[ARM] Fix sa11x0 SDRAM selection
Avoid folk having to edit cpu-sa1110.c to select their RAM type;
instead, allow the SDRAM type to be selected via the kernel
command line.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mach-sa1100/cpu-sa1110.c b/arch/arm/mach-sa1100/cpu-sa1110.c
index 04c94ab..6395977 100644
--- a/arch/arm/mach-sa1100/cpu-sa1110.c
+++ b/arch/arm/mach-sa1100/cpu-sa1110.c
@@ -15,7 +15,10 @@
* SDRAM reads (rev A0, B0, B1)
*
* We ignore rev. A0 and B0 devices; I don't think they're worth supporting.
+ *
+ * The SDRAM type can be passed on the command line as cpu_sa1110.sdram=type
*/
+#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
@@ -35,6 +38,7 @@
static struct cpufreq_driver sa1110_driver;
struct sdram_params {
+ const char name[16];
u_char rows; /* bits */
u_char cas_latency; /* cycles */
u_char tck; /* clock cycle time (ns) */
@@ -50,54 +54,53 @@
u_int mdcas[3];
};
-static struct sdram_params tc59sm716_cl2_params __initdata = {
- .rows = 12,
- .tck = 10,
- .trcd = 20,
- .trp = 20,
- .twr = 10,
- .refresh = 64000,
- .cas_latency = 2,
-};
-
-static struct sdram_params tc59sm716_cl3_params __initdata = {
- .rows = 12,
- .tck = 8,
- .trcd = 20,
- .trp = 20,
- .twr = 8,
- .refresh = 64000,
- .cas_latency = 3,
-};
-
-static struct sdram_params samsung_k4s641632d_tc75 __initdata = {
- .rows = 14,
- .tck = 9,
- .trcd = 27,
- .trp = 20,
- .twr = 9,
- .refresh = 64000,
- .cas_latency = 3,
-};
-
-static struct sdram_params samsung_km416s4030ct __initdata = {
- .rows = 13,
- .tck = 8,
- .trcd = 24, /* 3 CLKs */
- .trp = 24, /* 3 CLKs */
- .twr = 16, /* Trdl: 2 CLKs */
- .refresh = 64000,
- .cas_latency = 3,
-};
-
-static struct sdram_params wbond_w982516ah75l_cl3_params __initdata = {
- .rows = 16,
- .tck = 8,
- .trcd = 20,
- .trp = 20,
- .twr = 8,
- .refresh = 64000,
- .cas_latency = 3,
+static struct sdram_params sdram_tbl[] __initdata = {
+ { /* Toshiba TC59SM716 CL2 */
+ .name = "TC59SM716-CL2",
+ .rows = 12,
+ .tck = 10,
+ .trcd = 20,
+ .trp = 20,
+ .twr = 10,
+ .refresh = 64000,
+ .cas_latency = 2,
+ }, { /* Toshiba TC59SM716 CL3 */
+ .name = "TC59SM716-CL3",
+ .rows = 12,
+ .tck = 8,
+ .trcd = 20,
+ .trp = 20,
+ .twr = 8,
+ .refresh = 64000,
+ .cas_latency = 3,
+ }, { /* Samsung K4S641632D TC75 */
+ .name = "K4S641632D",
+ .rows = 14,
+ .tck = 9,
+ .trcd = 27,
+ .trp = 20,
+ .twr = 9,
+ .refresh = 64000,
+ .cas_latency = 3,
+ }, { /* Samsung KM416S4030CT */
+ .name = "KM416S4030CT",
+ .rows = 13,
+ .tck = 8,
+ .trcd = 24, /* 3 CLKs */
+ .trp = 24, /* 3 CLKs */
+ .twr = 16, /* Trdl: 2 CLKs */
+ .refresh = 64000,
+ .cas_latency = 3,
+ }, { /* Winbond W982516AH75L CL3 */
+ .name = "W982516AH75L",
+ .rows = 16,
+ .tck = 8,
+ .trcd = 20,
+ .trp = 20,
+ .twr = 8,
+ .refresh = 64000,
+ .cas_latency = 3,
+ },
};
static struct sdram_params sdram_params;
@@ -336,19 +339,36 @@
.name = "sa1110",
};
+static struct sdram_params *sa1110_find_sdram(const char *name)
+{
+ struct sdram_params *sdram;
+
+ for (sdram = sdram_tbl; sdram < sdram_tbl + ARRAY_SIZE(sdram_tbl); sdram++)
+ if (strcmp(name, sdram->name) == 0)
+ return sdram;
+
+ return NULL;
+}
+
+static char sdram_name[16];
+
static int __init sa1110_clk_init(void)
{
- struct sdram_params *sdram = NULL;
+ struct sdram_params *sdram;
+ const char *name = sdram_name;
- if (machine_is_assabet())
- sdram = &tc59sm716_cl3_params;
+ if (!name[0]) {
+ if (machine_is_assabet())
+ name = "TC59SM716-CL3";
- if (machine_is_pt_system3())
- sdram = &samsung_k4s641632d_tc75;
+ if (machine_is_pt_system3())
+ name = "K4S641632D";
- if (machine_is_h3100())
- sdram = &samsung_km416s4030ct;
+ if (machine_is_h3100())
+ name = "KM416S4030CT";
+ }
+ sdram = sa1110_find_sdram(name);
if (sdram) {
printk(KERN_DEBUG "SDRAM: tck: %d trcd: %d trp: %d"
" twr: %d refresh: %d cas_latency: %d\n",
@@ -363,4 +383,5 @@
return 0;
}
+module_param_string(sdram, sdram_name, sizeof(sdram_name), 0);
arch_initcall(sa1110_clk_init);