MIPS: Octeon: Add octeon_io_clk_delay() function.
authorDavid Daney <ddaney@caviumnetworks.com>
Tue, 21 Aug 2012 18:45:05 +0000 (11:45 -0700)
committerDavid Daney <david.daney@cavium.com>
Fri, 31 Aug 2012 18:48:48 +0000 (11:48 -0700)
Also cleanup and fix octeon_init_cvmcount()

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Acked-by: David S. Miller <davem@davemloft.net>
arch/mips/cavium-octeon/csrc-octeon.c
arch/mips/cavium-octeon/setup.c
arch/mips/include/asm/octeon/octeon.h

index ce6483a..0219395 100644 (file)
@@ -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>
 #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);
index 919b0fb..04dd8ff 100644 (file)
@@ -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;
index 1e2486e..712f6b7 100644 (file)
@@ -52,6 +52,7 @@ extern asmlinkage void octeon_cop2_restore(struct octeon_cop2_state *task);
 
 extern void octeon_init_cvmcount(void);
 extern void octeon_setup_delays(void);
+extern void octeon_io_clk_delay(unsigned long);
 
 #define OCTEON_ARGV_MAX_ARGS   64
 #define OCTOEN_SERIAL_LEN      20