MIPS: Octeon: Add octeon_io_clk_delay() function.

Also cleanup and fix octeon_init_cvmcount()

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Acked-by: David S. Miller <davem@davemloft.net>

2 files changed, 65 insertions, 31 deletions

diff --git a/arch/mips/cavium-octeon/csrc-octeon.c b/arch/mips/cavium-octeon/csrc-octeon.c
index ce6483a9302a..02193953eb9e 100644
--- a/arch/mips/cavium-octeon/csrc-octeon.c
+++ b/arch/mips/cavium-octeon/csrc-octeon.c
@@ -4,7 +4,7 @@
  * for more details.
  *
  * Copyright (C) 2007 by Ralf Baechle
- * Copyright (C) 2009, 2010 Cavium Networks, Inc.
+ * Copyright (C) 2009, 2012 Cavium, Inc.
  */
 #include <linux/clocksource.h>
 #include <linux/export.h>
@@ -18,6 +18,33 @@
 #include <asm/octeon/cvmx-ipd-defs.h>
 #include <asm/octeon/cvmx-mio-defs.h>
 
+
+static u64 f;
+static u64 rdiv;
+static u64 sdiv;
+static u64 octeon_udelay_factor;
+static u64 octeon_ndelay_factor;
+
+void __init octeon_setup_delays(void)
+{
+        octeon_udelay_factor = octeon_get_clock_rate() / 1000000;
+        /*
+         * For __ndelay we divide by 2^16, so the factor is multiplied
+         * by the same amount.
+         */
+        octeon_ndelay_factor = (octeon_udelay_factor * 0x10000ull) / 1000ull;
+
+        preset_lpj = octeon_get_clock_rate() / HZ;
+
+        if (current_cpu_type() == CPU_CAVIUM_OCTEON2) {
+                union cvmx_mio_rst_boot rst_boot;
+                rst_boot.u64 = cvmx_read_csr(CVMX_MIO_RST_BOOT);
+                rdiv = rst_boot.s.c_mul;        /* CPU clock */
+                sdiv = rst_boot.s.pnr_mul;      /* I/O clock */
+                f = (0x8000000000000000ull / sdiv) * 2;
+        }
+}
+
 /*
  * Set the current core's cvmcount counter to the value of the
  * IPD_CLK_COUNT.  We do this on all cores as they are brought
@@ -30,17 +57,6 @@ void octeon_init_cvmcount(void)
 {
         unsigned long flags;
         unsigned loops = 2;
-        u64 f = 0;
-        u64 rdiv = 0;
-        u64 sdiv = 0;
-        if (current_cpu_type() == CPU_CAVIUM_OCTEON2) {
-                union cvmx_mio_rst_boot rst_boot;
-                rst_boot.u64 = cvmx_read_csr(CVMX_MIO_RST_BOOT);
-                rdiv = rst_boot.s.c_mul;        /* CPU clock */
-                sdiv = rst_boot.s.pnr_mul;      /* I/O clock */
-                f = (0x8000000000000000ull / sdiv) * 2;
-        }
-
 
         /* Clobber loops so GCC will not unroll the following while loop. */
         asm("" : "+r" (loops));
@@ -57,9 +73,9 @@ void octeon_init_cvmcount(void)
                         if (f != 0) {
                                 asm("dmultu\t%[cnt],%[f]\n\t"
                                     "mfhi\t%[cnt]"
-                                    : [cnt] "+r" (ipd_clk_count),
-                                      [f] "=r" (f)
-                                    : : "hi", "lo");
+                                    : [cnt] "+r" (ipd_clk_count)
+                                    : [f] "r" (f)
+                                    : "hi", "lo");
                         }
                 }
                 write_c0_cvmcount(ipd_clk_count);
@@ -109,21 +125,6 @@ void __init plat_time_init(void)
         clocksource_register_hz(&clocksource_mips, octeon_get_clock_rate());
 }
 
-static u64 octeon_udelay_factor;
-static u64 octeon_ndelay_factor;
-
-void __init octeon_setup_delays(void)
-{
-        octeon_udelay_factor = octeon_get_clock_rate() / 1000000;
-        /*
-         * For __ndelay we divide by 2^16, so the factor is multiplied
-         * by the same amount.
-         */
-        octeon_ndelay_factor = (octeon_udelay_factor * 0x10000ull) / 1000ull;
-
-        preset_lpj = octeon_get_clock_rate() / HZ;
-}
-
 void __udelay(unsigned long us)
 {
         u64 cur, end, inc;
@@ -163,3 +164,35 @@ void __delay(unsigned long loops)
                 cur = read_c0_cvmcount();
 }
 EXPORT_SYMBOL(__delay);
+
+
+/**
+ * octeon_io_clk_delay - wait for a given number of io clock cycles to pass.
+ *
+ * We scale the wait by the clock ratio, and then wait for the
+ * corresponding number of core clocks.
+ *
+ * @count: The number of clocks to wait.
+ */
+void octeon_io_clk_delay(unsigned long count)
+{
+        u64 cur, end;
+
+        cur = read_c0_cvmcount();
+        if (rdiv != 0) {
+                end = count * rdiv;
+                if (f != 0) {
+                        asm("dmultu\t%[cnt],%[f]\n\t"
+                                "mfhi\t%[cnt]"
+                                : [cnt] "+r" (end)
+                                : [f] "r" (f)
+                                : "hi", "lo");
+                }
+                end = cur + end;
+        } else {
+                end = cur + count;
+        }
+        while (end > cur)
+                cur = read_c0_cvmcount();
+}
+EXPORT_SYMBOL(octeon_io_clk_delay);
diff --git a/arch/mips/cavium-octeon/setup.c b/arch/mips/cavium-octeon/setup.c
index 919b0fb7bb1a..04dd8ff0e0d8 100644
--- a/arch/mips/cavium-octeon/setup.c
+++ b/arch/mips/cavium-octeon/setup.c
@@ -548,6 +548,8 @@ void __init prom_init(void)
         }
 #endif
 
+        octeon_setup_delays();
+
         /*
          * BIST should always be enabled when doing a soft reset. L2
          * Cache locking for instance is not cleared unless BIST is
@@ -611,7 +613,6 @@ void __init prom_init(void)
         mips_hpt_frequency = octeon_get_clock_rate();
 
         octeon_init_cvmcount();
-        octeon_setup_delays();
 
         _machine_restart = octeon_restart;
         _machine_halt = octeon_halt;