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[RFC v3 07/13] bcma: get CPU clock

To: linux-wireless@vger.kernel.org, zajec5@gmail.com, linux-mips@linux-mips.org
Subject: [RFC v3 07/13] bcma: get CPU clock
From: Hauke Mehrtens <hauke@hauke-m.de>
Date: Thu, 30 Jun 2011 00:11:52 +0200
Cc: mb@bu3sch.de, george@znau.edu.ua, arend@broadcom.com, b43-dev@lists.infradead.org, bernhardloos@googlemail.com, arnd@arndb.de, julian.calaby@gmail.com, sshtylyov@mvista.com, Hauke Mehrtens <hauke@hauke-m.de>
In-reply-to: <1309385518-12097-1-git-send-email-hauke@hauke-m.de>
References: <1309385518-12097-1-git-send-email-hauke@hauke-m.de>
Sender: linux-mips-bounce@linux-mips.org
Add method to return the clock of the CPU. This is needed by the arch
code to calculate the mips_hpt_frequency.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
---
 drivers/bcma/bcma_private.h                 |    3 +
 drivers/bcma/driver_chipcommon_pmu.c        |   87 +++++++++++++++++++++++++++
 drivers/bcma/driver_mips.c                  |   12 ++++
 include/linux/bcma/bcma_driver_chipcommon.h |   35 +++++++++++
 include/linux/bcma/bcma_driver_mips.h       |    1 +
 5 files changed, 138 insertions(+), 0 deletions(-)

diff --git a/drivers/bcma/bcma_private.h b/drivers/bcma/bcma_private.h
index 4597178..d25dedd 100644
--- a/drivers/bcma/bcma_private.h
+++ b/drivers/bcma/bcma_private.h
@@ -29,6 +29,9 @@ void bcma_init_bus(struct bcma_bus *bus);
 /* sprom.c */
 int bcma_sprom_get(struct bcma_bus *bus);
 
+/* driver_chipcommon_pmu.c */
+extern u32 bcma_pmu_get_clockcpu(struct bcma_drv_cc *cc);
+
 /* driver_chipcommon.c */
 #ifdef CONFIG_BCMA_DRIVER_MIPS
 extern int bcma_chipco_serial_init(struct bcma_drv_cc *cc,
diff --git a/drivers/bcma/driver_chipcommon_pmu.c 
b/drivers/bcma/driver_chipcommon_pmu.c
index dd5846b..d9aa9ef 100644
--- a/drivers/bcma/driver_chipcommon_pmu.c
+++ b/drivers/bcma/driver_chipcommon_pmu.c
@@ -11,6 +11,13 @@
 #include "bcma_private.h"
 #include <linux/bcma/bcma.h>
 
+static u32 bcma_chipco_pll_read(struct bcma_drv_cc *cc, u32 offset)
+{
+       bcma_cc_write32(cc, BCMA_CC_PLLCTL_ADDR, offset);
+       bcma_cc_read32(cc, BCMA_CC_PLLCTL_ADDR);
+       return bcma_cc_read32(cc, BCMA_CC_PLLCTL_DATA);
+}
+
 static void bcma_chipco_chipctl_maskset(struct bcma_drv_cc *cc,
                                        u32 offset, u32 mask, u32 set)
 {
@@ -136,3 +143,83 @@ void bcma_pmu_init(struct bcma_drv_cc *cc)
        bcma_pmu_swreg_init(cc);
        bcma_pmu_workarounds(cc);
 }
+
+static u32 bcma_pmu_alp_clock(struct bcma_drv_cc *cc)
+{
+       struct bcma_bus *bus = cc->core->bus;
+
+       switch (bus->chipinfo.id) {
+       case 0x4716:
+       case 0x4748:
+       case 47162:
+               /* always 20Mhz */
+               return 20000 * 1000;
+       default:
+               pr_warn("No ALP clock specified for %04X device, "
+                       "pmu rev. %d, using default %d Hz\n",
+                       bus->chipinfo.id, cc->pmu.rev, BCMA_CC_PMU_ALP_CLOCK);
+       }
+       return BCMA_CC_PMU_ALP_CLOCK;
+}
+
+/* Find the output of the "m" pll divider given pll controls that start with
+ * pllreg "pll0" i.e. 12 for main 6 for phy, 0 for misc.
+ */
+static u32 bcma_pmu_clock(struct bcma_drv_cc *cc, u32 pll0, u32 m)
+{
+       u32 tmp, div, ndiv, p1, p2, fc;
+
+       BUG_ON(!m || m > 4);
+
+       BUG_ON((pll0 & 3) || (pll0 > BCMA_CC_PMU4716_MAINPLL_PLL0));
+
+       tmp = bcma_chipco_pll_read(cc, pll0 + BCMA_CC_PPL_P1P2_OFF);
+       p1 = (tmp & BCMA_CC_PPL_P1_MASK) >> BCMA_CC_PPL_P1_SHIFT;
+       p2 = (tmp & BCMA_CC_PPL_P2_MASK) >> BCMA_CC_PPL_P2_SHIFT;
+
+       tmp = bcma_chipco_pll_read(cc, pll0 + BCMA_CC_PPL_M14_OFF);
+       div = (tmp >> ((m - 1) * BCMA_CC_PPL_MDIV_WIDTH)) &
+               BCMA_CC_PPL_MDIV_MASK;
+
+       tmp = bcma_chipco_pll_read(cc, pll0 + BCMA_CC_PPL_NM5_OFF);
+       ndiv = (tmp & BCMA_CC_PPL_NDIV_MASK) >> BCMA_CC_PPL_NDIV_SHIFT;
+
+       /* Do calculation in Mhz */
+       fc = bcma_pmu_alp_clock(cc) / 1000000;
+       fc = (p1 * ndiv * fc) / p2;
+
+       /* Return clock in Hertz */
+       return (fc / div) * 1000000;
+}
+
+/* query bus clock frequency for PMU-enabled chipcommon */
+u32 bcma_pmu_get_clockcontrol(struct bcma_drv_cc *cc)
+{
+       struct bcma_bus *bus = cc->core->bus;
+
+       switch (bus->chipinfo.id) {
+       case 0x4716:
+       case 0x4748:
+       case 47162:
+               return bcma_pmu_clock(cc, BCMA_CC_PMU4716_MAINPLL_PLL0,
+                                     BCMA_CC_PMU5_MAINPLL_SSB);
+       default:
+               pr_warn("No backplane clock specified for %04X device, "
+                       "pmu rev. %d, using default %d Hz\n",
+                       bus->chipinfo.id, cc->pmu.rev, BCMA_CC_PMU_HT_CLOCK);
+       }
+       return BCMA_CC_PMU_HT_CLOCK;
+}
+
+/* query cpu clock frequency for PMU-enabled chipcommon */
+u32 bcma_pmu_get_clockcpu(struct bcma_drv_cc *cc)
+{
+       struct bcma_bus *bus = cc->core->bus;
+
+       if ((cc->pmu.rev == 5 || cc->pmu.rev == 6 || cc->pmu.rev == 7) &&
+           (bus->chipinfo.id != 0x4319))
+               return bcma_pmu_clock(cc, BCMA_CC_PMU4716_MAINPLL_PLL0,
+                                     BCMA_CC_PMU5_MAINPLL_CPU);
+
+       return bcma_pmu_get_clockcontrol(cc);
+}
diff --git a/drivers/bcma/driver_mips.c b/drivers/bcma/driver_mips.c
index 3989fb9..813f9df 100644
--- a/drivers/bcma/driver_mips.c
+++ b/drivers/bcma/driver_mips.c
@@ -156,6 +156,18 @@ static void bcma_core_mips_dump_irq(struct bcma_bus *bus)
        }
 }
 
+u32 bcma_cpu_clock(struct bcma_drv_mips *mcore)
+{
+       struct bcma_bus *bus = mcore->core->bus;
+
+       if (bus->drv_cc.capabilities & BCMA_CC_CAP_PMU)
+               return bcma_pmu_get_clockcpu(&bus->drv_cc);
+
+       pr_err("No PMU available, need this to get the cpu clock\n");
+       return 0;
+}
+EXPORT_SYMBOL(bcma_cpu_clock);
+
 static void bcma_core_mips_serial_init(struct bcma_drv_mips *mcore)
 {
        struct bcma_bus *bus = mcore->core->bus;
diff --git a/include/linux/bcma/bcma_driver_chipcommon.h 
b/include/linux/bcma/bcma_driver_chipcommon.h
index c036f73..1974ef3 100644
--- a/include/linux/bcma/bcma_driver_chipcommon.h
+++ b/include/linux/bcma/bcma_driver_chipcommon.h
@@ -246,6 +246,41 @@
 #define BCMA_CC_PLLCTL_DATA            0x0664
 #define BCMA_CC_SPROM                  0x0830 /* SPROM beginning */
 
+/* Divider allocation in 4716/47162/5356 */
+#define BCMA_CC_PMU5_MAINPLL_CPU       1
+#define BCMA_CC_PMU5_MAINPLL_MEM       2
+#define BCMA_CC_PMU5_MAINPLL_SSB       3
+
+/* PLL usage in 4716/47162 */
+#define BCMA_CC_PMU4716_MAINPLL_PLL0   12
+
+/* ALP clock on pre-PMU chips */
+#define BCMA_CC_PMU_ALP_CLOCK          20000000
+/* HT clock for systems with PMU-enabled chipcommon */
+#define BCMA_CC_PMU_HT_CLOCK           80000000
+
+/* PMU rev 5 (& 6) */
+#define        BCMA_CC_PPL_P1P2_OFF            0
+#define        BCMA_CC_PPL_P1_MASK             0x0f000000
+#define        BCMA_CC_PPL_P1_SHIFT            24
+#define        BCMA_CC_PPL_P2_MASK             0x00f00000
+#define        BCMA_CC_PPL_P2_SHIFT            20
+#define        BCMA_CC_PPL_M14_OFF             1
+#define        BCMA_CC_PPL_MDIV_MASK           0x000000ff
+#define        BCMA_CC_PPL_MDIV_WIDTH          8
+#define        BCMA_CC_PPL_NM5_OFF             2
+#define        BCMA_CC_PPL_NDIV_MASK           0xfff00000
+#define        BCMA_CC_PPL_NDIV_SHIFT          20
+#define        BCMA_CC_PPL_FMAB_OFF            3
+#define        BCMA_CC_PPL_MRAT_MASK           0xf0000000
+#define        BCMA_CC_PPL_MRAT_SHIFT          28
+#define        BCMA_CC_PPL_ABRAT_MASK          0x08000000
+#define        BCMA_CC_PPL_ABRAT_SHIFT         27
+#define        BCMA_CC_PPL_FDIV_MASK           0x07ffffff
+#define        BCMA_CC_PPL_PLLCTL_OFF          4
+#define        BCMA_CC_PPL_PCHI_OFF            5
+#define        BCMA_CC_PPL_PCHI_MASK           0x0000003f
+
 /* Data for the PMU, if available.
  * Check availability with ((struct bcma_chipcommon)->capabilities & 
BCMA_CC_CAP_PMU)
  */
diff --git a/include/linux/bcma/bcma_driver_mips.h 
b/include/linux/bcma/bcma_driver_mips.h
index 13b44c2..402af95 100644
--- a/include/linux/bcma/bcma_driver_mips.h
+++ b/include/linux/bcma/bcma_driver_mips.h
@@ -54,6 +54,7 @@ struct bcma_drv_mips {
 };
 
 extern void bcma_core_mips_init(struct bcma_drv_mips *mcore);
+extern u32 bcma_cpu_clock(struct bcma_drv_mips *mcore);
 
 extern unsigned int bcma_core_mips_irq(struct bcma_device *dev);
 
-- 
1.7.4.1


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