Return-path: Received: from mtaout01-winn.ispmail.ntl.com ([81.103.221.47]:47612 "EHLO mtaout01-winn.ispmail.ntl.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758877AbXHFAYa (ORCPT ); Sun, 5 Aug 2007 20:24:30 -0400 From: Daniel Drake To: linville@tuxdriver.com Cc: linux-wireless@vger.kernel.org Cc: kune@deine-taler.de Subject: [PATCH] zd1211rw: consistent handling of ZD1211 specific rates Message-Id: <20070806002431.C7A287B409F@zog.reactivated.net> Date: Mon, 6 Aug 2007 01:24:31 +0100 (BST) Sender: linux-wireless-owner@vger.kernel.org List-ID: From: Ulrich Kunitz As pointed out by Daniel Drake, the zd1211rw driver used several different rate values and names throughout the driver. He has written a patch to change it and tweaked it after some pretty wild ideas from my side. But the discussion helped me to understand the problem better and I think I have nailed it down with this patch. A zd-rate will consist from now on of a four-bit "pure" rate value and a modulation type flag as used in the ZD1211 control set used for packet transmission. This is consistent with the usage in the zd_rates table. If possible these zd-rates should be used in the code. Signed-off-by: Ulrich Kunitz Signed-off-by: Daniel Drake --- zd_chip.c | 51 ++++++++++++++++------------- zd_ieee80211.h | 43 +++++++++++++++--------- zd_mac.c | 99 +++++++++++++++---------------------------------------- zd_mac.h | 65 +++++++++++++++++++++++++------------ 4 files changed, 126 insertions(+), 132 deletions(-) Index: linux/drivers/net/wireless/zd1211rw/zd_chip.c =================================================================== --- linux.orig/drivers/net/wireless/zd1211rw/zd_chip.c +++ linux/drivers/net/wireless/zd1211rw/zd_chip.c @@ -1009,19 +1009,19 @@ int zd_chip_set_rts_cts_rate_locked(stru u32 value = 0; /* Modulation bit */ - if (ZD_CS_TYPE(rts_rate) == ZD_CS_OFDM) + if (ZD_MODULATION_TYPE(rts_rate) == ZD_OFDM) rts_mod = ZD_RX_OFDM; dev_dbg_f(zd_chip_dev(chip), "rts_rate=%x preamble=%x\n", rts_rate, preamble); - value |= rts_rate << RTSCTS_SH_RTS_RATE; + value |= ZD_PURE_RATE(rts_rate) << RTSCTS_SH_RTS_RATE; value |= rts_mod << RTSCTS_SH_RTS_MOD_TYPE; value |= preamble << RTSCTS_SH_RTS_PMB_TYPE; value |= preamble << RTSCTS_SH_CTS_PMB_TYPE; /* We always send 11M self-CTS messages, like the vendor driver. */ - value |= ZD_CCK_RATE_11M << RTSCTS_SH_CTS_RATE; + value |= ZD_PURE_RATE(ZD_CCK_RATE_11M) << RTSCTS_SH_CTS_RATE; value |= ZD_RX_CCK << RTSCTS_SH_CTS_MOD_TYPE; return zd_iowrite32_locked(chip, value, CR_RTS_CTS_RATE); @@ -1328,7 +1328,7 @@ int zd_chip_set_basic_rates_locked(struc return zd_iowrite32_locked(chip, cr_rates, CR_BASIC_RATE_TBL); } -static int ofdm_qual_db(u8 status_quality, u8 rate, unsigned int size) +static int ofdm_qual_db(u8 status_quality, u8 zd_rate, unsigned int size) { static const u16 constants[] = { 715, 655, 585, 540, 470, 410, 360, 315, @@ -1342,7 +1342,7 @@ static int ofdm_qual_db(u8 status_qualit /* It seems that their quality parameter is somehow per signal * and is now transferred per bit. */ - switch (rate) { + switch (zd_rate) { case ZD_OFDM_RATE_6M: case ZD_OFDM_RATE_12M: case ZD_OFDM_RATE_24M: @@ -1369,7 +1369,7 @@ static int ofdm_qual_db(u8 status_qualit break; } - switch (rate) { + switch (zd_rate) { case ZD_OFDM_RATE_6M: case ZD_OFDM_RATE_9M: i += 3; @@ -1393,11 +1393,11 @@ static int ofdm_qual_db(u8 status_qualit return i; } -static int ofdm_qual_percent(u8 status_quality, u8 rate, unsigned int size) +static int ofdm_qual_percent(u8 status_quality, u8 zd_rate, unsigned int size) { int r; - r = ofdm_qual_db(status_quality, rate, size); + r = ofdm_qual_db(status_quality, zd_rate, size); ZD_ASSERT(r >= 0); if (r < 0) r = 0; @@ -1458,12 +1458,17 @@ static int cck_qual_percent(u8 status_qu return r <= 100 ? r : 100; } +static inline u8 zd_rate_from_ofdm_plcp_header(const void *rx_frame) +{ + return ZD_OFDM | zd_ofdm_plcp_header_rate(rx_frame); +} + u8 zd_rx_qual_percent(const void *rx_frame, unsigned int size, const struct rx_status *status) { return (status->frame_status&ZD_RX_OFDM) ? ofdm_qual_percent(status->signal_quality_ofdm, - zd_ofdm_plcp_header_rate(rx_frame), + zd_rate_from_ofdm_plcp_header(rx_frame), size) : cck_qual_percent(status->signal_quality_cck); } @@ -1479,32 +1484,32 @@ u8 zd_rx_strength_percent(u8 rssi) u16 zd_rx_rate(const void *rx_frame, const struct rx_status *status) { static const u16 ofdm_rates[] = { - [ZD_OFDM_RATE_6M] = 60, - [ZD_OFDM_RATE_9M] = 90, - [ZD_OFDM_RATE_12M] = 120, - [ZD_OFDM_RATE_18M] = 180, - [ZD_OFDM_RATE_24M] = 240, - [ZD_OFDM_RATE_36M] = 360, - [ZD_OFDM_RATE_48M] = 480, - [ZD_OFDM_RATE_54M] = 540, + [ZD_OFDM_PLCP_RATE_6M] = 60, + [ZD_OFDM_PLCP_RATE_9M] = 90, + [ZD_OFDM_PLCP_RATE_12M] = 120, + [ZD_OFDM_PLCP_RATE_18M] = 180, + [ZD_OFDM_PLCP_RATE_24M] = 240, + [ZD_OFDM_PLCP_RATE_36M] = 360, + [ZD_OFDM_PLCP_RATE_48M] = 480, + [ZD_OFDM_PLCP_RATE_54M] = 540, }; u16 rate; if (status->frame_status & ZD_RX_OFDM) { + /* Deals with PLCP OFDM rate (not zd_rates) */ u8 ofdm_rate = zd_ofdm_plcp_header_rate(rx_frame); rate = ofdm_rates[ofdm_rate & 0xf]; } else { - u8 cck_rate = zd_cck_plcp_header_rate(rx_frame); - switch (cck_rate) { - case ZD_CCK_SIGNAL_1M: + switch (zd_cck_plcp_header_signal(rx_frame)) { + case ZD_CCK_PLCP_SIGNAL_1M: rate = 10; break; - case ZD_CCK_SIGNAL_2M: + case ZD_CCK_PLCP_SIGNAL_2M: rate = 20; break; - case ZD_CCK_SIGNAL_5M5: + case ZD_CCK_PLCP_SIGNAL_5M5: rate = 55; break; - case ZD_CCK_SIGNAL_11M: + case ZD_CCK_PLCP_SIGNAL_11M: rate = 110; break; default: Index: linux/drivers/net/wireless/zd1211rw/zd_ieee80211.h =================================================================== --- linux.orig/drivers/net/wireless/zd1211rw/zd_ieee80211.h +++ linux/drivers/net/wireless/zd1211rw/zd_ieee80211.h @@ -43,21 +43,25 @@ struct ofdm_plcp_header { __le16 service; } __attribute__((packed)); -static inline u8 zd_ofdm_plcp_header_rate( - const struct ofdm_plcp_header *header) +static inline u8 zd_ofdm_plcp_header_rate(const struct ofdm_plcp_header *header) { return header->prefix[0] & 0xf; } -/* These are referred to as zd_rates */ -#define ZD_OFDM_RATE_6M 0xb -#define ZD_OFDM_RATE_9M 0xf -#define ZD_OFDM_RATE_12M 0xa -#define ZD_OFDM_RATE_18M 0xe -#define ZD_OFDM_RATE_24M 0x9 -#define ZD_OFDM_RATE_36M 0xd -#define ZD_OFDM_RATE_48M 0x8 -#define ZD_OFDM_RATE_54M 0xc +/* The following defines give the encoding of the 4-bit rate field in the + * OFDM (802.11a/802.11g) PLCP header. Notify that these values are used to + * define the zd-rate values for OFDM. + * + * See the struct zd_ctrlset definition in zd_mac.h. + */ +#define ZD_OFDM_PLCP_RATE_6M 0xb +#define ZD_OFDM_PLCP_RATE_9M 0xf +#define ZD_OFDM_PLCP_RATE_12M 0xa +#define ZD_OFDM_PLCP_RATE_18M 0xe +#define ZD_OFDM_PLCP_RATE_24M 0x9 +#define ZD_OFDM_PLCP_RATE_36M 0xd +#define ZD_OFDM_PLCP_RATE_48M 0x8 +#define ZD_OFDM_PLCP_RATE_54M 0xc struct cck_plcp_header { u8 signal; @@ -66,15 +70,22 @@ struct cck_plcp_header { __le16 crc16; } __attribute__((packed)); -static inline u8 zd_cck_plcp_header_rate(const struct cck_plcp_header *header) +static inline u8 zd_cck_plcp_header_signal(const struct cck_plcp_header *header) { return header->signal; } -#define ZD_CCK_SIGNAL_1M 0x0a -#define ZD_CCK_SIGNAL_2M 0x14 -#define ZD_CCK_SIGNAL_5M5 0x37 -#define ZD_CCK_SIGNAL_11M 0x6e +/* These defines give the encodings of the signal field in the 802.11b PLCP + * header. The signal field gives the bit rate of the following packet. Even + * if technically wrong we use CCK here also for the 1 MBit/s and 2 MBit/s + * rate to stay consistent with Zydas and our use of the term. + * + * Notify that these values are *not* used in the zd-rates. + */ +#define ZD_CCK_PLCP_SIGNAL_1M 0x0a +#define ZD_CCK_PLCP_SIGNAL_2M 0x14 +#define ZD_CCK_PLCP_SIGNAL_5M5 0x37 +#define ZD_CCK_PLCP_SIGNAL_11M 0x6e enum ieee80211_std { IEEE80211B = 0x01, Index: linux/drivers/net/wireless/zd1211rw/zd_mac.c =================================================================== --- linux.orig/drivers/net/wireless/zd1211rw/zd_mac.c +++ linux/drivers/net/wireless/zd1211rw/zd_mac.c @@ -582,28 +582,6 @@ u8 zd_mac_get_channel(struct zd_mac *mac return channel; } -/* If wrong rate is given, we are falling back to the slowest rate: 1MBit/s */ -static u8 zd_rate_typed(u8 zd_rate) -{ - static const u8 typed_rates[16] = { - [ZD_CCK_RATE_1M] = ZD_CS_CCK|ZD_CCK_RATE_1M, - [ZD_CCK_RATE_2M] = ZD_CS_CCK|ZD_CCK_RATE_2M, - [ZD_CCK_RATE_5_5M] = ZD_CS_CCK|ZD_CCK_RATE_5_5M, - [ZD_CCK_RATE_11M] = ZD_CS_CCK|ZD_CCK_RATE_11M, - [ZD_OFDM_RATE_6M] = ZD_CS_OFDM|ZD_OFDM_RATE_6M, - [ZD_OFDM_RATE_9M] = ZD_CS_OFDM|ZD_OFDM_RATE_9M, - [ZD_OFDM_RATE_12M] = ZD_CS_OFDM|ZD_OFDM_RATE_12M, - [ZD_OFDM_RATE_18M] = ZD_CS_OFDM|ZD_OFDM_RATE_18M, - [ZD_OFDM_RATE_24M] = ZD_CS_OFDM|ZD_OFDM_RATE_24M, - [ZD_OFDM_RATE_36M] = ZD_CS_OFDM|ZD_OFDM_RATE_36M, - [ZD_OFDM_RATE_48M] = ZD_CS_OFDM|ZD_OFDM_RATE_48M, - [ZD_OFDM_RATE_54M] = ZD_CS_OFDM|ZD_OFDM_RATE_54M, - }; - - ZD_ASSERT(ZD_CS_RATE_MASK == 0x0f); - return typed_rates[zd_rate & ZD_CS_RATE_MASK]; -} - int zd_mac_set_mode(struct zd_mac *mac, u32 mode) { struct ieee80211_device *ieee; @@ -707,25 +685,30 @@ int zd_mac_get_range(struct zd_mac *mac, static int zd_calc_tx_length_us(u8 *service, u8 zd_rate, u16 tx_length) { + /* ZD_PURE_RATE() must be used to remove the modulation type flag of + * the zd-rate values. */ static const u8 rate_divisor[] = { - [ZD_CCK_RATE_1M] = 1, - [ZD_CCK_RATE_2M] = 2, - [ZD_CCK_RATE_5_5M] = 11, /* bits must be doubled */ - [ZD_CCK_RATE_11M] = 11, - [ZD_OFDM_RATE_6M] = 6, - [ZD_OFDM_RATE_9M] = 9, - [ZD_OFDM_RATE_12M] = 12, - [ZD_OFDM_RATE_18M] = 18, - [ZD_OFDM_RATE_24M] = 24, - [ZD_OFDM_RATE_36M] = 36, - [ZD_OFDM_RATE_48M] = 48, - [ZD_OFDM_RATE_54M] = 54, + [ZD_PURE_RATE(ZD_CCK_RATE_1M)] = 1, + [ZD_PURE_RATE(ZD_CCK_RATE_2M)] = 2, + + /* bits must be doubled */ + [ZD_PURE_RATE(ZD_CCK_RATE_5_5M)] = 11, + + [ZD_PURE_RATE(ZD_CCK_RATE_11M)] = 11, + [ZD_PURE_RATE(ZD_OFDM_RATE_6M)] = 6, + [ZD_PURE_RATE(ZD_OFDM_RATE_9M)] = 9, + [ZD_PURE_RATE(ZD_OFDM_RATE_12M)] = 12, + [ZD_PURE_RATE(ZD_OFDM_RATE_18M)] = 18, + [ZD_PURE_RATE(ZD_OFDM_RATE_24M)] = 24, + [ZD_PURE_RATE(ZD_OFDM_RATE_36M)] = 36, + [ZD_PURE_RATE(ZD_OFDM_RATE_48M)] = 48, + [ZD_PURE_RATE(ZD_OFDM_RATE_54M)] = 54, }; u32 bits = (u32)tx_length * 8; u32 divisor; - divisor = rate_divisor[zd_rate]; + divisor = rate_divisor[ZD_PURE_RATE(zd_rate)]; if (divisor == 0) return -EINVAL; @@ -748,52 +731,24 @@ static int zd_calc_tx_length_us(u8 *serv return bits/divisor; } -enum { - R2M_SHORT_PREAMBLE = 0x01, - R2M_11A = 0x02, -}; - -static u8 zd_rate_to_modulation(u8 zd_rate, int flags) -{ - u8 modulation; - - modulation = zd_rate_typed(zd_rate); - if (flags & R2M_SHORT_PREAMBLE) { - switch (ZD_CS_RATE(modulation)) { - case ZD_CCK_RATE_2M: - case ZD_CCK_RATE_5_5M: - case ZD_CCK_RATE_11M: - modulation |= ZD_CS_CCK_PREA_SHORT; - return modulation; - } - } - if (flags & R2M_11A) { - if (ZD_CS_TYPE(modulation) == ZD_CS_OFDM) - modulation |= ZD_CS_OFDM_MODE_11A; - } - return modulation; -} - static void cs_set_modulation(struct zd_mac *mac, struct zd_ctrlset *cs, struct ieee80211_hdr_4addr *hdr) { struct ieee80211softmac_device *softmac = ieee80211_priv(mac->netdev); u16 ftype = WLAN_FC_GET_TYPE(le16_to_cpu(hdr->frame_ctl)); - u8 rate, zd_rate; + u8 rate; int is_mgt = (ftype == IEEE80211_FTYPE_MGMT) != 0; int is_multicast = is_multicast_ether_addr(hdr->addr1); int short_preamble = ieee80211softmac_short_preamble_ok(softmac, is_multicast, is_mgt); - int flags = 0; - /* FIXME: 802.11a? */ rate = ieee80211softmac_suggest_txrate(softmac, is_multicast, is_mgt); + cs->modulation = rate_to_zd_rate(rate); - if (short_preamble) - flags |= R2M_SHORT_PREAMBLE; - - zd_rate = rate_to_zd_rate(rate); - cs->modulation = zd_rate_to_modulation(zd_rate, flags); + /* Set short preamble bit when appropriate */ + if (short_preamble && ZD_MODULATION_TYPE(cs->modulation) == ZD_CCK + && cs->modulation != ZD_CCK_RATE_1M) + cs->modulation |= ZD_CCK_PREA_SHORT; } static void cs_set_control(struct zd_mac *mac, struct zd_ctrlset *cs, @@ -832,7 +787,7 @@ static void cs_set_control(struct zd_mac cs->control |= ZD_CS_RTS; /* Use CTS-to-self protection if required */ - if (ZD_CS_TYPE(cs->modulation) == ZD_CS_OFDM && + if (ZD_MODULATION_TYPE(cs->modulation) == ZD_OFDM && ieee80211softmac_protection_needed(softmac)) { /* FIXME: avoid sending RTS *and* self-CTS, is that correct? */ cs->control &= ~ZD_CS_RTS; @@ -893,7 +848,7 @@ static int fill_ctrlset(struct zd_mac *m * - see line 53 of zdinlinef.h */ cs->service = 0; - r = zd_calc_tx_length_us(&cs->service, ZD_CS_RATE(cs->modulation), + r = zd_calc_tx_length_us(&cs->service, ZD_RATE(cs->modulation), le16_to_cpu(cs->tx_length)); if (r < 0) return r; @@ -902,7 +857,7 @@ static int fill_ctrlset(struct zd_mac *m if (next_frag_len == 0) { cs->next_frame_length = 0; } else { - r = zd_calc_tx_length_us(NULL, ZD_CS_RATE(cs->modulation), + r = zd_calc_tx_length_us(NULL, ZD_RATE(cs->modulation), next_frag_len); if (r < 0) return r; Index: linux/drivers/net/wireless/zd1211rw/zd_mac.h =================================================================== --- linux.orig/drivers/net/wireless/zd1211rw/zd_mac.h +++ linux/drivers/net/wireless/zd1211rw/zd_mac.h @@ -40,28 +40,51 @@ struct zd_ctrlset { #define ZD_CS_RESERVED_SIZE 25 -/* zd_crtlset field modulation */ -#define ZD_CS_RATE_MASK 0x0f -#define ZD_CS_TYPE_MASK 0x10 -#define ZD_CS_RATE(modulation) ((modulation) & ZD_CS_RATE_MASK) -#define ZD_CS_TYPE(modulation) ((modulation) & ZD_CS_TYPE_MASK) - -#define ZD_CS_CCK 0x00 -#define ZD_CS_OFDM 0x10 - -/* These are referred to as zd_rates */ -#define ZD_CCK_RATE_1M 0x00 -#define ZD_CCK_RATE_2M 0x01 -#define ZD_CCK_RATE_5_5M 0x02 -#define ZD_CCK_RATE_11M 0x03 -/* The rates for OFDM are encoded as in the PLCP header. Use ZD_OFDM_RATE_*. +/* The field modulation of struct zd_ctrlset controls the bit rate, the use + * of short or long preambles in 802.11b (CCK mode) or the use of 802.11a or + * 802.11g in OFDM mode. + * + * The term zd-rate is used for the combination of the modulation type flag + * and the "pure" rate value. */ +#define ZD_PURE_RATE_MASK 0x0f +#define ZD_MODULATION_TYPE_MASK 0x10 +#define ZD_RATE_MASK (ZD_PURE_RATE_MASK|ZD_MODULATION_TYPE_MASK) +#define ZD_PURE_RATE(modulation) ((modulation) & ZD_PURE_RATE_MASK) +#define ZD_MODULATION_TYPE(modulation) ((modulation) & ZD_MODULATION_TYPE_MASK) +#define ZD_RATE(modulation) ((modulation) & ZD_RATE_MASK) + +/* The two possible modulation types. Notify that 802.11b doesn't use the CCK + * codeing for the 1 and 2 MBit/s rate. We stay with the term here to remain + * consistent with uses the term at other places. + */ +#define ZD_CCK 0x00 +#define ZD_OFDM 0x10 + +/* The ZD1211 firmware uses proprietary encodings of the 802.11b (CCK) rates. + * For OFDM the PLCP rate encodings are used. We combine these "pure" rates + * with the modulation type flag and call the resulting values zd-rates. + */ +#define ZD_CCK_RATE_1M (ZD_CCK|0x00) +#define ZD_CCK_RATE_2M (ZD_CCK|0x01) +#define ZD_CCK_RATE_5_5M (ZD_CCK|0x02) +#define ZD_CCK_RATE_11M (ZD_CCK|0x03) +#define ZD_OFDM_RATE_6M (ZD_OFDM|ZD_OFDM_PLCP_RATE_6M) +#define ZD_OFDM_RATE_9M (ZD_OFDM|ZD_OFDM_PLCP_RATE_9M) +#define ZD_OFDM_RATE_12M (ZD_OFDM|ZD_OFDM_PLCP_RATE_12M) +#define ZD_OFDM_RATE_18M (ZD_OFDM|ZD_OFDM_PLCP_RATE_18M) +#define ZD_OFDM_RATE_24M (ZD_OFDM|ZD_OFDM_PLCP_RATE_24M) +#define ZD_OFDM_RATE_36M (ZD_OFDM|ZD_OFDM_PLCP_RATE_36M) +#define ZD_OFDM_RATE_48M (ZD_OFDM|ZD_OFDM_PLCP_RATE_48M) +#define ZD_OFDM_RATE_54M (ZD_OFDM|ZD_OFDM_PLCP_RATE_54M) -/* bit 5 is preamble (when in CCK mode), or a/g selection (when in OFDM mode) */ -#define ZD_CS_CCK_PREA_LONG 0x00 -#define ZD_CS_CCK_PREA_SHORT 0x20 -#define ZD_CS_OFDM_MODE_11G 0x00 -#define ZD_CS_OFDM_MODE_11A 0x20 +/* The bit 5 of the zd_ctrlset modulation field controls the preamble in CCK + * mode or the 802.11a/802.11g selection in OFDM mode. + */ +#define ZD_CCK_PREA_LONG 0x00 +#define ZD_CCK_PREA_SHORT 0x20 +#define ZD_OFDM_MODE_11G 0x00 +#define ZD_OFDM_MODE_11A 0x20 /* zd_ctrlset control field */ #define ZD_CS_NEED_RANDOM_BACKOFF 0x01