From fe7cca715c69f66efdc9c64462b0fd0a445331a5 Mon Sep 17 00:00:00 2001 From: Stefan Roese Date: Wed, 19 May 2010 11:13:24 +0200 Subject: ppc4xx: Enable booting with Option E on 460EX/EXr/GT This patch enables booting with option E on the PPC460EX/EXr/GT. When booting with Option E, the PLL is in bypass, CPR0_PLLC[ENG]=0. The Software Boot Configuration Procedure is needed to engage the PLL and perform a chip reset. Signed-off-by: Stefan Roese --- arch/powerpc/cpu/ppc4xx/cpu_init.c | 49 ++++++++++++++++++++++++++++++-------- include/ppc440.h | 7 ++++++ 2 files changed, 46 insertions(+), 10 deletions(-) diff --git a/arch/powerpc/cpu/ppc4xx/cpu_init.c b/arch/powerpc/cpu/ppc4xx/cpu_init.c index 8a6e545..c04eede 100644 --- a/arch/powerpc/cpu/ppc4xx/cpu_init.c +++ b/arch/powerpc/cpu/ppc4xx/cpu_init.c @@ -36,6 +36,26 @@ DECLARE_GLOBAL_DATA_PTR; #define CONFIG_SYS_PLL_RECONFIG 0 #endif +#if defined(CONFIG_440EPX) || \ + defined(CONFIG_460EX) || defined(CONFIG_460GT) +static void reset_with_rli(void) +{ + u32 reg; + + /* + * Set reload inhibit so configuration will persist across + * processor resets + */ + mfcpr(CPR0_ICFG, reg); + reg |= CPR0_ICFG_RLI_MASK; + mtcpr(CPR0_ICFG, reg); + + /* Reset processor if configuration changed */ + __asm__ __volatile__ ("sync; isync"); + mtspr(SPRN_DBCR0, 0x20000000); +} +#endif + void reconfigure_pll(u32 new_cpu_freq) { #if defined(CONFIG_440EPX) @@ -166,19 +186,28 @@ void reconfigure_pll(u32 new_cpu_freq) } } - if (reset_needed) { + /* Now reset the CPU if needed */ + if (reset_needed) + reset_with_rli(); +#endif + +#if defined(CONFIG_460EX) || defined(CONFIG_460GT) + u32 reg; + + /* + * See "9.2.1.1 Booting with Option E" in the 460EX/GT + * users manual + */ + mfcpr(CPR0_PLLC, reg); + if ((reg & (CPR0_PLLC_RST | CPR0_PLLC_ENG)) == CPR0_PLLC_RST) { /* - * Set reload inhibit so configuration will persist across - * processor resets + * Set engage bit */ - mfcpr(CPR0_ICFG, reg); - reg &= ~CPR0_ICFG_RLI_MASK; - reg |= 1 << 31; - mtcpr(CPR0_ICFG, reg); + reg = (reg & ~CPR0_PLLC_RST) | CPR0_PLLC_ENG; + mtcpr(CPR0_PLLC, reg); - /* Reset processor if configuration changed */ - __asm__ __volatile__ ("sync; isync"); - mtspr(SPRN_DBCR0, 0x20000000); + /* Now reset the CPU */ + reset_with_rli(); } #endif } diff --git a/include/ppc440.h b/include/ppc440.h index 5f87d2c..c807dda 100644 --- a/include/ppc440.h +++ b/include/ppc440.h @@ -1719,6 +1719,13 @@ #define CPR0_PERD_PERDV0_MASK 0x07000000 #endif +#if defined(CONFIG_460EX) || defined(CONFIG_460GT) +#define CPR0_ICFG_RLI_MASK 0x80000000 + +#define CPR0_PLLC_RST 0x80000000 +#define CPR0_PLLC_ENG 0x40000000 +#endif + /*----------------------------------------------------------------------------- | PCI Internal Registers et. al. (accessed via plb) +----------------------------------------------------------------------------*/ -- cgit v1.1