* Re: [Linux-ia64] runtime platform detection in GENERIC kernels
2003-05-14 15:03 [Linux-ia64] runtime platform detection in GENERIC kernels Martin Hicks
@ 2003-05-14 15:32 ` Alex Williamson
2003-05-14 15:47 ` Martin Hicks
` (4 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: Alex Williamson @ 2003-05-14 15:32 UTC (permalink / raw)
To: linux-ia64
Why not just make a runtime strcmp to platform_name? Then
you could make a generic is_platform("sn2") type function/macro
that everyone could use and you'd get rid of that nasty init
function. If you realy need to make such a check in a perfmance
path, it should probably be a machvec. Thanks,
Alex
>
> Hello,
>
> In the process of trying to get a GENERIC kernel running on SGI SN2
> hardware we've run into a few instances where knowing what type of
> machine we are running on is useful. Would it be acceptable to make a
> macro such as is_sgi_sn2() to check this?
>
> One of the specific situations is in console_init()
> (drivers/char/tty_io.c) where SN2 machines must use the sgi-l1_protocol
> driver and the rest of the IA64 machines just use the normal serial
> driver. A small check was added:
>
> mac_scc_console_init();
> #elif defined(CONFIG_PARISC)
> pdc_console_init();
> +#elif defined(CONFIG_IA64_GENERIC)
> + if (is_sgi_sn2())
> + sgi_l1_serial_console_init();
> + else
> + serial_console_init();
> #elif defined(CONFIG_SERIAL)
> serial_console_init();
> #endif /* CONFIG_8xx */
>
>
> The current patch is attached. It's a first draft. I'm looking
> comments on whether this (or something like it) has any chance
> of being accepted, and if so, any comments on the design of
> the facility.
>
> mh
>
>
> --
> Wild Open Source Inc. mort@wildopensource.com
>
>
>
> ====================================
> => Index: linux/arch/ia64/kernel/setup.c
> ====================================
> =>
> --- /usr/tmp/TmpDir.30939-0/linux/arch/ia64/kernel/setup.c_1.33 Tue May
> 13 14:41:50 2003
> +++ linux/arch/ia64/kernel/setup.c Tue May 13 14:38:08 2003
> @@ -63,6 +63,8 @@
> struct cpuinfo_ia64 _cpu_data[NR_CPUS] __attribute__ ((section
> ("__special_page_section")));
> #endif
>
> +int machine_is_sgi_sn2;
> +
> unsigned long ia64_cycles_per_usec;
> struct ia64_boot_param *ia64_boot_param;
> struct screen_info screen_info;
> @@ -446,7 +448,11 @@
> ia64_sal_init(efi.sal_systab);
>
> #ifdef CONFIG_IA64_GENERIC
> - machvec_init(acpi_get_sysname());
> + {
> + char *str = acpi_get_sysname();
> + machvec_init(str);
> + init_is_sgi_sn2(str);
> + }
> #endif
>
> /*
>
> ====================================
> => Index: linux/include/asm-ia64/system.h
> ====================================
> =>
> --- /usr/tmp/TmpDir.30939-0/linux/include/asm-ia64/system.h_1.25
> Tue May 13 14:41:50 2003
> +++ linux/include/asm-ia64/system.h Tue May 13 14:40:26 2003
> @@ -445,6 +445,20 @@
> #define task_running(rq, p) (((rq)->curr = (p)) ||
> spin_is_locked(&(p)->switch_lock))
> #define idle_needs_wakeup 0
>
> +#ifdef CONFIG_IA64_GENERIC
> +extern int machine_is_sgi_sn2;
> +#define init_is_sgi_sn2(str) do { \
> + if (!strcmp(str,"sn2")) \
> + machine_is_sgi_sn2=1; \
> + } while (0)
> +
> +#define is_sgi_sn2() (machine_is_sgi_sn2)
> +#elif CONFIG_IA64_SGI_SN
> +#define is_sgi_sn2() 1
> +#else
> +#define is_sgi_sn2() 0
> +#endif /* CONFIG_IA64_GENERIC */
> +
> #endif /* __KERNEL__ */
>
> #endif /* __ASSEMBLY__ */
>
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [Linux-ia64] runtime platform detection in GENERIC kernels
2003-05-14 15:03 [Linux-ia64] runtime platform detection in GENERIC kernels Martin Hicks
2003-05-14 15:32 ` Alex Williamson
@ 2003-05-14 15:47 ` Martin Hicks
2003-05-14 20:49 ` Jes Sorensen
` (3 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: Martin Hicks @ 2003-05-14 15:47 UTC (permalink / raw)
To: linux-ia64
[-- Attachment #1: Type: text/plain, Size: 672 bytes --]
On Wed, May 14, 2003 at 09:32:53AM -0600, Alex Williamson wrote:
>
> Why not just make a runtime strcmp to platform_name? Then
> you could make a generic is_platform("sn2") type function/macro
> that everyone could use and you'd get rid of that nasty init
> function. If you realy need to make such a check in a perfmance
> path, it should probably be a machvec. Thanks,
That sounds fine to me. I was certainly aiming to keep this
in non-performance critical regions. I'd actually like to
restrict its use to init decisions, such as which serial
console driver to use.
mh
--
Wild Open Source Inc. mort@wildopensource.com
[-- Attachment #2: Type: application/pgp-signature, Size: 189 bytes --]
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [Linux-ia64] runtime platform detection in GENERIC kernels
2003-05-14 15:03 [Linux-ia64] runtime platform detection in GENERIC kernels Martin Hicks
2003-05-14 15:32 ` Alex Williamson
2003-05-14 15:47 ` Martin Hicks
@ 2003-05-14 20:49 ` Jes Sorensen
2003-05-16 19:21 ` Martin Hicks
` (2 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: Jes Sorensen @ 2003-05-14 20:49 UTC (permalink / raw)
To: linux-ia64
>>>>> "Alex" = Alex Williamson <alex_williamson@hp.com> writes:
Alex> Why not just make a runtime strcmp to platform_name? Then
Alex> you could make a generic is_platform("sn2") type function/macro
Alex> that everyone could use and you'd get rid of that nasty init
Alex> function. If you realy need to make such a check in a perfmance
Alex> path, it should probably be a machvec. Thanks,
Hi Alex,
I think the main reason for this was to cache the strcmp result in an
integer to make it faster.
Cheers,
Jes
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [Linux-ia64] runtime platform detection in GENERIC kernels
2003-05-14 15:03 [Linux-ia64] runtime platform detection in GENERIC kernels Martin Hicks
` (2 preceding siblings ...)
2003-05-14 20:49 ` Jes Sorensen
@ 2003-05-16 19:21 ` Martin Hicks
2003-05-16 19:35 ` Alex Williamson
2003-05-20 19:56 ` Martin Hicks
5 siblings, 0 replies; 7+ messages in thread
From: Martin Hicks @ 2003-05-16 19:21 UTC (permalink / raw)
To: linux-ia64
On Wed, May 14, 2003 at 09:32:53AM -0600, Alex Williamson wrote:
>
> Why not just make a runtime strcmp to platform_name? Then
> you could make a generic is_platform("sn2") type function/macro
> that everyone could use and you'd get rid of that nasty init
> function. If you realy need to make such a check in a perfmance
> path, it should probably be a machvec. Thanks,
>
Here is the next iteration, based on your suggestions. It also caches
the result of the first acpi_get_sysname() call, since this really
shouldn't change while the machine is running.
This is against the linux-ia64-2.5 bk tree.
It does include the sn2 platform detection in acpi_get_sysname(), which
may be duplicated in jbarnes' 2.5 patch.
mh
--
Wild Open Source Inc. mort@wildopensource.com
=== arch/ia64/kernel/acpi.c 1.40 vs edited ==--- 1.40/arch/ia64/kernel/acpi.c Sat May 10 03:28:45 2003
+++ edited/arch/ia64/kernel/acpi.c Fri May 16 17:23:28 2003
@@ -73,31 +73,43 @@
struct acpi20_table_rsdp *rsdp;
struct acpi_table_xsdt *xsdt;
struct acpi_table_header *hdr;
+ static char *sysname;
+
+ if (sysname)
+ return sysname;
rsdp_phys = acpi_find_rsdp();
if (!rsdp_phys) {
printk(KERN_ERR "ACPI 2.0 RSDP not found, default to \"dig\"\n");
- return "dig";
+ sysname = "dig";
+ return sysname;
}
rsdp = (struct acpi20_table_rsdp *) __va(rsdp_phys);
if (strncmp(rsdp->signature, RSDP_SIG, sizeof(RSDP_SIG) - 1)) {
printk(KERN_ERR "ACPI 2.0 RSDP signature incorrect, default to \"dig\"\n");
- return "dig";
+ sysname = "dig";
+ return sysname;
}
xsdt = (struct acpi_table_xsdt *) __va(rsdp->xsdt_address);
hdr = &xsdt->header;
if (strncmp(hdr->signature, XSDT_SIG, sizeof(XSDT_SIG) - 1)) {
printk(KERN_ERR "ACPI 2.0 XSDT signature incorrect, default to \"dig\"\n");
- return "dig";
+ sysname = "dig";
+ return sysname;
}
if (!strcmp(hdr->oem_id, "HP")) {
- return "hpzx1";
+ sysname = "hpzx1";
+ return sysname;
+ } else if (!strcmp(hdr->oem_id, "SGI")) {
+ sysname = "sn2";
+ return sysname;
}
- return "dig";
+ sysname = "sn2";
+ return sysname;
#else
# if defined (CONFIG_IA64_HP_SIM)
return "hpsim";
=== include/asm-ia64/system.h 1.37 vs edited ==--- 1.37/include/asm-ia64/system.h Thu May 15 05:45:02 2003
+++ edited/include/asm-ia64/system.h Fri May 16 16:50:51 2003
@@ -29,6 +29,7 @@
#include <linux/kernel.h>
#include <linux/types.h>
+#include <linux/string.h>
struct pci_vector_struct {
__u16 segment; /* PCI Segment number */
@@ -275,6 +276,14 @@
} while (0)
#define finish_arch_switch(rq, prev) spin_unlock_irq(&(prev)->switch_lock)
#define task_running(rq, p) ((rq)->curr = (p) || spin_is_locked(&(p)->switch_lock))
+
+extern const char * acpi_get_sysname(void);
+static inline int ia64_platform_is(const char *str)
+{
+ if (!strcmp(str,acpi_get_sysname()))
+ return 1;
+ return 0;
+}
#endif /* __KERNEL__ */
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [Linux-ia64] runtime platform detection in GENERIC kernels
2003-05-14 15:03 [Linux-ia64] runtime platform detection in GENERIC kernels Martin Hicks
` (3 preceding siblings ...)
2003-05-16 19:21 ` Martin Hicks
@ 2003-05-16 19:35 ` Alex Williamson
2003-05-20 19:56 ` Martin Hicks
5 siblings, 0 replies; 7+ messages in thread
From: Alex Williamson @ 2003-05-16 19:35 UTC (permalink / raw)
To: linux-ia64
Martin Hicks wrote:
> Here is the next iteration, based on your suggestions. It also caches
> the result of the first acpi_get_sysname() call, since this really
> shouldn't change while the machine is running.
>
Martin,
Everything is already in place to make this much easier.
I was thinking something more like this:
#define ia64_platform_is(x) (strcmp(x,platform_name) = 0)
The name is stored in the machvec, so you don't need to cache
it anywhere else.
Alex
--
Alex Williamson HP Linux & Open Source Lab
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [Linux-ia64] runtime platform detection in GENERIC kernels
2003-05-14 15:03 [Linux-ia64] runtime platform detection in GENERIC kernels Martin Hicks
` (4 preceding siblings ...)
2003-05-16 19:35 ` Alex Williamson
@ 2003-05-20 19:56 ` Martin Hicks
5 siblings, 0 replies; 7+ messages in thread
From: Martin Hicks @ 2003-05-20 19:56 UTC (permalink / raw)
To: linux-ia64
On Fri, May 16, 2003 at 01:35:52PM -0600, Alex Williamson wrote:
> Martin Hicks wrote:
> > Here is the next iteration, based on your suggestions. It also caches
> > the result of the first acpi_get_sysname() call, since this really
> > shouldn't change while the machine is running.
> >
>
> Martin,
>
> Everything is already in place to make this much easier.
> I was thinking something more like this:
>
> #define ia64_platform_is(x) (strcmp(x,platform_name) = 0)
>
> The name is stored in the machvec, so you don't need to cache
> it anywhere else.
Patch attached against Bjorn's 2.4 bk tree.
--
Wild Open Source Inc. mort@wildopensource.com
# This is a BitKeeper generated patch for the following project:
# Project Name: Linux kernel tree
# This patch format is intended for GNU patch command version 2.5 or higher.
# This patch includes the following deltas:
# ChangeSet 1.1122 -> 1.1123
# include/asm-ia64/system.h 1.15 -> 1.16
#
# The following is the BitKeeper ChangeSet Log
# --------------------------------------------
# 03/05/20 mort@green.i.bork.org 1.1123
# Add a small macro ia64_platform_is(platform) which checks
# if the platform is indeed "platform".
# --------------------------------------------
#
diff -Nru a/include/asm-ia64/system.h b/include/asm-ia64/system.h
--- a/include/asm-ia64/system.h Tue May 20 19:54:44 2003
+++ b/include/asm-ia64/system.h Tue May 20 19:54:44 2003
@@ -27,6 +27,7 @@
#include <linux/kernel.h>
#include <linux/types.h>
+#include <linux/string.h>
struct pci_vector_struct {
__u16 segment; /* PCI Segment number */
@@ -290,6 +291,8 @@
__switch_to(prev,next,last); \
} while (0)
#endif
+
+#define ia64_platform_is(x) (!strcmp(x, platform_name))
#endif /* __KERNEL__ */
^ permalink raw reply [flat|nested] 7+ messages in thread