[PATCH 2/6] mips: bmips: rework and cache CBR addr handling

[Christian Marangi <ansuelsmth@gmail.com>]

Rework the handling of the CBR address and cache it. This address
doesn't chance and can be cache instead of calling the register every
time.

This is in preparation of permitting to tweak the CBR address in DT with
broken SoC or bootloader.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
---
 arch/mips/bmips/dma.c         |  7 +++----
 arch/mips/bmips/setup.c       |  6 +++++-
 arch/mips/include/asm/bmips.h |  1 +
 arch/mips/kernel/smp-bmips.c  | 31 ++++++++++++++-----------------
 4 files changed, 23 insertions(+), 22 deletions(-)

diff --git a/arch/mips/bmips/dma.c b/arch/mips/bmips/dma.c
index 3779e7855bd7..799cc3e12fc3 100644
--- a/arch/mips/bmips/dma.c
+++ b/arch/mips/bmips/dma.c
@@ -9,7 +9,6 @@ bool bmips_rac_flush_disable;
 
 void arch_sync_dma_for_cpu_all(void)
 {
-	void __iomem *cbr = BMIPS_GET_CBR();
 	u32 cfg;
 
 	if (boot_cpu_type() != CPU_BMIPS3300 &&
@@ -21,7 +20,7 @@ void arch_sync_dma_for_cpu_all(void)
 		return;
 
 	/* Flush stale data out of the readahead cache */
-	cfg = __raw_readl(cbr + BMIPS_RAC_CONFIG);
-	__raw_writel(cfg | 0x100, cbr + BMIPS_RAC_CONFIG);
-	__raw_readl(cbr + BMIPS_RAC_CONFIG);
+	cfg = __raw_readl(bmips_cbr_addr + BMIPS_RAC_CONFIG);
+	__raw_writel(cfg | 0x100, bmips_cbr_addr + BMIPS_RAC_CONFIG);
+	__raw_readl(bmips_cbr_addr + BMIPS_RAC_CONFIG);
 }
diff --git a/arch/mips/bmips/setup.c b/arch/mips/bmips/setup.c
index 66a8ba19c287..18561d426f89 100644
--- a/arch/mips/bmips/setup.c
+++ b/arch/mips/bmips/setup.c
@@ -34,6 +34,8 @@
 #define REG_BCM6328_OTP		((void __iomem *)CKSEG1ADDR(0x1000062c))
 #define BCM6328_TP1_DISABLED	BIT(9)
 
+/* CBR addr doesn't change and we can cache it */
+void __iomem *bmips_cbr_addr;
 extern bool bmips_rac_flush_disable;
 
 static const unsigned long kbase = VMLINUX_LOAD_ADDRESS & 0xfff00000;
@@ -111,7 +113,7 @@ static void bcm6358_quirks(void)
 	 * because the bootloader is not initializing it properly.
 	 */
 	bmips_rac_flush_disable = !!(read_c0_brcm_cmt_local() & (1 << 31)) ||
-				  !!BMIPS_GET_CBR();
+				  !!bmips_cbr_addr;
 }
 
 static void bcm6368_quirks(void)
@@ -144,6 +146,8 @@ static void __init bmips_init_cfe(void)
 
 void __init prom_init(void)
 {
+	/* Cache CBR addr before CPU/DMA setup */
+	bmips_cbr_addr = BMIPS_GET_CBR();
 	bmips_init_cfe();
 	bmips_cpu_setup();
 	register_bmips_smp_ops();
diff --git a/arch/mips/include/asm/bmips.h b/arch/mips/include/asm/bmips.h
index 581a6a3c66e4..3a1cdfddb987 100644
--- a/arch/mips/include/asm/bmips.h
+++ b/arch/mips/include/asm/bmips.h
@@ -81,6 +81,7 @@ extern char bmips_smp_movevec[];
 extern char bmips_smp_int_vec[];
 extern char bmips_smp_int_vec_end[];
 
+extern void __iomem *bmips_cbr_addr;
 extern int bmips_smp_enabled;
 extern int bmips_cpu_offset;
 extern cpumask_t bmips_booted_mask;
diff --git a/arch/mips/kernel/smp-bmips.c b/arch/mips/kernel/smp-bmips.c
index b3dbf9ecb0d6..6048c471b5ee 100644
--- a/arch/mips/kernel/smp-bmips.c
+++ b/arch/mips/kernel/smp-bmips.c
@@ -518,14 +518,12 @@ static void bmips_set_reset_vec(int cpu, u32 val)
 		info.val = val;
 		bmips_set_reset_vec_remote(&info);
 	} else {
-		void __iomem *cbr = BMIPS_GET_CBR();
-
 		if (cpu == 0)
-			__raw_writel(val, cbr + BMIPS_RELO_VECTOR_CONTROL_0);
+			__raw_writel(val, bmips_cbr_addr + BMIPS_RELO_VECTOR_CONTROL_0);
 		else {
 			if (current_cpu_type() != CPU_BMIPS4380)
 				return;
-			__raw_writel(val, cbr + BMIPS_RELO_VECTOR_CONTROL_1);
+			__raw_writel(val, bmips_cbr_addr + BMIPS_RELO_VECTOR_CONTROL_1);
 		}
 	}
 	__sync();
@@ -591,7 +589,6 @@ asmlinkage void __weak plat_wired_tlb_setup(void)
 
 void bmips_cpu_setup(void)
 {
-	void __iomem __maybe_unused *cbr = BMIPS_GET_CBR();
 	u32 __maybe_unused cfg;
 
 	switch (current_cpu_type()) {
@@ -607,17 +604,17 @@ void bmips_cpu_setup(void)
 		clear_c0_brcm_reset(BIT(16));
 
 		/* Flush and enable RAC */
-		cfg = __raw_readl(cbr + BMIPS_RAC_CONFIG);
-		__raw_writel(cfg | 0x100, cbr + BMIPS_RAC_CONFIG);
-		__raw_readl(cbr + BMIPS_RAC_CONFIG);
+		cfg = __raw_readl(bmips_cbr_addr + BMIPS_RAC_CONFIG);
+		__raw_writel(cfg | 0x100, bmips_cbr_addr + BMIPS_RAC_CONFIG);
+		__raw_readl(bmips_cbr_addr + BMIPS_RAC_CONFIG);
 
-		cfg = __raw_readl(cbr + BMIPS_RAC_CONFIG);
-		__raw_writel(cfg | 0xf, cbr + BMIPS_RAC_CONFIG);
-		__raw_readl(cbr + BMIPS_RAC_CONFIG);
+		cfg = __raw_readl(bmips_cbr_addr + BMIPS_RAC_CONFIG);
+		__raw_writel(cfg | 0xf, bmips_cbr_addr + BMIPS_RAC_CONFIG);
+		__raw_readl(bmips_cbr_addr + BMIPS_RAC_CONFIG);
 
-		cfg = __raw_readl(cbr + BMIPS_RAC_ADDRESS_RANGE);
-		__raw_writel(cfg | 0x0fff0000, cbr + BMIPS_RAC_ADDRESS_RANGE);
-		__raw_readl(cbr + BMIPS_RAC_ADDRESS_RANGE);
+		cfg = __raw_readl(bmips_cbr_addr + BMIPS_RAC_ADDRESS_RANGE);
+		__raw_writel(cfg | 0x0fff0000, bmips_cbr_addr + BMIPS_RAC_ADDRESS_RANGE);
+		__raw_readl(bmips_cbr_addr + BMIPS_RAC_ADDRESS_RANGE);
 		break;
 
 	case CPU_BMIPS4380:
@@ -627,9 +624,9 @@ void bmips_cpu_setup(void)
 		case 0x2a042:
 		case 0x2a044:
 		case 0x2a060:
-			cfg = __raw_readl(cbr + BMIPS_L2_CONFIG);
-			__raw_writel(cfg & ~0x07000000, cbr + BMIPS_L2_CONFIG);
-			__raw_readl(cbr + BMIPS_L2_CONFIG);
+			cfg = __raw_readl(bmips_cbr_addr + BMIPS_L2_CONFIG);
+			__raw_writel(cfg & ~0x07000000, bmips_cbr_addr + BMIPS_L2_CONFIG);
+			__raw_readl(bmips_cbr_addr + BMIPS_L2_CONFIG);
 		}
 
 		/* clear BHTD to enable branch history table */
-- 
2.43.0