Subject: Re: [PATCH part1 v2 1/9] Add udbg driver using the PS3 gelic Ethernet device

From: Geoff Levand <[email-masked]>
Date: Tue, 23 Aug 2011 13:53:24 -0700

Hi,

We had some questions as to why we have this totally separate driver
from the gelic driver, so I think it worthwhile to have an
explanation of why in the commit log.   Otherwise, the code looks
OK.

-Geoff

> From: Hector Martin <[email-masked]>
> 
> Signed-off-by: Hector Martin <[email-masked]>
> [a.heider: Various cleanups to make checkpatch.pl happy]
> Signed-off-by: Andre Heider <[email-masked]>
> ---
>  arch/powerpc/Kconfig.debug              |    8 +
>  arch/powerpc/include/asm/udbg.h         |    1 +
>  arch/powerpc/kernel/udbg.c              |    2 +
>  arch/powerpc/platforms/ps3/Kconfig      |   12 ++
>  arch/powerpc/platforms/ps3/Makefile     |    1 +
>  arch/powerpc/platforms/ps3/gelic_udbg.c |  273 +++++++++++++++++++++++++++++++
>  drivers/net/ps3_gelic_net.c             |    3 +
>  drivers/net/ps3_gelic_net.h             |    6 +
>  8 files changed, 306 insertions(+), 0 deletions(-)
>  create mode 100644 arch/powerpc/platforms/ps3/gelic_udbg.c
> 
> diff --git a/arch/powerpc/Kconfig.debug b/arch/powerpc/Kconfig.debug
> index 067cb84..ab2335f 100644
> --- a/arch/powerpc/Kconfig.debug
> +++ b/arch/powerpc/Kconfig.debug
> @@ -258,6 +258,14 @@ config PPC_EARLY_DEBUG_WSP
>  	depends on PPC_WSP
>  	select PPC_UDBG_16550
>  
> +config PPC_EARLY_DEBUG_PS3GELIC
> +	bool "Early debugging through the PS3 Ethernet port"
> +	depends on PPC_PS3
> +	select PS3GELIC_UDBG
> +	help
> +	  Select this to enable early debugging for the PlayStation3 via
> +	  UDP broadcasts sent out through the Ethernet port.
> +
>  endchoice
>  
>  config PPC_EARLY_DEBUG_HVSI_VTERMNO
> diff --git a/arch/powerpc/include/asm/udbg.h b/arch/powerpc/include/asm/udbg.h
> index 93e05d1..7cf796f 100644
> --- a/arch/powerpc/include/asm/udbg.h
> +++ b/arch/powerpc/include/asm/udbg.h
> @@ -54,6 +54,7 @@ extern void __init udbg_init_40x_realmode(void);
>  extern void __init udbg_init_cpm(void);
>  extern void __init udbg_init_usbgecko(void);
>  extern void __init udbg_init_wsp(void);
> +extern void __init udbg_init_ps3gelic(void);
>  
>  #endif /* __KERNEL__ */
>  #endif /* _ASM_POWERPC_UDBG_H */
> diff --git a/arch/powerpc/kernel/udbg.c b/arch/powerpc/kernel/udbg.c
> index faa82c1..5b3e98e 100644
> --- a/arch/powerpc/kernel/udbg.c
> +++ b/arch/powerpc/kernel/udbg.c
> @@ -67,6 +67,8 @@ void __init udbg_early_init(void)
>  	udbg_init_usbgecko();
>  #elif defined(CONFIG_PPC_EARLY_DEBUG_WSP)
>  	udbg_init_wsp();
> +#elif defined(CONFIG_PPC_EARLY_DEBUG_PS3GELIC)
> +	udbg_init_ps3gelic();
>  #endif
>  
>  #ifdef CONFIG_PPC_EARLY_DEBUG
> diff --git a/arch/powerpc/platforms/ps3/Kconfig b/arch/powerpc/platforms/ps3/Kconfig
> index dfe316b..476d9d9 100644
> --- a/arch/powerpc/platforms/ps3/Kconfig
> +++ b/arch/powerpc/platforms/ps3/Kconfig
> @@ -148,4 +148,16 @@ config PS3_LPM
>  	  profiling support of the Cell processor with programs like
>  	  oprofile and perfmon2, then say Y or M, otherwise say N.
>  
> +config PS3GELIC_UDBG
> +	bool "PS3 udbg output via UDP broadcasts on Ethernet"
> +	depends on PPC_PS3
> +	help
> +	  Enables udbg early debugging output by sending broadcast UDP
> +	  via the Ethernet port (UDP port number 18194).
> +
> +	  This driver uses a trivial implementation and is independent
> +	  from the main network driver.
> +
> +	  If in doubt, say N here.
> +
>  endmenu
> diff --git a/arch/powerpc/platforms/ps3/Makefile b/arch/powerpc/platforms/ps3/Makefile
> index ac1bdf8..02b9e63 100644
> --- a/arch/powerpc/platforms/ps3/Makefile
> +++ b/arch/powerpc/platforms/ps3/Makefile
> @@ -2,6 +2,7 @@ obj-y += setup.o mm.o time.o hvcall.o htab.o repository.o
>  obj-y += interrupt.o exports.o os-area.o
>  obj-y += system-bus.o
>  
> +obj-$(CONFIG_PS3GELIC_UDBG) += gelic_udbg.o
>  obj-$(CONFIG_SMP) += smp.o
>  obj-$(CONFIG_SPU_BASE) += spu.o
>  obj-y += device-init.o
> diff --git a/arch/powerpc/platforms/ps3/gelic_udbg.c b/arch/powerpc/platforms/ps3/gelic_udbg.c
> new file mode 100644
> index 0000000..20b46a1
> --- /dev/null
> +++ b/arch/powerpc/platforms/ps3/gelic_udbg.c
> @@ -0,0 +1,273 @@
> +/*
> + * udbg debug output routine via GELIC UDP broadcasts
> + *
> + * Copyright (C) 2007 Sony Computer Entertainment Inc.
> + * Copyright 2006, 2007 Sony Corporation
> + * Copyright (C) 2010 Hector Martin <[email-masked]>
> + * Copyright (C) 2011 Andre Heider <[email-masked]>
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * as published by the Free Software Foundation; either version 2
> + * of the License, or (at your option) any later version.
> + *
> + */
> +
> +#include <asm/io.h>
> +#include <asm/udbg.h>
> +#include <asm/lv1call.h>
> +
> +#define GELIC_BUS_ID 1
> +#define GELIC_DEVICE_ID 0
> +#define GELIC_DEBUG_PORT 18194
> +#define GELIC_MAX_MESSAGE_SIZE 1000
> +
> +#define GELIC_LV1_GET_MAC_ADDRESS 1
> +#define GELIC_LV1_GET_VLAN_ID 4
> +#define GELIC_LV1_VLAN_TX_ETHERNET_0 2
> +
> +#define GELIC_DESCR_DMA_STAT_MASK 0xf0000000
> +#define GELIC_DESCR_DMA_CARDOWNED 0xa0000000
> +
> +#define GELIC_DESCR_TX_DMA_IKE 0x00080000
> +#define GELIC_DESCR_TX_DMA_NO_CHKSUM 0x00000000
> +#define GELIC_DESCR_TX_DMA_FRAME_TAIL 0x00040000
> +
> +#define GELIC_DESCR_DMA_CMD_NO_CHKSUM (GELIC_DESCR_DMA_CARDOWNED | \
> +				       GELIC_DESCR_TX_DMA_IKE | \
> +				       GELIC_DESCR_TX_DMA_NO_CHKSUM)
> +
> +static u64 bus_addr;
> +
> +struct gelic_descr {
> +	/* as defined by the hardware */
> +	__be32 buf_addr;
> +	__be32 buf_size;
> +	__be32 next_descr_addr;
> +	__be32 dmac_cmd_status;
> +	__be32 result_size;
> +	__be32 valid_size;	/* all zeroes for tx */
> +	__be32 data_status;
> +	__be32 data_error;	/* all zeroes for tx */
> +} __attribute__((aligned(32)));
> +
> +struct debug_block {
> +	struct gelic_descr descr;
> +	u8 pkt[1520];
> +} __packed;
> +
> +struct ethhdr {
> +	u8 dest[6];
> +	u8 src[6];
> +	u16 type;
> +} __packed;
> +
> +struct vlantag {
> +	u16 vlan;
> +	u16 subtype;
> +} __packed;
> +
> +struct iphdr {
> +	u8 ver_len;
> +	u8 dscp_ecn;
> +	u16 total_length;
> +	u16 ident;
> +	u16 frag_off_flags;
> +	u8 ttl;
> +	u8 proto;
> +	u16 checksum;
> +	u32 src;
> +	u32 dest;
> +} __packed;
> +
> +struct udphdr {
> +	u16 src;
> +	u16 dest;
> +	u16 len;
> +	u16 checksum;
> +} __packed;
> +
> +static __iomem struct ethhdr *h_eth;
> +static __iomem struct vlantag *h_vlan;
> +static __iomem struct iphdr *h_ip;
> +static __iomem struct udphdr *h_udp;
> +
> +static __iomem char *pmsg;
> +static __iomem char *pmsgc;
> +
> +static __iomem struct debug_block dbg __attribute__((aligned(32)));
> +
> +static int header_size;
> +
> +static void map_dma_mem(int bus_id, int dev_id, void *start, size_t len,
> +			u64 *real_bus_addr)
> +{
> +	s64 result;
> +	u64 real_addr = ((u64)start) & 0x0fffffffffffffffUL;
> +	u64 real_end = real_addr + len;
> +	u64 map_start = real_addr & ~0xfff;
> +	u64 map_end = (real_end + 0xfff) & ~0xfff;
> +	u64 bus_addr = 0;
> +
> +	u64 flags = 0xf800000000000000UL;
> +
> +	result = lv1_allocate_device_dma_region(bus_id, dev_id,
> +						map_end - map_start, 12, 0,
> +						&bus_addr);
> +	if (result)
> +		lv1_panic(0);
> +
> +	result = lv1_map_device_dma_region(bus_id, dev_id, map_start,
> +					   bus_addr, map_end - map_start,
> +					   flags);
> +	if (result)
> +		lv1_panic(0);
> +
> +	*real_bus_addr = bus_addr + real_addr - map_start;
> +}
> +
> +static int unmap_dma_mem(int bus_id, int dev_id, u64 bus_addr, size_t len)
> +{
> +	s64 result;
> +	u64 real_bus_addr;
> +
> +	real_bus_addr = bus_addr & ~0xfff;
> +	len += bus_addr - real_bus_addr;
> +	len = (len + 0xfff) & ~0xfff;
> +
> +	result = lv1_unmap_device_dma_region(bus_id, dev_id, real_bus_addr,
> +					     len);
> +	if (result)
> +		return result;
> +
> +	return lv1_free_device_dma_region(bus_id, dev_id, real_bus_addr);
> +}
> +
> +static void gelic_debug_init(void)
> +{
> +	s64 result;
> +	u64 v2;
> +	u64 mac;
> +	u64 vlan_id;
> +
> +	result = lv1_open_device(GELIC_BUS_ID, GELIC_DEVICE_ID, 0);
> +	if (result)
> +		lv1_panic(0);
> +
> +	map_dma_mem(GELIC_BUS_ID, GELIC_DEVICE_ID, &dbg, sizeof(dbg),
> +		    &bus_addr);
> +
> +	memset(&dbg, 0, sizeof(dbg));
> +
> +	dbg.descr.buf_addr = bus_addr + offsetof(struct debug_block, pkt);
> +
> +	wmb();
> +
> +	result = lv1_net_control(GELIC_BUS_ID, GELIC_DEVICE_ID,
> +				 GELIC_LV1_GET_MAC_ADDRESS, 0, 0, 0,
> +				 &mac, &v2);
> +	if (result)
> +		lv1_panic(0);
> +
> +	mac <<= 16;
> +
> +	h_eth = (struct ethhdr *)dbg.pkt;
> +
> +	memset(&h_eth->dest, 0xff, 6);
> +	memcpy(&h_eth->src, &mac, 6);
> +
> +	header_size = sizeof(struct ethhdr);
> +
> +	result = lv1_net_control(GELIC_BUS_ID, GELIC_DEVICE_ID,
> +				 GELIC_LV1_GET_VLAN_ID,
> +				 GELIC_LV1_VLAN_TX_ETHERNET_0, 0, 0,
> +				 &vlan_id, &v2);
> +	if (!result) {
> +		h_eth->type = 0x8100;
> +
> +		header_size += sizeof(struct vlantag);
> +		h_vlan = (struct vlantag *)(h_eth + 1);
> +		h_vlan->vlan = vlan_id;
> +		h_vlan->subtype = 0x0800;
> +		h_ip = (struct iphdr *)(h_vlan + 1);
> +	} else {
> +		h_eth->type = 0x0800;
> +		h_ip = (struct iphdr *)(h_eth + 1);
> +	}
> +
> +	header_size += sizeof(struct iphdr);
> +	h_ip->ver_len = 0x45;
> +	h_ip->ttl = 10;
> +	h_ip->proto = 0x11;
> +	h_ip->src = 0x00000000;
> +	h_ip->dest = 0xffffffff;
> +
> +	header_size += sizeof(struct udphdr);
> +	h_udp = (struct udphdr *)(h_ip + 1);
> +	h_udp->src = GELIC_DEBUG_PORT;
> +	h_udp->dest = GELIC_DEBUG_PORT;
> +
> +	pmsgc = pmsg = (char *)(h_udp + 1);
> +}
> +
> +static void gelic_debug_shutdown(void)
> +{
> +	if (bus_addr)
> +		unmap_dma_mem(GELIC_BUS_ID, GELIC_DEVICE_ID,
> +			      bus_addr, sizeof(dbg));
> +	lv1_close_device(GELIC_BUS_ID, GELIC_DEVICE_ID);
> +}
> +
> +static void gelic_sendbuf(int msgsize)
> +{
> +	u16 *p;
> +	u32 sum;
> +	int i;
> +
> +	dbg.descr.buf_size = header_size + msgsize;
> +	h_ip->total_length = msgsize + sizeof(struct udphdr) +
> +			     sizeof(struct iphdr);
> +	h_udp->len = msgsize + sizeof(struct udphdr);
> +
> +	h_ip->checksum = 0;
> +	sum = 0;
> +	p = (u16 *)h_ip;
> +	for (i = 0; i < 5; i++)
> +		sum += *p++;
> +	h_ip->checksum = ~(sum + (sum >> 16));
> +
> +	dbg.descr.dmac_cmd_status = GELIC_DESCR_DMA_CMD_NO_CHKSUM |
> +				    GELIC_DESCR_TX_DMA_FRAME_TAIL;
> +	dbg.descr.result_size = 0;
> +	dbg.descr.data_status = 0;
> +
> +	wmb();
> +
> +	lv1_net_start_tx_dma(GELIC_BUS_ID, GELIC_DEVICE_ID, bus_addr, 0);
> +
> +	while ((dbg.descr.dmac_cmd_status & GELIC_DESCR_DMA_STAT_MASK) ==
> +	       GELIC_DESCR_DMA_CARDOWNED)
> +		cpu_relax();
> +}
> +
> +static void ps3gelic_udbg_putc(char ch)
> +{
> +	*pmsgc++ = ch;
> +	if (ch == '\n' || (pmsgc-pmsg) >= GELIC_MAX_MESSAGE_SIZE) {
> +		gelic_sendbuf(pmsgc-pmsg);
> +		pmsgc = pmsg;
> +	}
> +}
> +
> +void __init udbg_init_ps3gelic(void)
> +{
> +	gelic_debug_init();
> +	udbg_putc = ps3gelic_udbg_putc;
> +}
> +
> +void udbg_shutdown_ps3gelic(void)
> +{
> +	udbg_putc = NULL;
> +	gelic_debug_shutdown();
> +}
> +EXPORT_SYMBOL(udbg_shutdown_ps3gelic);
> diff --git a/drivers/net/ps3_gelic_net.c b/drivers/net/ps3_gelic_net.c
> index d82a82d..e743c94 100644
> --- a/drivers/net/ps3_gelic_net.c
> +++ b/drivers/net/ps3_gelic_net.c
> @@ -1674,6 +1674,9 @@ static int __devinit ps3_gelic_driver_probe(struct ps3_system_bus_device *dev)
>  	int result;
>  
>  	pr_debug("%s: called\n", __func__);
> +
> +	udbg_shutdown_ps3gelic();
> +
>  	result = ps3_open_hv_device(dev);
>  
>  	if (result) {
> diff --git a/drivers/net/ps3_gelic_net.h b/drivers/net/ps3_gelic_net.h
> index d3fadfb..a93df6a 100644
> --- a/drivers/net/ps3_gelic_net.h
> +++ b/drivers/net/ps3_gelic_net.h
> @@ -359,6 +359,12 @@ static inline void *port_priv(struct gelic_port *port)
>  	return port->priv;
>  }
>  
> +#ifdef CONFIG_PPC_EARLY_DEBUG_PS3GELIC
> +extern void udbg_shutdown_ps3gelic(void);
> +#else
> +static inline void udbg_shutdown_ps3gelic(void) {}
> +#endif
> +
>  extern int gelic_card_set_irq_mask(struct gelic_card *card, u64 mask);
>  /* shared netdev ops */
>  extern void gelic_card_up(struct gelic_card *card);