From e8b2b7ba1200de8e50788e358e2d945a0c0fcfad Mon Sep 17 00:00:00 2001 From: Rabeeh Khoury Date: Sun, 22 Mar 2009 17:30:32 +0200 Subject: [PATCH] [ARM] Kirkwood: clock gating for unused peripherals To save power: 1. Enabling clock gating of unused peripherals 2. PLL and PHY of the units are also disabled (when possible. Signed-off-by: Rabeeh Khoury Signed-off-by: Nicolas Pitre --- arch/arm/mach-kirkwood/common.c | 59 +++++++++++++++++++ .../mach-kirkwood/include/mach/bridge-regs.h | 18 ++++++ .../arm/mach-kirkwood/include/mach/kirkwood.h | 7 +++ arch/arm/mach-kirkwood/pcie.c | 4 ++ 4 files changed, 88 insertions(+) diff --git a/arch/arm/mach-kirkwood/common.c b/arch/arm/mach-kirkwood/common.c index 6e3eb1a6a660..d127731f47dc 100644 --- a/arch/arm/mach-kirkwood/common.c +++ b/arch/arm/mach-kirkwood/common.c @@ -55,6 +55,13 @@ void __init kirkwood_map_io(void) iotable_init(kirkwood_io_desc, ARRAY_SIZE(kirkwood_io_desc)); } +/* + * Default clock control bits. Any bit _not_ set in this variable + * will be cleared from the hardware after platform devices have been + * registered. Some reserved bits must be set to 1. + */ +unsigned int kirkwood_clk_ctrl = CGC_DUNIT | CGC_RESERVED; + /***************************************************************************** * EHCI @@ -96,6 +103,7 @@ static struct platform_device kirkwood_ehci = { void __init kirkwood_ehci_init(void) { + kirkwood_clk_ctrl |= CGC_USB0; platform_device_register(&kirkwood_ehci); } @@ -152,6 +160,7 @@ static struct platform_device kirkwood_ge00 = { void __init kirkwood_ge00_init(struct mv643xx_eth_platform_data *eth_data) { + kirkwood_clk_ctrl |= CGC_GE0; eth_data->shared = &kirkwood_ge00_shared; kirkwood_ge00.dev.platform_data = eth_data; @@ -213,6 +222,7 @@ static struct platform_device kirkwood_ge01 = { void __init kirkwood_ge01_init(struct mv643xx_eth_platform_data *eth_data) { + kirkwood_clk_ctrl |= CGC_GE1; eth_data->shared = &kirkwood_ge01_shared; kirkwood_ge01.dev.platform_data = eth_data; @@ -287,6 +297,7 @@ static struct platform_device kirkwood_nand_flash = { void __init kirkwood_nand_init(struct mtd_partition *parts, int nr_parts, int chip_delay) { + kirkwood_clk_ctrl |= CGC_RUNIT; kirkwood_nand_data.parts = parts; kirkwood_nand_data.nr_parts = nr_parts; kirkwood_nand_data.chip_delay = chip_delay; @@ -338,6 +349,9 @@ static struct platform_device kirkwood_sata = { void __init kirkwood_sata_init(struct mv_sata_platform_data *sata_data) { + kirkwood_clk_ctrl |= CGC_SATA0; + if (sata_data->n_ports > 1) + kirkwood_clk_ctrl |= CGC_SATA1; sata_data->dram = &kirkwood_mbus_dram_info; kirkwood_sata.dev.platform_data = sata_data; platform_device_register(&kirkwood_sata); @@ -383,6 +397,7 @@ void __init kirkwood_sdio_init(struct mvsdio_platform_data *mvsdio_data) else mvsdio_data->clock = 200000000; mvsdio_data->dram = &kirkwood_mbus_dram_info; + kirkwood_clk_ctrl |= CGC_SDIO; kirkwood_sdio.dev.platform_data = mvsdio_data; platform_device_register(&kirkwood_sdio); } @@ -414,6 +429,7 @@ static struct platform_device kirkwood_spi = { void __init kirkwood_spi_init() { + kirkwood_clk_ctrl |= CGC_RUNIT; platform_device_register(&kirkwood_spi); } @@ -634,6 +650,7 @@ static struct platform_device kirkwood_xor01_channel = { static void __init kirkwood_xor0_init(void) { + kirkwood_clk_ctrl |= CGC_XOR0; platform_device_register(&kirkwood_xor0_shared); /* @@ -732,6 +749,7 @@ static struct platform_device kirkwood_xor11_channel = { static void __init kirkwood_xor1_init(void) { + kirkwood_clk_ctrl |= CGC_XOR1; platform_device_register(&kirkwood_xor1_shared); /* @@ -844,3 +862,44 @@ void __init kirkwood_init(void) kirkwood_xor0_init(); kirkwood_xor1_init(); } + +static int __init kirkwood_clock_gate(void) +{ + unsigned int curr = readl(CLOCK_GATING_CTRL); + + printk(KERN_DEBUG "Gating clock of unused units\n"); + printk(KERN_DEBUG "before: 0x%08x\n", curr); + + /* Make sure those units are accessible */ + writel(curr | CGC_SATA0 | CGC_SATA1 | CGC_PEX0, CLOCK_GATING_CTRL); + + /* For SATA: first shutdown the phy */ + if (!(kirkwood_clk_ctrl & CGC_SATA0)) { + /* Disable PLL and IVREF */ + writel(readl(SATA0_PHY_MODE_2) & ~0xf, SATA0_PHY_MODE_2); + /* Disable PHY */ + writel(readl(SATA0_IF_CTRL) | 0x200, SATA0_IF_CTRL); + } + if (!(kirkwood_clk_ctrl & CGC_SATA1)) { + /* Disable PLL and IVREF */ + writel(readl(SATA1_PHY_MODE_2) & ~0xf, SATA1_PHY_MODE_2); + /* Disable PHY */ + writel(readl(SATA1_IF_CTRL) | 0x200, SATA1_IF_CTRL); + } + + /* For PCIe: first shutdown the phy */ + if (!(kirkwood_clk_ctrl & CGC_PEX0)) { + writel(readl(PCIE_LINK_CTRL) | 0x10, PCIE_LINK_CTRL); + while (1) + if (readl(PCIE_STATUS) & 0x1) + break; + writel(readl(PCIE_LINK_CTRL) & ~0x10, PCIE_LINK_CTRL); + } + + /* Now gate clock the required units */ + writel(kirkwood_clk_ctrl, CLOCK_GATING_CTRL); + printk(KERN_DEBUG " after: 0x%08x\n", readl(CLOCK_GATING_CTRL)); + + return 0; +} +late_initcall(kirkwood_clock_gate); diff --git a/arch/arm/mach-kirkwood/include/mach/bridge-regs.h b/arch/arm/mach-kirkwood/include/mach/bridge-regs.h index 4f7029f521cc..00d96abb718c 100644 --- a/arch/arm/mach-kirkwood/include/mach/bridge-regs.h +++ b/arch/arm/mach-kirkwood/include/mach/bridge-regs.h @@ -39,4 +39,22 @@ #define L2_CONFIG_REG (BRIDGE_VIRT_BASE | 0x0128) #define L2_WRITETHROUGH 0x00000010 +#define CLOCK_GATING_CTRL (BRIDGE_VIRT_BASE | 0x11c) +#define CGC_GE0 (1 << 0) +#define CGC_PEX0 (1 << 2) +#define CGC_USB0 (1 << 3) +#define CGC_SDIO (1 << 4) +#define CGC_TSU (1 << 5) +#define CGC_DUNIT (1 << 6) +#define CGC_RUNIT (1 << 7) +#define CGC_XOR0 (1 << 8) +#define CGC_AUDIO (1 << 9) +#define CGC_SATA0 (1 << 14) +#define CGC_SATA1 (1 << 15) +#define CGC_XOR1 (1 << 16) +#define CGC_CRYPTO (1 << 17) +#define CGC_GE1 (1 << 19) +#define CGC_TDM (1 << 20) +#define CGC_RESERVED ((1 << 18) | (0x6 << 21)) + #endif diff --git a/arch/arm/mach-kirkwood/include/mach/kirkwood.h b/arch/arm/mach-kirkwood/include/mach/kirkwood.h index f20ff6460485..f49a29bf3369 100644 --- a/arch/arm/mach-kirkwood/include/mach/kirkwood.h +++ b/arch/arm/mach-kirkwood/include/mach/kirkwood.h @@ -65,6 +65,8 @@ #define BRIDGE_VIRT_BASE (KIRKWOOD_REGS_VIRT_BASE | 0x20000) #define PCIE_VIRT_BASE (KIRKWOOD_REGS_VIRT_BASE | 0x40000) +#define PCIE_LINK_CTRL (PCIE_VIRT_BASE | 0x70) +#define PCIE_STATUS (PCIE_VIRT_BASE | 0x1a04) #define USB_PHYS_BASE (KIRKWOOD_REGS_PHYS_BASE | 0x50000) @@ -81,6 +83,11 @@ #define GE01_PHYS_BASE (KIRKWOOD_REGS_PHYS_BASE | 0x74000) #define SATA_PHYS_BASE (KIRKWOOD_REGS_PHYS_BASE | 0x80000) +#define SATA_VIRT_BASE (KIRKWOOD_REGS_VIRT_BASE | 0x80000) +#define SATA0_IF_CTRL (SATA_VIRT_BASE | 0x2050) +#define SATA0_PHY_MODE_2 (SATA_VIRT_BASE | 0x2330) +#define SATA1_IF_CTRL (SATA_VIRT_BASE | 0x4050) +#define SATA1_PHY_MODE_2 (SATA_VIRT_BASE | 0x4330) #define SDIO_PHYS_BASE (KIRKWOOD_REGS_PHYS_BASE | 0x90000) diff --git a/arch/arm/mach-kirkwood/pcie.c b/arch/arm/mach-kirkwood/pcie.c index 73fccacd1a73..d90b9aae308d 100644 --- a/arch/arm/mach-kirkwood/pcie.c +++ b/arch/arm/mach-kirkwood/pcie.c @@ -14,6 +14,7 @@ #include #include #include +#include #include "common.h" @@ -95,6 +96,7 @@ static struct pci_ops pcie_ops = { static int kirkwood_pcie_setup(int nr, struct pci_sys_data *sys) { struct resource *res; + extern unsigned int kirkwood_clk_ctrl; /* * Generic PCIe unit setup. @@ -133,6 +135,8 @@ static int kirkwood_pcie_setup(int nr, struct pci_sys_data *sys) sys->resource[2] = NULL; sys->io_offset = 0; + kirkwood_clk_ctrl |= CGC_PEX0; + return 1; } -- 2.20.1