ARCv2: IOC: refactor the IOC and SLC operations into own functions

 - Move IOC setup into arc_ioc_setup()
 - Move SLC disabling into arc_slc_disable()

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

2 files changed, 48 insertions, 22 deletions

diff --git a/arch/arc/include/asm/cache.h b/arch/arc/include/asm/cache.h
index b3410ff6a62d..5f924a1024fa 100644
--- a/arch/arc/include/asm/cache.h
+++ b/arch/arc/include/asm/cache.h
@@ -92,8 +92,8 @@ extern unsigned long perip_base, perip_end;
 #define ARC_REG_SLC_RGN_END     0x916
 
 /* Bit val in SLC_CONTROL */
+#define SLC_CTRL_DIS            0x001
 #define SLC_CTRL_IM             0x040
-#define SLC_CTRL_DISABLE        0x001
 #define SLC_CTRL_BUSY           0x100
 #define SLC_CTRL_RGN_OP_INV     0x200
 
diff --git a/arch/arc/mm/cache.c b/arch/arc/mm/cache.c
index 6d98e1d57a18..2c36370a1689 100644
--- a/arch/arc/mm/cache.c
+++ b/arch/arc/mm/cache.c
@@ -601,6 +601,40 @@ noinline void slc_op(phys_addr_t paddr, unsigned long sz, const int op)
 #endif
 }
 
+noinline static void slc_entire_op(const int op)
+{
+        unsigned int ctrl, r = ARC_REG_SLC_CTRL;
+
+        ctrl = read_aux_reg(r);
+
+        if (!(op & OP_FLUSH))           /* i.e. OP_INV */
+                ctrl &= ~SLC_CTRL_IM;   /* clear IM: Disable flush before Inv */
+        else
+                ctrl |= SLC_CTRL_IM;
+
+        write_aux_reg(r, ctrl);
+
+        write_aux_reg(ARC_REG_SLC_INVALIDATE, 1);
+
+        /* Important to wait for flush to complete */
+        while (read_aux_reg(r) & SLC_CTRL_BUSY);
+}
+
+static inline void arc_slc_disable(void)
+{
+        const int r = ARC_REG_SLC_CTRL;
+
+        slc_entire_op(OP_FLUSH_N_INV);
+        write_aux_reg(r, read_aux_reg(r) | SLC_CTRL_DIS);
+}
+
+static inline void arc_slc_enable(void)
+{
+        const int r = ARC_REG_SLC_CTRL;
+
+        write_aux_reg(r, read_aux_reg(r) & ~SLC_CTRL_DIS);
+}
+
 /***********************************************************
  * Exported APIs
  */
@@ -927,6 +961,14 @@ SYSCALL_DEFINE3(cacheflush, uint32_t, start, uint32_t, sz, uint32_t, flags)
         return 0;
 }
 
+noinline void arc_ioc_setup(void)
+{
+        write_aux_reg(ARC_REG_IO_COH_AP0_BASE, 0x80000);
+        write_aux_reg(ARC_REG_IO_COH_AP0_SIZE, 0x11);
+        write_aux_reg(ARC_REG_IO_COH_PARTIAL, 1);
+        write_aux_reg(ARC_REG_IO_COH_ENABLE, 1);
+}
+
 void arc_cache_init(void)
 {
         unsigned int __maybe_unused cpu = smp_processor_id();
@@ -989,30 +1031,14 @@ void arc_cache_init(void)
                 }
         }
 
-        if (is_isa_arcv2() && l2_line_sz && !slc_enable) {
-
-                /* IM set : flush before invalidate */
-                write_aux_reg(ARC_REG_SLC_CTRL,
-                        read_aux_reg(ARC_REG_SLC_CTRL) | SLC_CTRL_IM);
+        /* Note that SLC disable not formally supported till HS 3.0 */
+        if (is_isa_arcv2() && l2_line_sz && !slc_enable)
+                arc_slc_disable();
 
-                write_aux_reg(ARC_REG_SLC_INVALIDATE, 1);
-
-                /* Important to wait for flush to complete */
-                while (read_aux_reg(ARC_REG_SLC_CTRL) & SLC_CTRL_BUSY);
-                write_aux_reg(ARC_REG_SLC_CTRL,
-                        read_aux_reg(ARC_REG_SLC_CTRL) | SLC_CTRL_DISABLE);
-        }
+        if (is_isa_arcv2() && ioc_enable)
+                arc_ioc_setup();
 
         if (is_isa_arcv2() && ioc_enable) {
-                /* IO coherency base - 0x8z */
-                write_aux_reg(ARC_REG_IO_COH_AP0_BASE, 0x80000);
-                /* IO coherency aperture size - 512Mb: 0x8z-0xAz */
-                write_aux_reg(ARC_REG_IO_COH_AP0_SIZE, 0x11);
-                /* Enable partial writes */
-                write_aux_reg(ARC_REG_IO_COH_PARTIAL, 1);
-                /* Enable IO coherency */
-                write_aux_reg(ARC_REG_IO_COH_ENABLE, 1);
-
                 __dma_cache_wback_inv = __dma_cache_wback_inv_ioc;
                 __dma_cache_inv = __dma_cache_inv_ioc;
                 __dma_cache_wback = __dma_cache_wback_ioc;