powerpc: pseries, cell: use cpu_thread_in_core in smp_init for of_spin_map

powerpc: pseries, cell: use cpu_thread_in_core in smp_init for of_spin_map

[Milton Miller]

We used to assume that even numbered threads were the primary
threads, ie those that would be listed and started as a cpu from
open firmware.  Replace a left over is even (% 2) check with a check
for it being a primary thread and update the comments.

Tested with a debug print on pseries, identical code found for cell.

Signed-off-by: Milton Miller <miltonm@bga.com>
---
X-Patchwork-ID: 19578
Resend of July 11 patch, changelog edited.
Patch still applies to next-20081017.

Note: We assume the secondary threads are not spinning, but they are
actually spinning if we start via kexec.  This means that we call rtas to
spin up the secondary threads. If we get a bad return code from we skip
bringing the cpu online, leaving the thread spinning on the paca.  We don't
handle this case in kexec, and will leave the thread wild during another
kexec.  (I'm not changing this behavior in this patch).

---
diff --git a/arch/powerpc/platforms/cell/smp.c b/arch/powerpc/platforms/cell/smp.c
index efb3964..c0d86e1 100644
--- a/arch/powerpc/platforms/cell/smp.c
+++ b/arch/powerpc/platforms/cell/smp.c
@@ -54,8 +54,8 @@
 #endif
 
 /*
- * The primary thread of each non-boot processor is recorded here before
- * smp init.
+ * The Primary thread of each non-boot processor was started from the OF client
+ * interface by prom_hold_cpus and is spinning on secondary_hold_spinloop.
  */
 static cpumask_t of_spin_map;
 
@@ -208,11 +208,7 @@ void __init smp_init_cell(void)
 	/* Mark threads which are still spinning in hold loops. */
 	if (cpu_has_feature(CPU_FTR_SMT)) {
 		for_each_present_cpu(i) {
-			if (i % 2 == 0)
-				/*
-				 * Even-numbered logical cpus correspond to
-				 * primary threads.
-				 */
+			if (cpu_thread_in_core(i) == 0)
 				cpu_set(i, of_spin_map);
 		}
 	} else {
diff --git a/arch/powerpc/platforms/pseries/smp.c b/arch/powerpc/platforms/pseries/smp.c
index 9d8f8c8..c9337c7 100644
--- a/arch/powerpc/platforms/pseries/smp.c
+++ b/arch/powerpc/platforms/pseries/smp.c
@@ -52,8 +52,8 @@
 
 
 /*
- * The primary thread of each non-boot processor is recorded here before
- * smp init.
+ * The Primary thread of each non-boot processor was started from the OF client
+ * interface by prom_hold_cpus and is spinning on secondary_hold_spinloop.
  */
 static cpumask_t of_spin_map;
 
@@ -191,8 +191,7 @@ static void __devinit smp_pSeries_kick_cpu(int nr)
 static int smp_pSeries_cpu_bootable(unsigned int nr)
 {
 	/* Special case - we inhibit secondary thread startup
-	 * during boot if the user requests it.  Odd-numbered
-	 * cpus are assumed to be secondary threads.
+	 * during boot if the user requests it.
 	 */
 	if (system_state < SYSTEM_RUNNING &&
 	    cpu_has_feature(CPU_FTR_SMT) &&
@@ -229,11 +228,7 @@ static void __init smp_init_pseries(void)
 	/* Mark threads which are still spinning in hold loops. */
 	if (cpu_has_feature(CPU_FTR_SMT)) {
 		for_each_present_cpu(i) { 
-			if (i % 2 == 0)
-				/*
-				 * Even-numbered logical cpus correspond to
-				 * primary threads.
-				 */
+			if (cpu_thread_in_core(i) == 0)
 				cpu_set(i, of_spin_map);
 		}
 	} else {

[RFC] (almost) booting allyesconfig -- please don't poke super-io without request_region

[Milton Miller]

After the following patch to mark the isa region busy and applying a few
patches[1], I was able to kexec boot into an all-yes-config kernel from 
linux-next, with the following KCONFIG_ALLCONFIG file:

# CONFIG_KALLSYMS_EXTRA_PASS is not set
# CONFIG_CRASH_DUMP is not set
CONFIG_PPC_EARLY_DEBUG_RTAS_CONSOLE=y
# CONFIG_NSC_FIR is not set
# CONFIG_SMC_IRCC_FIR is not set
# CONFIG_ALI_FIR is not set
# CONFIG_TCG_NSC is not set
# CONFIG_TCG_ATMEL is not set
# CONFIG_SENSORS_F71805F is not set
# CONFIG_SENSORS_F71882FG is not set
# CONFIG_SENSORS_F75375S is not set
# CONFIG_SENSORS_IT87 is not set
# CONFIG_SENSORS_PC87360 is not set
# CONFIG_SENSORS_PC87427 is not set
# CONFIG_SENSORS_DME1737 is not set
# CONFIG_SENSORS_SMSC47M1 is not set
# CONFIG_SENSORS_SMSC47B397 is not set
# CONFIG_SENSORS_VT1211 is not set
# CONFIG_SENSORS_W83627HF is not set
# CONFIG_SENSORS_W83627EHF is not set

While the first two might not be required, and the third is just
selecting the right platform, it would be nice to get the drivers
to play as well as the rest of the kernel.

The drivers all are for super-io chips, either irda/FIR drivers or hwmon,
and poke at isa ports without checking request_region.

It would be great if these 17 super-io drivers would check for resource
availability before poking at io ports.

[not that I expect this to merge as it, but maybe insert-resource or something]



[1] 3 section layout patches and the MTD DISKONCHIP patch,
see linuxppc-dev for full list


diff --git a/arch/powerpc/platforms/pseries/pci.c b/arch/powerpc/platforms/pseries/pci.c
index 2c6ded2..db54620 100644
--- a/arch/powerpc/platforms/pseries/pci.c
+++ b/arch/powerpc/platforms/pseries/pci.c
@@ -58,8 +58,10 @@ DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, pcibios_name_device);
 
 static void __init pSeries_request_regions(void)
 {
-	if (!isa_io_base)
+	if (!isa_io_base) {
+		request_region(0x0,0x400,"isa");
 		return;
+		}
 
 	request_region(0x20,0x20,"pic1");
 	request_region(0xa0,0x20,"pic2");

powerpc: pseries, cell: use cpu_thread_in_core in smp_init for of_spin_map

[Milton Miller]

Replace a left over % 2 to be a check for the primary thread and
update the comments.

Note: We assume the secondary threads are not spinning, but they are
actually spinning if we start via kexec.  This means that we call rtas to
spin up the secondary threads. If we get a bad return code from we skip
bringing the cpu online, leaving the thread spinning on the paca.  We don't
handle this case in kexec, and will leave the thread wild during another
kexec.

Signed-off-by: Milton Miller <miltonm@bga.com>
---
I added a debug print and manually verified the correct cpumask was
generated on pSeries.  I ran across the identical code in cell by
the grep of System.map.



diff --git a/arch/powerpc/platforms/cell/smp.c b/arch/powerpc/platforms/cell/smp.c
index efb3964..c0d86e1 100644
--- a/arch/powerpc/platforms/cell/smp.c
+++ b/arch/powerpc/platforms/cell/smp.c
@@ -54,8 +54,8 @@
 #endif
 
 /*
- * The primary thread of each non-boot processor is recorded here before
- * smp init.
+ * The Primary thread of each non-boot processor was started from the OF client
+ * interface by prom_hold_cpus and is spinning on secondary_hold_spinloop.
  */
 static cpumask_t of_spin_map;
 
@@ -208,11 +208,7 @@ void __init smp_init_cell(void)
 	/* Mark threads which are still spinning in hold loops. */
 	if (cpu_has_feature(CPU_FTR_SMT)) {
 		for_each_present_cpu(i) {
-			if (i % 2 == 0)
-				/*
-				 * Even-numbered logical cpus correspond to
-				 * primary threads.
-				 */
+			if (cpu_thread_in_core(i) == 0)
 				cpu_set(i, of_spin_map);
 		}
 	} else {
diff --git a/arch/powerpc/platforms/pseries/smp.c b/arch/powerpc/platforms/pseries/smp.c
index 9d8f8c8..c9337c7 100644
--- a/arch/powerpc/platforms/pseries/smp.c
+++ b/arch/powerpc/platforms/pseries/smp.c
@@ -52,8 +52,8 @@
 
 
 /*
- * The primary thread of each non-boot processor is recorded here before
- * smp init.
+ * The Primary thread of each non-boot processor was started from the OF client
+ * interface by prom_hold_cpus and is spinning on secondary_hold_spinloop.
  */
 static cpumask_t of_spin_map;
 
@@ -191,8 +191,7 @@ static void __devinit smp_pSeries_kick_cpu(int nr)
 static int smp_pSeries_cpu_bootable(unsigned int nr)
 {
 	/* Special case - we inhibit secondary thread startup
-	 * during boot if the user requests it.  Odd-numbered
-	 * cpus are assumed to be secondary threads.
+	 * during boot if the user requests it.
 	 */
 	if (system_state < SYSTEM_RUNNING &&
 	    cpu_has_feature(CPU_FTR_SMT) &&
@@ -229,11 +228,7 @@ static void __init smp_init_pseries(void)
 	/* Mark threads which are still spinning in hold loops. */
 	if (cpu_has_feature(CPU_FTR_SMT)) {
 		for_each_present_cpu(i) { 
-			if (i % 2 == 0)
-				/*
-				 * Even-numbered logical cpus correspond to
-				 * primary threads.
-				 */
+			if (cpu_thread_in_core(i) == 0)
 				cpu_set(i, of_spin_map);
 		}
 	} else {