[PATCH 1/4] ARM: footbridge: remove addin mode

Arnd Bergmann
2022-08-18T21:23:59Z

From: Arnd Bergmann <arnd@arndb.de>

This does not appear to have been used in many years, we can
kill off some of the uglier code.

Among other things, it avoids a randconfig issue when both modes
are disabled:

arch/arm/mach-footbridge/common.c:149:24: error: 'ebsa285_host_io_desc' defined but not used [-Werror=unused-variable]
149 | static struct map_desc ebsa285_host_io_desc[] __initdata = {
| ^~~~~~~~~~~~~~~~~~~~
arch/arm/mach-footbridge/common.c:136:24: error: 'fb_common_io_desc' defined but not used [-Werror=unused-variable]
136 | static struct map_desc fb_common_io_desc[] __initdata = {
| ^~~~~~~~~~~~~~~~~

The recently added phys_to_dma() functions are now trivial and
could probably be removed again as a follow-up, if anyone knows
how.

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
arch/arm/include/asm/hardware/dec21285.h | 13 ----
arch/arm/mach-footbridge/Kconfig | 28 +------
arch/arm/mach-footbridge/Makefile | 2 +-
arch/arm/mach-footbridge/common.c | 73 ++-----------------
arch/arm/mach-footbridge/dc21285.c | 61 +++++-----------
arch/arm/mach-footbridge/dma.c | 3 +-
.../arm/mach-footbridge/include/mach/memory.h | 22 ------
arch/arm/mach-footbridge/isa.c | 3 -
8 files changed, 30 insertions(+), 175 deletions(-)

diff --git a/arch/arm/include/asm/hardware/dec21285.h b/arch/arm/include/asm/hardware/dec21285.h
index 3f18a56a025d..eee390e8d4dc 100644
--- a/arch/arm/include/asm/hardware/dec21285.h
+++ b/arch/arm/include/asm/hardware/dec21285.h
@@ -81,19 +81,6 @@
#define SA110_CNTL_XCSDIR(x) ((x)<<28)
#define SA110_CNTL_PCICFN (1 << 31)

-/*
- * footbridge_cfn_mode() is used when we want
- * to check whether we are the central function
- */
-#define __footbridge_cfn_mode() (*CSR_SA110_CNTL & SA110_CNTL_PCICFN)
-#if defined(CONFIG_FOOTBRIDGE_HOST) && defined(CONFIG_FOOTBRIDGE_ADDIN)
-#define footbridge_cfn_mode() __footbridge_cfn_mode()
-#elif defined(CONFIG_FOOTBRIDGE_HOST)
-#define footbridge_cfn_mode() (1)
-#else
-#define footbridge_cfn_mode() (0)
-#endif
-
#define CSR_PCIADDR_EXTN DC21285_IO(0x0140)
#define CSR_PREFETCHMEMRANGE DC21285_IO(0x0144)
#define CSR_XBUS_CYCLE DC21285_IO(0x0148)
diff --git a/arch/arm/mach-footbridge/Kconfig b/arch/arm/mach-footbridge/Kconfig
index acc10b1caa69..3497ea8e91e3 100644
--- a/arch/arm/mach-footbridge/Kconfig
+++ b/arch/arm/mach-footbridge/Kconfig
@@ -8,31 +8,17 @@ config ARCH_CATS
depends on UNUSED_BOARD_FILES
select CLKEVT_I8253
select CLKSRC_I8253
- select FOOTBRIDGE_HOST
select ISA
- select ISA_DMA
select FORCE_PCI
help
Say Y here if you intend to run this kernel on the CATS.

Saying N will reduce the size of the Footbridge kernel.

-config ARCH_EBSA285_ADDIN
- bool "EBSA285 (addin mode)"
- select ARCH_EBSA285
- select FOOTBRIDGE_ADDIN
- help
- Say Y here if you intend to run this kernel on the EBSA285 card
- in addin mode.
-
- Saying N will reduce the size of the Footbridge kernel.
-
config ARCH_EBSA285_HOST
bool "EBSA285 (host mode)"
select ARCH_EBSA285
- select FOOTBRIDGE_HOST
select ISA
- select ISA_DMA
select ARCH_MAY_HAVE_PC_FDC
select FORCE_PCI
help
@@ -45,9 +31,7 @@ config ARCH_NETWINDER
bool "NetWinder"
select CLKEVT_I8253
select CLKSRC_I8253
- select FOOTBRIDGE_HOST
select ISA
- select ISA_DMA
select FORCE_PCI
help
Say Y here if you intend to run this kernel on the Rebel.COM
@@ -61,19 +45,11 @@ endmenu

# Footbridge support
config FOOTBRIDGE
+ def_bool y
select ARCH_HAS_PHYS_TO_DMA
- bool
-
-# Footbridge in host mode
-config FOOTBRIDGE_HOST
- bool
select ARCH_MIGHT_HAVE_PC_SERIO
+ select ISA_DMA

-# Footbridge in addin mode
-config FOOTBRIDGE_ADDIN
- bool
-
-# EBSA285 board in either host or addin mode
config ARCH_EBSA285
bool

diff --git a/arch/arm/mach-footbridge/Makefile b/arch/arm/mach-footbridge/Makefile
index 6262993c0555..30bae6684dce 100644
--- a/arch/arm/mach-footbridge/Makefile
+++ b/arch/arm/mach-footbridge/Makefile
@@ -9,7 +9,7 @@ obj-y := common.o dma.o isa-irq.o

pci-y += dc21285.o
pci-$(CONFIG_ARCH_CATS) += cats-pci.o
-pci-$(CONFIG_ARCH_EBSA285_HOST) += ebsa285-pci.o
+pci-$(CONFIG_ARCH_EBSA285) += ebsa285-pci.o
pci-$(CONFIG_ARCH_NETWINDER) += netwinder-pci.o

obj-$(CONFIG_ARCH_CATS) += cats-hw.o isa-timer.o
diff --git a/arch/arm/mach-footbridge/common.c b/arch/arm/mach-footbridge/common.c
index 5020eb96b025..9483eccea5ae 100644
--- a/arch/arm/mach-footbridge/common.c
+++ b/arch/arm/mach-footbridge/common.c
@@ -198,9 +198,6 @@ void __init footbridge_init_irq(void)

__fb_init_irq();

- if (!footbridge_cfn_mode())
- return;
-
if (machine_is_ebsa285())
/* The following is dependent on which slot
* you plug the Southbridge card into. We
@@ -221,21 +218,13 @@ void __init footbridge_init_irq(void)
* commented out since there is a "No Fix" problem with it. Not mapping
* it means that we have extra bullet protection on our feet.
*/
-static struct map_desc fb_common_io_desc[] __initdata = {
+static struct map_desc ebsa285_host_io_desc[] __initdata = {
{
.virtual = ARMCSR_BASE,
.pfn = __phys_to_pfn(DC21285_ARMCSR_BASE),
.length = ARMCSR_SIZE,
.type = MT_DEVICE,
- }
-};
-
-/*
- * The mapping when the footbridge is in host mode. We don't map any of
- * this when we are in add-in mode.
- */
-static struct map_desc ebsa285_host_io_desc[] __initdata = {
-#if defined(CONFIG_ARCH_FOOTBRIDGE) && defined(CONFIG_FOOTBRIDGE_HOST)
+ },
{
.virtual = PCIMEM_BASE,
.pfn = __phys_to_pfn(DC21285_PCI_MEM),
@@ -257,26 +246,12 @@ static struct map_desc ebsa285_host_io_desc[] __initdata = {
.length = PCIIACK_SIZE,
.type = MT_DEVICE,
},
-#endif
};

void __init footbridge_map_io(void)
{
- /*
- * Set up the common mapping first; we need this to
- * determine whether we're in host mode or not.
- */
- iotable_init(fb_common_io_desc, ARRAY_SIZE(fb_common_io_desc));
-
- /*
- * Now, work out what we've got to map in addition on this
- * platform.
- */
- if (footbridge_cfn_mode()) {
- iotable_init(ebsa285_host_io_desc, ARRAY_SIZE(ebsa285_host_io_desc));
- pci_map_io_early(__phys_to_pfn(DC21285_PCI_IO));
- }
-
+ iotable_init(ebsa285_host_io_desc, ARRAY_SIZE(ebsa285_host_io_desc));
+ pci_map_io_early(__phys_to_pfn(DC21285_PCI_IO));
vga_base = PCIMEM_BASE;
}

@@ -307,48 +282,12 @@ void footbridge_restart(enum reboot_mode mode, const char *cmd)
}
}

-#ifdef CONFIG_FOOTBRIDGE_ADDIN
-
-static inline unsigned long fb_bus_sdram_offset(void)
-{
- return *CSR_PCISDRAMBASE & 0xfffffff0;
-}
-
-/*
- * These two functions convert virtual addresses to PCI addresses and PCI
- * addresses to virtual addresses. Note that it is only legal to use these
- * on memory obtained via get_zeroed_page or kmalloc.
- */
-unsigned long __virt_to_bus(unsigned long res)
-{
- WARN_ON(res < PAGE_OFFSET || res >= (unsigned long)high_memory);
-
- return res + (fb_bus_sdram_offset() - PAGE_OFFSET);
-}
-EXPORT_SYMBOL(__virt_to_bus);
-
-unsigned long __bus_to_virt(unsigned long res)
-{
- res = res - (fb_bus_sdram_offset() - PAGE_OFFSET);
-
- WARN_ON(res < PAGE_OFFSET || res >= (unsigned long)high_memory);
-
- return res;
-}
-EXPORT_SYMBOL(__bus_to_virt);
-#else
-static inline unsigned long fb_bus_sdram_offset(void)
-{
- return BUS_OFFSET;
-}
-#endif /* CONFIG_FOOTBRIDGE_ADDIN */
-
dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
{
- return paddr + (fb_bus_sdram_offset() - PHYS_OFFSET);
+ return paddr + (BUS_OFFSET - PHYS_OFFSET);
}

phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
{
- return dev_addr - (fb_bus_sdram_offset() - PHYS_OFFSET);
+ return dev_addr - (BUS_OFFSET - PHYS_OFFSET);
}
diff --git a/arch/arm/mach-footbridge/dc21285.c b/arch/arm/mach-footbridge/dc21285.c
index f9713dc561cf..372600bc15c8 100644
--- a/arch/arm/mach-footbridge/dc21285.c
+++ b/arch/arm/mach-footbridge/dc21285.c
@@ -245,9 +245,6 @@ int __init dc21285_setup(int nr, struct pci_sys_data *sys)
{
struct resource *res;

- if (nr || !footbridge_cfn_mode())
- return 0;
-
res = kcalloc(2, sizeof(struct resource), GFP_KERNEL);
if (!res) {
printk("out of memory for root bus resources");
@@ -278,7 +275,6 @@ int __init dc21285_setup(int nr, struct pci_sys_data *sys)
void __init dc21285_preinit(void)
{
unsigned int mem_size, mem_mask;
- int cfn_mode;

pcibios_min_mem = 0x81000000;

@@ -298,21 +294,15 @@ void __init dc21285_preinit(void)
*CSR_CSRBASEOFFSET = 0;
*CSR_PCIADDR_EXTN = 0;

- cfn_mode = __footbridge_cfn_mode();
-
printk(KERN_INFO "PCI: DC21285 footbridge, revision %02lX, in "
- "%s mode\n", *CSR_CLASSREV & 0xff, cfn_mode ?
- "central function" : "addin");
-
- if (footbridge_cfn_mode()) {
- /*
- * Clear any existing errors - we aren't
- * interested in historical data...
- */
- *CSR_SA110_CNTL = (*CSR_SA110_CNTL & 0xffffde07) |
- SA110_CNTL_RXSERR;
- *CSR_PCICMD = (*CSR_PCICMD & 0xffff) | PCICMD_ERROR_BITS;
- }
+ "central function mode\n", *CSR_CLASSREV & 0xff);
+
+ /*
+ * Clear any existing errors - we aren't
+ * interested in historical data...
+ */
+ *CSR_SA110_CNTL = (*CSR_SA110_CNTL & 0xffffde07) | SA110_CNTL_RXSERR;
+ *CSR_PCICMD = (*CSR_PCICMD & 0xffff) | PCICMD_ERROR_BITS;

timer_setup(&serr_timer, dc21285_enable_error, 0);
timer_setup(&perr_timer, dc21285_enable_error, 0);
@@ -331,29 +321,18 @@ void __init dc21285_preinit(void)
dc21285_request_irq(IRQ_PCI_DPERR, dc21285_dparity_irq, 0,
"PCI data parity", NULL);

- if (cfn_mode) {
- /*
- * Map our SDRAM at a known address in PCI space, just in case
- * the firmware had other ideas. Using a nonzero base is
- * necessary, since some VGA cards forcefully use PCI addresses
- * in the range 0x000a0000 to 0x000c0000. (eg, S3 cards).
- */
- *CSR_PCICSRBASE = 0xf4000000;
- *CSR_PCICSRIOBASE = 0;
- *CSR_PCISDRAMBASE = __virt_to_bus(PAGE_OFFSET);
- *CSR_PCIROMBASE = 0;
- *CSR_PCICMD = PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER |
- PCI_COMMAND_INVALIDATE | PCICMD_ERROR_BITS;
- } else if (footbridge_cfn_mode() != 0) {
- /*
- * If we are not compiled to accept "add-in" mode, then
- * we are using a constant virt_to_bus translation which
- * can not hope to cater for the way the host BIOS has
- * set up the machine.
- */
- panic("PCI: this kernel is compiled for central "
- "function mode only");
- }
+ /*
+ * Map our SDRAM at a known address in PCI space, just in case
+ * the firmware had other ideas. Using a nonzero base is
+ * necessary, since some VGA cards forcefully use PCI addresses
+ * in the range 0x000a0000 to 0x000c0000. (eg, S3 cards).
+ */
+ *CSR_PCICSRBASE = 0xf4000000;
+ *CSR_PCICSRIOBASE = 0;
+ *CSR_PCISDRAMBASE = __virt_to_bus(PAGE_OFFSET);
+ *CSR_PCIROMBASE = 0;
+ *CSR_PCICMD = PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER |
+ PCI_COMMAND_INVALIDATE | PCICMD_ERROR_BITS;
}

void __init dc21285_postinit(void)
diff --git a/arch/arm/mach-footbridge/dma.c b/arch/arm/mach-footbridge/dma.c
index 86618074a7a5..228757c8e06f 100644
--- a/arch/arm/mach-footbridge/dma.c
+++ b/arch/arm/mach-footbridge/dma.c
@@ -50,8 +50,7 @@ static int __init fb_dma_init(void)
dma[_DC21285_DMA(1)].d_ops = &fb_dma_ops;
#endif
#ifdef CONFIG_ISA_DMA
- if (footbridge_cfn_mode())
- isa_init_dma();
+ isa_init_dma();
#endif
return 0;
}
diff --git a/arch/arm/mach-footbridge/include/mach/memory.h b/arch/arm/mach-footbridge/include/mach/memory.h
index 3a5d2638c18f..8f0ca8e8b37e 100644
--- a/arch/arm/mach-footbridge/include/mach/memory.h
+++ b/arch/arm/mach-footbridge/include/mach/memory.h
@@ -16,22 +16,6 @@
#ifndef __ASM_ARCH_MEMORY_H
#define __ASM_ARCH_MEMORY_H

-
-#if defined(CONFIG_FOOTBRIDGE_ADDIN)
-/*
- * If we may be using add-in footbridge mode, then we must
- * use the out-of-line translation that makes use of the
- * PCI BAR
- */
-#ifndef __ASSEMBLY__
-extern unsigned long __virt_to_bus(unsigned long);
-extern unsigned long __bus_to_virt(unsigned long);
-#endif
-#define __virt_to_bus __virt_to_bus
-#define __bus_to_virt __bus_to_virt
-
-#elif defined(CONFIG_FOOTBRIDGE_HOST)
-
/*
* The footbridge is programmed to expose the system RAM at 0xe0000000.
* The requirement is that the RAM isn't placed at bus address 0, which
@@ -41,12 +25,6 @@ extern unsigned long __bus_to_virt(unsigned long);
#define __virt_to_bus(x) ((x) + (BUS_OFFSET - PAGE_OFFSET))
#define __bus_to_virt(x) ((x) - (BUS_OFFSET - PAGE_OFFSET))

-#else
-
-#error "Undefined footbridge mode"
-
-#endif
-
/*
* Cache flushing area.
*/
diff --git a/arch/arm/mach-footbridge/isa.c b/arch/arm/mach-footbridge/isa.c
index ec5af521cf95..3375ac23c046 100644
--- a/arch/arm/mach-footbridge/isa.c
+++ b/arch/arm/mach-footbridge/isa.c
@@ -79,9 +79,6 @@ static int __init footbridge_isa_init(void)
{
int err = 0;

- if (!footbridge_cfn_mode())
- return 0;
-
/* Personal server doesn't have RTC */
if (!machine_is_personal_server()) {
isa_rtc_init();
--
2.29.2