ARM: tegra: Use a function to get the chip ID

Instead of using a simple variable access to get at the Tegra chip ID,
use a function so that we can run additional code. This can be used to
determine where the chip ID is being accessed without being available.
That in turn will be handy for resolving boot sequence dependencies in
order to convert more code to regular initcalls rather than a sequence
fixed by Tegra SoC setup code.

Signed-off-by: Thierry Reding <treding@nvidia.com>

1 files changed, 13 insertions, 6 deletions

diff --git a/arch/arm/mach-tegra/fuse.c b/arch/arm/mach-tegra/fuse.c
index af28303..b22e76a 100644
--- a/arch/arm/mach-tegra/fuse.c
+++ b/arch/arm/mach-tegra/fuse.c
@@ -51,7 +51,6 @@
 int tegra_sku_id;
 int tegra_cpu_process_id;
 int tegra_core_process_id;
-int tegra_chip_id;
 int tegra_cpu_speedo_id;		/* only exist in Tegra30 and later */
 int tegra_soc_speedo_id;
 enum tegra_revision tegra_revision;
@@ -124,7 +123,7 @@ static enum tegra_revision tegra_get_revision(u32 id)
 	case 2:
 		return TEGRA_REVISION_A02;
 	case 3:
-		if (tegra_chip_id == TEGRA20 &&
+		if (tegra_get_chip_id() == TEGRA20 &&
 			(tegra_spare_fuse(18) || tegra_spare_fuse(19)))
 			return TEGRA_REVISION_A03p;
 		else
@@ -155,6 +154,13 @@ u32 tegra_read_chipid(void)
 	return readl_relaxed(IO_ADDRESS(TEGRA_APB_MISC_BASE) + 0x804);
 }
 
+u8 tegra_get_chip_id(void)
+{
+	u32 id = tegra_read_chipid();
+
+	return (id >> 8) & 0xff;
+}
+
 static void __init tegra20_fuse_init_randomness(void)
 {
 	u32 randomness[2];
@@ -185,6 +191,7 @@ void __init tegra_init_fuse(void)
 {
 	u32 id;
 	u32 randomness[5];
+	u8 chip_id;
 
 	u32 reg = readl(IO_ADDRESS(TEGRA_CLK_RESET_BASE + 0x48));
 	reg |= 1 << 28;
@@ -209,9 +216,9 @@ void __init tegra_init_fuse(void)
 
 	id = tegra_read_chipid();
 	randomness[2] = id;
-	tegra_chip_id = (id >> 8) & 0xff;
+	chip_id = (id >> 8) & 0xff;
 
-	switch (tegra_chip_id) {
+	switch (chip_id) {
 	case TEGRA20:
 		tegra_fuse_spare_bit = TEGRA20_FUSE_SPARE_BIT;
 		tegra_init_speedo_data = &tegra20_init_speedo_data;
@@ -224,7 +231,7 @@ void __init tegra_init_fuse(void)
 		tegra_init_speedo_data = &tegra114_init_speedo_data;
 		break;
 	default:
-		pr_warn("Tegra: unknown chip id %d\n", tegra_chip_id);
+		pr_warn("Tegra: unknown chip id %d\n", chip_id);
 		tegra_fuse_spare_bit = TEGRA20_FUSE_SPARE_BIT;
 		tegra_init_speedo_data = &tegra_get_process_id;
 	}
@@ -235,7 +242,7 @@ void __init tegra_init_fuse(void)
 	randomness[4] = (tegra_cpu_speedo_id << 16) | tegra_soc_speedo_id;
 
 	add_device_randomness(randomness, sizeof(randomness));
-	switch (tegra_chip_id) {
+	switch (chip_id) {
 	case TEGRA20:
 		tegra20_fuse_init_randomness();
 		break;