ARM: shmobile: Consolidate early delay setup code

From: Magnus Damm <[email protected]>

Introduce shmobile_init_delay() that gets CPU specific parameters from DT and sets up the early delay from there. This allows us to both remove frequency information from the C code and consolidate existing code.

Signed-off-by Magnus Damm <[email protected]>

---

 arch/arm/mach-shmobile/include/mach/common.h |    1 
 arch/arm/mach-shmobile/timer.c               |   28 ++++++++++++++++++++++++++
 2 files changed, 29 insertions(+)

arch/arm/mach-shmobile/include/mach/common.h +1 -0

@@ -4,6 +4,7 @@
 extern void shmobile_earlytimer_init(void);
 extern void shmobile_setup_delay(unsigned int max_cpu_core_mhz,
 			 unsigned int mult, unsigned int div);
+extern void shmobile_init_delay(void);
 struct twd_local_timer;
 extern void shmobile_setup_console(void);
 extern void shmobile_boot_vector(void);

arch/arm/mach-shmobile/timer.c +28 -0

@@ -21,6 +21,7 @@
 #include <linux/platform_device.h>
 #include <linux/clocksource.h>
 #include <linux/delay.h>
+#include <linux/of_address.h>
 
 void __init shmobile_setup_delay(unsigned int max_cpu_core_mhz,
 				 unsigned int mult, unsigned int div)

@@ -39,6 +40,33 @@ void __init shmobile_setup_delay(unsigne
 		preset_lpj = max_cpu_core_mhz * value;
 }
 
+void __init shmobile_init_delay(void)
+{
+	struct device_node *np, *parent;
+	u32 max_freq, freq;
+
+	max_freq = 0;
+
+	parent = of_find_node_by_path("/cpus");
+	if (parent) {
+		for_each_child_of_node(parent, np) {
+			if (!of_property_read_u32(np, "clock-frequency", &freq))
+				max_freq = max(max_freq, freq);
+		}
+		of_node_put(parent);
+	}
+
+	if (max_freq) {
+		if (of_find_compatible_node(NULL, NULL, "arm,cortex-a8"))
+			shmobile_setup_delay(max_freq, 1, 3);
+		else if (of_find_compatible_node(NULL, NULL, "arm,cortex-a9"))
+			shmobile_setup_delay(max_freq, 1, 3);
+		else if (of_find_compatible_node(NULL, NULL, "arm,cortex-a15"))
+			if (!IS_ENABLED(CONFIG_ARM_ARCH_TIMER))
+				shmobile_setup_delay(max_freq, 2, 4);
+	}
+}
+
 static void __init shmobile_late_time_init(void)
 {
 	/*

Quoted 7 lines · Magnus Damm

From: Magnus Damm <[email protected]>

Introduce shmobile_init_delay() that gets CPU specific parameters from DT and sets up the early delay from there. This allows us to both remove frequency information from the C code and consolidate existing code.

Quoted 1 line

Signed-off-by Magnus Damm <[email protected]>

Hi Magnus,

I am holding off on this one until the rest of the series is finalised.

Hi Magnus,

arch/arm/mach-shmobile/setup-rcar-gen2.c 2014-06-09 21:01:33.000000000 +0900

Quoted 8 lines · Magnus Damm

arch/arm/mach-shmobile/setup-rcar-gen2.c 2014-06-09 21:01:33.000000000 +0900 renamed from arch/arm/mach-shmobile/setup-rcar-gen2.c +4 -0

 
+static int __init rcar_gen2_scan_mem(unsigned long node, const char *uname,
+                                    int depth, void *data)
+{
 
+       u64 lpae_start = (u64)1 << 32;

Casts are evil:

1ULL << 32

(I hope one day gcc will gain a "-Wcast" option, so we can easily find and
inspect all casts, as C-style casts are much more difficult to grep for than C++-style casts).

arch/arm/mach-shmobile/setup-rcar-gen2.c 2014-06-09 21:01:33.000000000 +0900

Quoted 8 lines

arch/arm/mach-shmobile/setup-rcar-gen2.c 2014-06-09 21:01:33.000000000 +0900 renamed from arch/arm/mach-shmobile/setup-rcar-gen2.c +8 -0

+       /* We are scanning "memory" nodes only */
+       if (type = NULL) {
+               /*
+                * The longtrail doesn't have a device_type on the
+                * /memory node, so look for the node called /memory@0.
+                */
+               if (depth != 1 || strcmp(uname, "memory@0") != 0)
+                       return 0;

AFAIK Open Firmware in the LongTrail does not support plugging in ARM CPUs in its PPC 603e/604e-compatible CPU socket ;-)

Quoted 4 lines

arch/arm/mach-shmobile/setup-rcar-gen2.c 2014-06-09 21:01:33.000000000 +0900 renamed from arch/arm/mach-shmobile/setup-rcar-gen2.c +4 -0

+struct cma *rcar_gen2_dma_contiguous;
+
+void __init rcar_gen2_reserve(void)
+{

arch/arm/mach-shmobile/setup-rcar-gen2.c 2014-06-09 21:01:33.000000000 +0900

Quoted 5 lines

arch/arm/mach-shmobile/setup-rcar-gen2.c 2014-06-09 21:01:33.000000000 +0900 renamed from arch/arm/mach-shmobile/setup-rcar-gen2.c +5 -0

+#ifdef CONFIG_DMA_CMA
+       if (mrc.size)
+               dma_contiguous_reserve_area(mrc.size, mrc.base, 0,
+                                           &rcar_gen2_dma_contiguous);
+#endif

I assume one day rcar_gen2_dma_contiguous will become used?

Hi Geert,

Thanks for your feedback!

Quoted 12 lines · Geert Uytterhoeven

Hi Magnus,

arch/arm/mach-shmobile/setup-rcar-gen2.c 2014-06-09 21:01:33.000000000 +0900

Quoted 8 lines · Magnus Damm

arch/arm/mach-shmobile/setup-rcar-gen2.c 2014-06-09 21:01:33.000000000 +0900 renamed from arch/arm/mach-shmobile/setup-rcar-gen2.c +4 -0

 
+static int __init rcar_gen2_scan_mem(unsigned long node, const char *uname,
+                                    int depth, void *data)
+{
 
+       u64 lpae_start = (u64)1 << 32;

Quoted 7 lines

Casts are evil:

1ULL << 32

(I hope one day gcc will gain a "-Wcast" option, so we can easily find and
inspect all casts, as C-style casts are much more difficult to grep for than C++-style casts).

Oh, right, I totally forgot I added that one. =)

Quoted 11 lines

arch/arm/mach-shmobile/setup-rcar-gen2.c 2014-06-09 21:01:33.000000000 +0900

Quoted 8 lines

arch/arm/mach-shmobile/setup-rcar-gen2.c 2014-06-09 21:01:33.000000000 +0900 renamed from arch/arm/mach-shmobile/setup-rcar-gen2.c +8 -0

+       /* We are scanning "memory" nodes only */
+       if (type = NULL) {
+               /*
+                * The longtrail doesn't have a device_type on the
+                * /memory node, so look for the node called /memory@0.
+                */
+               if (depth != 1 || strcmp(uname, "memory@0") != 0)
+                       return 0;

AFAIK Open Firmware in the LongTrail does not support plugging in ARM CPUs in its PPC 603e/604e-compatible CPU socket ;-)

You never know - anything is possible with DT. =)

But yes, I get your point - will clean up.

Quoted 5 lines

Quoted 4 lines

arch/arm/mach-shmobile/setup-rcar-gen2.c 2014-06-09 21:01:33.000000000 +0900 renamed from arch/arm/mach-shmobile/setup-rcar-gen2.c +4 -0

+struct cma *rcar_gen2_dma_contiguous;
+
+void __init rcar_gen2_reserve(void)
+{

Quoted 7 lines

arch/arm/mach-shmobile/setup-rcar-gen2.c 2014-06-09 21:01:33.000000000 +0900

Quoted 5 lines

arch/arm/mach-shmobile/setup-rcar-gen2.c 2014-06-09 21:01:33.000000000 +0900 renamed from arch/arm/mach-shmobile/setup-rcar-gen2.c +5 -0

+#ifdef CONFIG_DMA_CMA
+       if (mrc.size)
+               dma_contiguous_reserve_area(mrc.size, mrc.base, 0,
+                                           &rcar_gen2_dma_contiguous);
+#endif

I assume one day rcar_gen2_dma_contiguous will become used?

That's the idea, yes!

Since Simon kindly queued this up already I will submit an incremental fix to deal with the issues that you pointed out.