
 static char module_name[] = "rtlx";
@@ -165,10 +164,10 @@ int rtlx_open(int index, int can_sleep)
 	}
 
 	if (rtlx == NULL) {
-		if( (p = vpe_get_shared(RTLX_TARG_VPE)) == NULL) {
+		if( (p = vpe_get_shared(tclimit)) == NULL) {
 			if (can_sleep) {
 				__wait_event_interruptible(channel_wqs[index].lx_queue,
-				                           (p = vpe_get_shared(RTLX_TARG_VPE)),
+				                           (p = vpe_get_shared(tclimit)),
 				                           ret);
 				if (ret)
 					goto out_fail;
@@ -477,6 +476,19 @@ static int rtlx_module_init(void)
 	struct device *dev;
 	int i, err;
 
+	if (!cpu_has_mipsmt) {
+		printk("VPE loader: not a MIPS MT capable processor\n");
+		return -ENODEV;
+	}
+
+	if (tclimit == 0) {
+		printk(KERN_WARNING "No TCs reserved for AP/SP, not "
+		       "initializing RTLX.\nPass maxtcs=<n> argument as kernel "
+		       "argument\n");
+
+		return -ENODEV;
+	}
+
 	major = register_chrdev(0, module_name, &rtlx_fops);
 	if (major < 0) {
 		printk(register_chrdev_failed);
@@ -501,7 +513,7 @@ static int rtlx_module_init(void)
 	/* set up notifiers */
 	notify.start = starting;
 	notify.stop = stopping;
-	vpe_notify(RTLX_TARG_VPE, &notify);
+	vpe_notify(tclimit, &notify);
 
 	if (cpu_has_vint)
 		set_vi_handler(MIPS_CPU_RTLX_IRQ, rtlx_dispatch);

arch/mips/kernel/smtc.c

@@ -86,25 +86,11 @@ unsigned int smtc_status = 0;
 
 /* Boot command line configuration overrides */
 
-static int vpelimit = 0;
-static int tclimit = 0;
 static int ipibuffers = 0;
 static int nostlb = 0;
 static int asidmask = 0;
 unsigned long smtc_asid_mask = 0xff;
 
-static int __init maxvpes(char *str)
-{
-	get_option(&str, &vpelimit);
-	return 1;
-}
-
-static int __init maxtcs(char *str)
-{
-	get_option(&str, &tclimit);
-	return 1;
-}
-
 static int __init ipibufs(char *str)
 {
 	get_option(&str, &ipibuffers);
@@ -137,8 +123,6 @@ static int __init asidmask_set(char *str)
 	return 1;
 }
 
-__setup("maxvpes=", maxvpes);
-__setup("maxtcs=", maxtcs);
 __setup("ipibufs=", ipibufs);
 __setup("nostlb", stlb_disable);
 __setup("asidmask=", asidmask_set);

include/asm-mips/mips_mt.h

@@ -8,6 +8,12 @@
 
 #include <linux/cpumask.h>
 
+/*
+ * How many VPEs and TCs is Linux allowed to use?  0 means no limit.
+ */
+extern int tclimit;
+extern int vpelimit;
+
 extern cpumask_t mt_fpu_cpumask;
 extern unsigned long mt_fpemul_threshold;