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author | Gregory Nutt <gnutt@nuttx.org> | 2015-01-09 14:10:31 -0600 |
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committer | Gregory Nutt <gnutt@nuttx.org> | 2015-01-09 14:10:31 -0600 |
commit | 0e6f04e5d5d6ebf16ae866f750a538c5ab4ba448 (patch) | |
tree | 23fa27ca14a201f46af735093c8d40d83ce02755 /nuttx/arch | |
parent | b5ae1a42054b0d3c83da32c7a1652e806b69609e (diff) | |
download | px4-nuttx-0e6f04e5d5d6ebf16ae866f750a538c5ab4ba448.tar.gz px4-nuttx-0e6f04e5d5d6ebf16ae866f750a538c5ab4ba448.tar.bz2 px4-nuttx-0e6f04e5d5d6ebf16ae866f750a538c5ab4ba448.zip |
Tive System Control: Add logic to configure the alternatie clock source (ALTCLK). Needed by the Tiva timer module
Diffstat (limited to 'nuttx/arch')
-rw-r--r-- | nuttx/arch/arm/src/tiva/tiva_timer.c | 22 | ||||
-rw-r--r-- | nuttx/arch/arm/src/tiva/tiva_timer.h | 3 | ||||
-rw-r--r-- | nuttx/arch/arm/src/tiva/tm4c129_syscontrol.c | 13 |
3 files changed, 32 insertions, 6 deletions
diff --git a/nuttx/arch/arm/src/tiva/tiva_timer.c b/nuttx/arch/arm/src/tiva/tiva_timer.c index 42f6027a5..d7cfe0841 100644 --- a/nuttx/arch/arm/src/tiva/tiva_timer.c +++ b/nuttx/arch/arm/src/tiva/tiva_timer.c @@ -47,7 +47,9 @@ #include <nuttx/arch.h> #include <nuttx/irq.h> + #include <arch/irq.h> +#include <arch/board/board.h> #include "up_arch.h" #include "chip/tiva_syscontrol.h" @@ -86,6 +88,7 @@ struct tiva_gptmstate_s /* Variable state values */ + uint32_t frequency; /* Frequency of the input clock */ uint32_t imr; /* Interrupt mask value. Zero if no interrupts */ #ifdef CONFIG_TIVA_TIMER_REGDEBUG @@ -1436,7 +1439,7 @@ TIMER_HANDLE tiva_gptm_configure(const struct tiva_gptmconfig_s *config) while (!tiva_emac_periphrdy()); up_udelay(250); - /* Select the alternal timer clock source is so reuested. The general + /* Select the alternate timer clock source is so requested. The general * purpose timer has the capability of being clocked by either the system * clock or an alternate clock source. By setting the ALTCLK bit in the * GPTM Clock Configuration (GPTMCC) register, software can selects an @@ -1446,10 +1449,11 @@ TIMER_HANDLE tiva_gptm_configure(const struct tiva_gptmconfig_s *config) * * NOTE: The actual alternate clock source selection is a global property * and cannot be configure on a timer-by-timer basis here. That selection - * must be done by common logic early in the initialization sequence. + * must be done by common logic earlier in the initialization sequence. * - * In any case, the caller must provide us with the correct source - * frequency in gptm->frequency field. + * NOTE: Both the frequency of the SysClk (SYSCLK_FREQUENCY) and of the + * alternate clock (ALTCLK_FREQUENCY) must be provided in the board.h + * header file. */ if (config->alternate) @@ -1459,6 +1463,16 @@ TIMER_HANDLE tiva_gptm_configure(const struct tiva_gptmconfig_s *config) regval = tiva_getreg(priv, TIVA_TIMER_CC_OFFSET); regval |= TIMER_CC_ALTCLK; tiva_putreg(priv, TIVA_TIMER_CC_OFFSET, regval); + + /* Remember the frequency of the input clock */ + + priv->frequency = ALTCLK_FREQUENCY; + } + else + { + /* Remember the frequency of the input clock */ + + priv->frequency = SYSCLK_FREQUENCY; } /* Then [re-]configure the timer into the new configuration */ diff --git a/nuttx/arch/arm/src/tiva/tiva_timer.h b/nuttx/arch/arm/src/tiva/tiva_timer.h index 45f4350d5..902790576 100644 --- a/nuttx/arch/arm/src/tiva/tiva_timer.h +++ b/nuttx/arch/arm/src/tiva/tiva_timer.h @@ -212,8 +212,7 @@ struct tiva_gptmconfig_s { uint8_t gptm; /* GPTM number */ uint8_t mode; /* See enum tiva_timer32mode_e */ - uint8_t alternate; /* False: Use SysClk; True: Use alternate clock source */ - uint32_t frequency; /* Frequency of the selected clock source */ + bool alternate; /* False: Use SysClk; True: Use alternate clock source */ }; /* This structure is cast compatible with struct tiva_gptmconfig_s and diff --git a/nuttx/arch/arm/src/tiva/tm4c129_syscontrol.c b/nuttx/arch/arm/src/tiva/tm4c129_syscontrol.c index 626163080..56b8bba9e 100644 --- a/nuttx/arch/arm/src/tiva/tm4c129_syscontrol.c +++ b/nuttx/arch/arm/src/tiva/tm4c129_syscontrol.c @@ -397,4 +397,17 @@ void up_clockconfig(void) pllfreq0 = M2PLLFREQ0(BOARD_PLL_MINT, BOARD_PLL_MFRAC); pllfreq1 = QN2PLLFREQ1(BOARD_PLL_Q, BOARD_PLL_N); tiva_clockconfig(pllfreq0, pllfreq1, BOARD_PLL_SYSDIV); + + /* Set up the alternate clock source + * + * The ALTCLK provides a clock source of numerous frequencies to the + * general-purpose timer, SSI, and UART modules. The default source for + * the ALTCLK is the Precision Internal Oscillator (PIOSC). The + * Hibernation Real-time Clock (RTCOSC) and Low Frequency Internal + * Oscillator (LFIOSC) are alternatives. If the RTCOSC Output is + * selected, the clock source must also be enabled in the Hibernation + * module. + */ + + putreg32(BOARD_ALTCLKCFG, TIVA_SYSCON_ALTCLKCFG); } |