/* SPDX-License-Identifier: GPL-2.0+ */ /* * Copyright (c) 1996, 2003 VIA Networking Technologies, Inc. * All rights reserved. * * Purpose: MAC routines * * Author: Tevin Chen * * Date: May 21, 1996 * * Revision History: * 07-01-2003 Bryan YC Fan: Re-write codes to support VT3253 spec. * 08-25-2003 Kyle Hsu: Porting MAC functions from sim53. * 09-03-2003 Bryan YC Fan: Add vt6655_mac_dis_protect_md & vt6655_mac_en_protect_md */ #ifndef __MAC_H__ #define __MAC_H__ #include "device.h" /*--------------------- Export Definitions -------------------------*/ /* Registers in the MAC */ #define MAC_MAX_CONTEXT_SIZE_PAGE0 256 #define MAC_MAX_CONTEXT_SIZE_PAGE1 128 /* Registers not related to 802.11b */ #define MAC_REG_BCFG0 0x00 #define MAC_REG_BCFG1 0x01 #define MAC_REG_FCR0 0x02 #define MAC_REG_FCR1 0x03 #define MAC_REG_BISTCMD 0x04 #define MAC_REG_BISTSR0 0x05 #define MAC_REG_BISTSR1 0x06 #define MAC_REG_BISTSR2 0x07 #define MAC_REG_I2MCSR 0x08 #define MAC_REG_I2MTGID 0x09 #define MAC_REG_I2MTGAD 0x0A #define MAC_REG_I2MCFG 0x0B #define MAC_REG_I2MDIPT 0x0C #define MAC_REG_I2MDOPT 0x0E #define MAC_REG_PMC0 0x10 #define MAC_REG_PMC1 0x11 #define MAC_REG_STICKHW 0x12 #define MAC_REG_LOCALID 0x14 #define MAC_REG_TESTCFG 0x15 #define MAC_REG_JUMPER0 0x16 #define MAC_REG_JUMPER1 0x17 #define MAC_REG_TMCTL0 0x18 #define MAC_REG_TMCTL1 0x19 #define MAC_REG_TMDATA0 0x1C /* MAC Parameter related */ #define MAC_REG_LRT 0x20 #define MAC_REG_SRT 0x21 #define MAC_REG_SIFS 0x22 #define MAC_REG_DIFS 0x23 #define MAC_REG_EIFS 0x24 #define MAC_REG_SLOT 0x25 #define MAC_REG_BI 0x26 #define MAC_REG_CWMAXMIN0 0x28 #define MAC_REG_LINKOFFTOTM 0x2A #define MAC_REG_SWTMOT 0x2B #define MAC_REG_MIBCNTR 0x2C #define MAC_REG_RTSOKCNT 0x2C #define MAC_REG_RTSFAILCNT 0x2D #define MAC_REG_ACKFAILCNT 0x2E #define MAC_REG_FCSERRCNT 0x2F /* TSF Related */ #define MAC_REG_TSFCNTR 0x30 #define MAC_REG_NEXTTBTT 0x38 #define MAC_REG_TSFOFST 0x40 #define MAC_REG_TFTCTL 0x48 /* WMAC Control/Status Related */ #define MAC_REG_ENCFG 0x4C #define MAC_REG_PAGE1SEL 0x4F #define MAC_REG_CFG 0x50 #define MAC_REG_TEST 0x52 #define MAC_REG_HOSTCR 0x54 #define MAC_REG_MACCR 0x55 #define MAC_REG_RCR 0x56 #define MAC_REG_TCR 0x57 #define MAC_REG_IMR 0x58 #define MAC_REG_ISR 0x5C /* Power Saving Related */ #define MAC_REG_PSCFG 0x60 #define MAC_REG_PSCTL 0x61 #define MAC_REG_PSPWRSIG 0x62 #define MAC_REG_BBCR13 0x63 #define MAC_REG_AIDATIM 0x64 #define MAC_REG_PWBT 0x66 #define MAC_REG_WAKEOKTMR 0x68 #define MAC_REG_CALTMR 0x69 #define MAC_REG_SYNSPACCNT 0x6A #define MAC_REG_WAKSYNOPT 0x6B /* Baseband/IF Control Group */ #define MAC_REG_BBREGCTL 0x6C #define MAC_REG_CHANNEL 0x6D #define MAC_REG_BBREGADR 0x6E #define MAC_REG_BBREGDATA 0x6F #define MAC_REG_IFREGCTL 0x70 #define MAC_REG_IFDATA 0x71 #define MAC_REG_ITRTMSET 0x74 #define MAC_REG_PAPEDELAY 0x77 #define MAC_REG_SOFTPWRCTL 0x78 #define MAC_REG_GPIOCTL0 0x7A #define MAC_REG_GPIOCTL1 0x7B /* MAC DMA Related Group */ #define MAC_REG_TXDMACTL0 0x7C #define MAC_REG_TXDMAPTR0 0x80 #define MAC_REG_AC0DMACTL 0x84 #define MAC_REG_AC0DMAPTR 0x88 #define MAC_REG_BCNDMACTL 0x8C #define MAC_REG_BCNDMAPTR 0x90 #define MAC_REG_RXDMACTL0 0x94 #define MAC_REG_RXDMAPTR0 0x98 #define MAC_REG_RXDMACTL1 0x9C #define MAC_REG_RXDMAPTR1 0xA0 #define MAC_REG_SYNCDMACTL 0xA4 #define MAC_REG_SYNCDMAPTR 0xA8 #define MAC_REG_ATIMDMACTL 0xAC #define MAC_REG_ATIMDMAPTR 0xB0 /* MiscFF PIO related */ #define MAC_REG_MISCFFNDEX 0xB4 #define MAC_REG_MISCFFCTL 0xB6 #define MAC_REG_MISCFFDATA 0xB8 /* Extend SW Timer */ #define MAC_REG_TMDATA1 0xBC /* WOW Related Group */ #define MAC_REG_WAKEUPEN0 0xC0 #define MAC_REG_WAKEUPEN1 0xC1 #define MAC_REG_WAKEUPSR0 0xC2 #define MAC_REG_WAKEUPSR1 0xC3 #define MAC_REG_WAKE128_0 0xC4 #define MAC_REG_WAKE128_1 0xD4 #define MAC_REG_WAKE128_2 0xE4 #define MAC_REG_WAKE128_3 0xF4 /************** Page 1 ******************/ #define MAC_REG_CRC_128_0 0x04 #define MAC_REG_CRC_128_1 0x06 #define MAC_REG_CRC_128_2 0x08 #define MAC_REG_CRC_128_3 0x0A /* MAC Configuration Group */ #define MAC_REG_PAR0 0x0C #define MAC_REG_PAR4 0x10 #define MAC_REG_BSSID0 0x14 #define MAC_REG_BSSID4 0x18 #define MAC_REG_MAR0 0x1C #define MAC_REG_MAR4 0x20 /* MAC RSPPKT INFO Group */ #define MAC_REG_RSPINF_B_1 0x24 #define MAC_REG_RSPINF_B_2 0x28 #define MAC_REG_RSPINF_B_5 0x2C #define MAC_REG_RSPINF_B_11 0x30 #define MAC_REG_RSPINF_A_6 0x34 #define MAC_REG_RSPINF_A_9 0x36 #define MAC_REG_RSPINF_A_12 0x38 #define MAC_REG_RSPINF_A_18 0x3A #define MAC_REG_RSPINF_A_24 0x3C #define MAC_REG_RSPINF_A_36 0x3E #define MAC_REG_RSPINF_A_48 0x40 #define MAC_REG_RSPINF_A_54 0x42 #define MAC_REG_RSPINF_A_72 0x44 /* 802.11h relative */ #define MAC_REG_QUIETINIT 0x60 #define MAC_REG_QUIETGAP 0x62 #define MAC_REG_QUIETDUR 0x64 #define MAC_REG_MSRCTL 0x66 #define MAC_REG_MSRBBSTS 0x67 #define MAC_REG_MSRSTART 0x68 #define MAC_REG_MSRDURATION 0x70 #define MAC_REG_CCAFRACTION 0x72 #define MAC_REG_PWRCCK 0x73 #define MAC_REG_PWROFDM 0x7C /* Bits in the BCFG0 register */ #define BCFG0_PERROFF 0x40 #define BCFG0_MRDMDIS 0x20 #define BCFG0_MRDLDIS 0x10 #define BCFG0_MWMEN 0x08 #define BCFG0_VSERREN 0x02 #define BCFG0_LATMEN 0x01 /* Bits in the BCFG1 register */ #define BCFG1_CFUNOPT 0x80 #define BCFG1_CREQOPT 0x40 #define BCFG1_DMA8 0x10 #define BCFG1_ARBITOPT 0x08 #define BCFG1_PCIMEN 0x04 #define BCFG1_MIOEN 0x02 #define BCFG1_CISDLYEN 0x01 /* Bits in RAMBIST registers */ #define BISTCMD_TSTPAT5 0x00 #define BISTCMD_TSTPATA 0x80 #define BISTCMD_TSTERR 0x20 #define BISTCMD_TSTPATF 0x18 #define BISTCMD_TSTPAT0 0x10 #define BISTCMD_TSTMODE 0x04 #define BISTCMD_TSTITTX 0x03 #define BISTCMD_TSTATRX 0x02 #define BISTCMD_TSTATTX 0x01 #define BISTCMD_TSTRX 0x00 #define BISTSR0_BISTGO 0x01 #define BISTSR1_TSTSR 0x01 #define BISTSR2_CMDPRTEN 0x02 #define BISTSR2_RAMTSTEN 0x01 /* Bits in the I2MCFG EEPROM register */ #define I2MCFG_BOUNDCTL 0x80 #define I2MCFG_WAITCTL 0x20 #define I2MCFG_SCLOECTL 0x10 #define I2MCFG_WBUSYCTL 0x08 #define I2MCFG_NORETRY 0x04 #define I2MCFG_I2MLDSEQ 0x02 #define I2MCFG_I2CMFAST 0x01 /* Bits in the I2MCSR EEPROM register */ #define I2MCSR_EEMW 0x80 #define I2MCSR_EEMR 0x40 #define I2MCSR_AUTOLD 0x08 #define I2MCSR_NACK 0x02 #define I2MCSR_DONE 0x01 /* Bits in the PMC1 register */ #define SPS_RST 0x80 #define PCISTIKY 0x40 #define PME_OVR 0x02 /* Bits in the STICKYHW register */ #define STICKHW_DS1_SHADOW 0x02 #define STICKHW_DS0_SHADOW 0x01 /* Bits in the TMCTL register */ #define TMCTL_TSUSP 0x04 #define TMCTL_TMD 0x02 #define TMCTL_TE 0x01 /* Bits in the TFTCTL register */ #define TFTCTL_HWUTSF 0x80 #define TFTCTL_TBTTSYNC 0x40 #define TFTCTL_HWUTSFEN 0x20 #define TFTCTL_TSFCNTRRD 0x10 #define TFTCTL_TBTTSYNCEN 0x08 #define TFTCTL_TSFSYNCEN 0x04 #define TFTCTL_TSFCNTRST 0x02 #define TFTCTL_TSFCNTREN 0x01 /* Bits in the EnhanceCFG register */ #define ENCFG_BARKERPREAM 0x00020000 #define ENCFG_NXTBTTCFPSTR 0x00010000 #define ENCFG_BCNSUSCLR 0x00000200 #define ENCFG_BCNSUSIND 0x00000100 #define ENCFG_CFP_PROTECTEN 0x00000040 #define ENCFG_PROTECTMD 0x00000020 #define ENCFG_HWPARCFP 0x00000010 #define ENCFG_CFNULRSP 0x00000004 #define ENCFG_BBTYPE_MASK 0x00000003 #define ENCFG_BBTYPE_G 0x00000002 #define ENCFG_BBTYPE_B 0x00000001 #define ENCFG_BBTYPE_A 0x00000000 /* Bits in the Page1Sel register */ #define PAGE1_SEL 0x01 /* Bits in the CFG register */ #define CFG_TKIPOPT 0x80 #define CFG_RXDMAOPT 0x40 #define CFG_TMOT_SW 0x20 #define CFG_TMOT_HWLONG 0x10 #define CFG_TMOT_HW 0x00 #define CFG_CFPENDOPT 0x08 #define CFG_BCNSUSEN 0x04 #define CFG_NOTXTIMEOUT 0x02 #define CFG_NOBUFOPT 0x01 /* Bits in the TEST register */ #define TEST_LBEXT 0x80 #define TEST_LBINT 0x40 #define TEST_LBNONE 0x00 #define TEST_SOFTINT 0x20 #define TEST_CONTTX 0x10 #define TEST_TXPE 0x08 #define TEST_NAVDIS 0x04 #define TEST_NOCTS 0x02 #define TEST_NOACK 0x01 /* Bits in the HOSTCR register */ #define HOSTCR_TXONST 0x80 #define HOSTCR_RXONST 0x40 #define HOSTCR_ADHOC 0x20 /* Network Type 1 = Ad-hoc */ #define HOSTCR_AP 0x10 /* Port Type 1 = AP */ #define HOSTCR_TXON 0x08 /* 0000 1000 */ #define HOSTCR_RXON 0x04 /* 0000 0100 */ #define HOSTCR_MACEN 0x02 /* 0000 0010 */ #define HOSTCR_SOFTRST 0x01 /* 0000 0001 */ /* Bits in the MACCR register */ #define MACCR_SYNCFLUSHOK 0x04 #define MACCR_SYNCFLUSH 0x02 #define MACCR_CLRNAV 0x01 /* Bits in the MAC_REG_GPIOCTL0 register */ #define LED_ACTSET 0x01 #define LED_RFOFF 0x02 #define LED_NOCONNECT 0x04 /* Bits in the RCR register */ #define RCR_SSID 0x80 #define RCR_RXALLTYPE 0x40 #define RCR_UNICAST 0x20 #define RCR_BROADCAST 0x10 #define RCR_MULTICAST 0x08 #define RCR_WPAERR 0x04 #define RCR_ERRCRC 0x02 #define RCR_BSSID 0x01 /* Bits in the TCR register */ #define TCR_SYNCDCFOPT 0x02 #define TCR_AUTOBCNTX 0x01 /* Beacon automatically transmit enable */ /* Bits in the IMR register */ #define IMR_MEASURESTART 0x80000000 #define IMR_QUIETSTART 0x20000000 #define IMR_RADARDETECT 0x10000000 #define IMR_MEASUREEND 0x08000000 #define IMR_SOFTTIMER1 0x00200000 #define IMR_RXDMA1 0x00001000 /* 0000 0000 0001 0000 0000 0000 */ #define IMR_RXNOBUF 0x00000800 #define IMR_MIBNEARFULL 0x00000400 #define IMR_SOFTINT 0x00000200 #define IMR_FETALERR 0x00000100 #define IMR_WATCHDOG 0x00000080 #define IMR_SOFTTIMER 0x00000040 #define IMR_GPIO 0x00000020 #define IMR_TBTT 0x00000010 #define IMR_RXDMA0 0x00000008 #define IMR_BNTX 0x00000004 #define IMR_AC0DMA 0x00000002 #define IMR_TXDMA0 0x00000001 /* Bits in the ISR register */ #define ISR_MEASURESTART 0x80000000 #define ISR_QUIETSTART 0x20000000 #define ISR_RADARDETECT 0x10000000 #define ISR_MEASUREEND 0x08000000 #define ISR_SOFTTIMER1 0x00200000 #define ISR_RXDMA1 0x00001000 /* 0000 0000 0001 0000 0000 0000 */ #define ISR_RXNOBUF 0x00000800 /* 0000 0000 0000 1000 0000 0000 */ #define ISR_MIBNEARFULL 0x00000400 /* 0000 0000 0000 0100 0000 0000 */ #define ISR_SOFTINT 0x00000200 #define ISR_FETALERR 0x00000100 #define ISR_WATCHDOG 0x00000080 #define ISR_SOFTTIMER 0x00000040 #define ISR_GPIO 0x00000020 #define ISR_TBTT 0x00000010 #define ISR_RXDMA0 0x00000008 #define ISR_BNTX 0x00000004 #define ISR_AC0DMA 0x00000002 #define ISR_TXDMA0 0x00000001 /* Bits in the PSCFG register */ #define PSCFG_PHILIPMD 0x40 #define PSCFG_WAKECALEN 0x20 #define PSCFG_WAKETMREN 0x10 #define PSCFG_BBPSPROG 0x08 #define PSCFG_WAKESYN 0x04 #define PSCFG_SLEEPSYN 0x02 #define PSCFG_AUTOSLEEP 0x01 /* Bits in the PSCTL register */ #define PSCTL_WAKEDONE 0x20 #define PSCTL_PS 0x10 #define PSCTL_GO2DOZE 0x08 #define PSCTL_LNBCN 0x04 #define PSCTL_ALBCN 0x02 #define PSCTL_PSEN 0x01 /* Bits in the PSPWSIG register */ #define PSSIG_WPE3 0x80 #define PSSIG_WPE2 0x40 #define PSSIG_WPE1 0x20 #define PSSIG_WRADIOPE 0x10 #define PSSIG_SPE3 0x08 #define PSSIG_SPE2 0x04 #define PSSIG_SPE1 0x02 #define PSSIG_SRADIOPE 0x01 /* Bits in the BBREGCTL register */ #define BBREGCTL_DONE 0x04 #define BBREGCTL_REGR 0x02 #define BBREGCTL_REGW 0x01 /* Bits in the IFREGCTL register */ #define IFREGCTL_DONE 0x04 #define IFREGCTL_IFRF 0x02 #define IFREGCTL_REGW 0x01 /* Bits in the SOFTPWRCTL register */ #define SOFTPWRCTL_RFLEOPT 0x0800 #define SOFTPWRCTL_TXPEINV 0x0200 #define SOFTPWRCTL_SWPECTI 0x0100 #define SOFTPWRCTL_SWPAPE 0x0020 #define SOFTPWRCTL_SWCALEN 0x0010 #define SOFTPWRCTL_SWRADIO_PE 0x0008 #define SOFTPWRCTL_SWPE2 0x0004 #define SOFTPWRCTL_SWPE1 0x0002 #define SOFTPWRCTL_SWPE3 0x0001 /* Bits in the GPIOCTL1 register */ #define GPIO1_DATA1 0x20 #define GPIO1_MD1 0x10 #define GPIO1_DATA0 0x02 #define GPIO1_MD0 0x01 /* Bits in the DMACTL register */ #define DMACTL_CLRRUN 0x00080000 #define DMACTL_RUN 0x00000008 #define DMACTL_WAKE 0x00000004 #define DMACTL_DEAD 0x00000002 #define DMACTL_ACTIVE 0x00000001 /* Bits in the RXDMACTL0 register */ #define RX_PERPKT 0x00000100 #define RX_PERPKTCLR 0x01000000 /* Bits in the BCNDMACTL register */ #define BEACON_READY 0x01 /* Bits in the MISCFFCTL register */ #define MISCFFCTL_WRITE 0x0001 /* Bits in WAKEUPEN0 */ #define WAKEUPEN0_DIRPKT 0x10 #define WAKEUPEN0_LINKOFF 0x08 #define WAKEUPEN0_ATIMEN 0x04 #define WAKEUPEN0_TIMEN 0x02 #define WAKEUPEN0_MAGICEN 0x01 /* Bits in WAKEUPEN1 */ #define WAKEUPEN1_128_3 0x08 #define WAKEUPEN1_128_2 0x04 #define WAKEUPEN1_128_1 0x02 #define WAKEUPEN1_128_0 0x01 /* Bits in WAKEUPSR0 */ #define WAKEUPSR0_DIRPKT 0x10 #define WAKEUPSR0_LINKOFF 0x08 #define WAKEUPSR0_ATIMEN 0x04 #define WAKEUPSR0_TIMEN 0x02 #define WAKEUPSR0_MAGICEN 0x01 /* Bits in WAKEUPSR1 */ #define WAKEUPSR1_128_3 0x08 #define WAKEUPSR1_128_2 0x04 #define WAKEUPSR1_128_1 0x02 #define WAKEUPSR1_128_0 0x01 /* Bits in the MAC_REG_GPIOCTL register */ #define GPIO0_MD 0x01 #define GPIO0_DATA 0x02 #define GPIO0_INTMD 0x04 #define GPIO1_MD 0x10 #define GPIO1_DATA 0x20 /* Bits in the MSRCTL register */ #define MSRCTL_FINISH 0x80 #define MSRCTL_READY 0x40 #define MSRCTL_RADARDETECT 0x20 #define MSRCTL_EN 0x10 #define MSRCTL_QUIETTXCHK 0x08 #define MSRCTL_QUIETRPT 0x04 #define MSRCTL_QUIETINT 0x02 #define MSRCTL_QUIETEN 0x01 /* Bits in the MSRCTL1 register */ #define MSRCTL1_TXPWR 0x08 #define MSRCTL1_CSAPAREN 0x04 #define MSRCTL1_TXPAUSE 0x01 /* Loopback mode */ #define MAC_LB_EXT 0x02 #define MAC_LB_INTERNAL 0x01 #define MAC_LB_NONE 0x00 #define DEFAULT_BI 0x200 /* MiscFIFO Offset */ #define MISCFIFO_KEYETRY0 32 #define MISCFIFO_KEYENTRYSIZE 22 #define MISCFIFO_SYNINFO_IDX 10 #define MISCFIFO_SYNDATA_IDX 11 #define MISCFIFO_SYNDATASIZE 21 /* enabled mask value of irq */ #define IMR_MASK_VALUE (IMR_SOFTTIMER1 | \ IMR_RXDMA1 | \ IMR_RXNOBUF | \ IMR_MIBNEARFULL | \ IMR_SOFTINT | \ IMR_FETALERR | \ IMR_WATCHDOG | \ IMR_SOFTTIMER | \ IMR_GPIO | \ IMR_TBTT | \ IMR_RXDMA0 | \ IMR_BNTX | \ IMR_AC0DMA | \ IMR_TXDMA0) /* max time out delay time */ #define W_MAX_TIMEOUT 0xFFF0U /* wait time within loop */ #define CB_DELAY_LOOP_WAIT 10 /* 10ms */ /* revision id */ #define REV_ID_VT3253_A0 0x00 #define REV_ID_VT3253_A1 0x01 #define REV_ID_VT3253_B0 0x08 #define REV_ID_VT3253_B1 0x09 /*--------------------- Export Types ------------------------------*/ /*--------------------- Export Macros ------------------------------*/ #define VT6655_MAC_SELECT_PAGE0(iobase) iowrite8(0, iobase + MAC_REG_PAGE1SEL) #define VT6655_MAC_SELECT_PAGE1(iobase) iowrite8(1, iobase + MAC_REG_PAGE1SEL) #define MAKEWORD(lb, hb) \ ((unsigned short)(((unsigned char)(lb)) | (((unsigned short)((unsigned char)(hb))) << 8))) void vt6655_mac_reg_bits_on(void __iomem *iobase, const u8 reg_offset, const u8 bit_mask); void vt6655_mac_word_reg_bits_on(void __iomem *iobase, const u8 reg_offset, const u16 bit_mask); void vt6655_mac_reg_bits_off(void __iomem *iobase, const u8 reg_offset, const u8 bit_mask); void vt6655_mac_word_reg_bits_off(void __iomem *iobase, const u8 reg_offset, const u16 bit_mask); void vt6655_mac_set_short_retry_limit(struct vnt_private *priv, unsigned char retry_limit); void MACvSetLongRetryLimit(struct vnt_private *priv, unsigned char byRetryLimit); bool MACbSoftwareReset(struct vnt_private *priv); bool MACbShutdown(struct vnt_private *priv); void MACvInitialize(struct vnt_private *priv); void vt6655_mac_set_curr_rx_0_desc_addr(struct vnt_private *priv, u32 curr_desc_addr); void vt6655_mac_set_curr_rx_1_desc_addr(struct vnt_private *priv, u32 curr_desc_addr); void vt6655_mac_set_curr_tx_desc_addr(int tx_type, struct vnt_private *priv, u32 curr_desc_addr); void MACvSetCurrSyncDescAddrEx(struct vnt_private *priv, u32 curr_desc_addr); void MACvSetCurrATIMDescAddrEx(struct vnt_private *priv, u32 curr_desc_addr); void MACvTimer0MicroSDelay(struct vnt_private *priv, unsigned int uDelay); void MACvOneShotTimer1MicroSec(struct vnt_private *priv, unsigned int uDelayTime); void MACvSetMISCFifo(struct vnt_private *priv, unsigned short wOffset, u32 dwData); bool MACbPSWakeup(struct vnt_private *priv); void MACvSetKeyEntry(struct vnt_private *priv, unsigned short wKeyCtl, unsigned int uEntryIdx, unsigned int uKeyIdx, unsigned char *pbyAddr, u32 *pdwKey, unsigned char local_id); void MACvDisableKeyEntry(struct vnt_private *priv, unsigned int uEntryIdx); #endif /* __MAC_H__ */