[PATCH 1/8] MIPS: Octeon: Add octeon_io_clk_delay() function.

From: David Daney
Date: Tue Aug 21 2012 - 14:46:42 EST


From: David Daney <ddaney@xxxxxxxxxxxxxxxxxx>

Also cleanup and fix octeon_init_cvmcount()

Signed-off-by: David Daney <ddaney@xxxxxxxxxxxxxxxxxx>
---
arch/mips/cavium-octeon/csrc-octeon.c | 93 ++++++++++++++++++++++++-----------
arch/mips/cavium-octeon/setup.c | 3 +-
arch/mips/include/asm/octeon/octeon.h | 1 +
3 files changed, 66 insertions(+), 31 deletions(-)

diff --git a/arch/mips/cavium-octeon/csrc-octeon.c b/arch/mips/cavium-octeon/csrc-octeon.c
index ce6483a..0219395 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 919b0fb..04dd8ff 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;
diff --git a/arch/mips/include/asm/octeon/octeon.h b/arch/mips/include/asm/octeon/octeon.h
index a31288e..96e58a5 100644
--- a/arch/mips/include/asm/octeon/octeon.h
+++ b/arch/mips/include/asm/octeon/octeon.h
@@ -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
--
1.7.11.4

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