hw/psi: Remove explicit external IRQ policy

Rather than having an explicit policy use the presence of a platform
defined external interrupt handler to determine whether we should direct
the interrupt to OPAL or not. This lets us remove a pile of
comments about why the policy is necessary and the comments about why
we need to un-set it on P8+

Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>

hw/psi.c

@@ -29,7 +29,6 @@ static LIST_HEAD(psis);
 static u64 psi_link_timer;
 static u64 psi_link_timeout;
 static bool psi_link_poll_active;
-static bool psi_ext_irq_policy = EXTERNAL_IRQ_POLICY_LINUX;
 
 static void psi_activate_phb(struct psi *psi);
 
@@ -471,8 +470,8 @@ static uint64_t psi_p8_irq_attributes(struct irq_source *is, uint32_t isn)
 	if (psi->no_lpc_irqs && idx == P8_IRQ_PSI_LPC)
 		return IRQ_ATTR_TARGET_LINUX;
 
-	if (idx == P8_IRQ_PSI_EXTERNAL &&
-	    psi_ext_irq_policy == EXTERNAL_IRQ_POLICY_LINUX)
+	/* Only direct external interrupts to OPAL if we have a handler */
+	if (idx == P8_IRQ_PSI_EXTERNAL && !platform.external_irq)
 		return IRQ_ATTR_TARGET_LINUX;
 
 	attr = IRQ_ATTR_TARGET_OPAL | IRQ_ATTR_TYPE_LSI;
@@ -625,6 +624,10 @@ static uint64_t psi_p9_irq_attributes(struct irq_source *is __unused,
 	 if (is_lpc_serirq)
 		 return lpc_get_irq_policy(psi->chip_id, idx - P9_PSI_IRQ_LPC_SIRQ0);
 
+	/* Only direct external interrupts to OPAL if we have a handler */
+	if (idx == P9_PSI_IRQ_EXTERNAL && !platform.external_irq)
+		return IRQ_ATTR_TARGET_LINUX | IRQ_ATTR_TYPE_LSI;
+
 	return IRQ_ATTR_TARGET_OPAL | IRQ_ATTR_TYPE_LSI;
 }
 
@@ -649,11 +652,6 @@ static const struct irq_source_ops psi_p9_irq_ops = {
 	.name = psi_p9_irq_name,
 };
 
-void psi_set_external_irq_policy(bool policy)
-{
-	psi_ext_irq_policy = policy;
-}
-
 static void psi_init_p8_interrupts(struct psi *psi)
 {
 	uint32_t irq;

include/psi.h

@@ -247,18 +247,6 @@ extern void psi_irq_reset(void);
 extern void psi_enable_fsp_interrupt(struct psi *psi);
 extern void psi_fsp_link_in_use(struct psi *psi);
 
-/*
- * Must be called by the platform probe() function as the policy
- * is established before platform.init
- *
- * This defines whether the external interrupt should be passed to
- * the OS or handled locally in skiboot. Return true for skiboot
- * handling. Default if not called is Linux.
- */
-#define EXTERNAL_IRQ_POLICY_LINUX	false
-#define EXTERNAL_IRQ_POLICY_SKIBOOT	true
-extern void psi_set_external_irq_policy(bool policy);
-
 extern struct lock psi_lock;
 
 #endif /* __PSI_H */

platforms/astbmc/common.c

@@ -465,9 +465,6 @@ void astbmc_early_init(void)
 	/* Hostboot forgets to populate the PSI BAR */
 	astbmc_fixup_psi_bar();
 
-	/* Send external interrupts to me */
-	psi_set_external_irq_policy(EXTERNAL_IRQ_POLICY_SKIBOOT);
-
 	if (ast_sio_init()) {
 		if (ast_io_init()) {
 			astbmc_fixup_uart();

platforms/astbmc/garrison.c

@@ -258,17 +258,6 @@ static bool garrison_probe(void)
 	/* Lot of common early inits here */
 	astbmc_early_init();
 
-	/*
-	 * Override external interrupt policy -> send to Linux
-	 *
-	 * On Naples, we get LPC interrupts via the built-in LPC
-	 * controller demuxer, not an external CPLD. The external
-	 * interrupt is for other uses, such as the TPM chip, we
-	 * currently route it to Linux, but we might change that
-	 * later if we decide we need it.
-	 */
-	psi_set_external_irq_policy(EXTERNAL_IRQ_POLICY_LINUX);
-
 	/* Fixups until HB get the NPU bindings */
 	dt_create_npu();
 

platforms/astbmc/p8dnu.c

@@ -307,17 +307,6 @@ static bool p8dnu_probe(void)
 	/* Lot of common early inits here */
 	astbmc_early_init();
 
-	/*
-	 * Override external interrupt policy -> send to Linux
-	 *
-	 * On Naples, we get LPC interrupts via the built-in LPC
-	 * controller demuxer, not an external CPLD. The external
-	 * interrupt is for other uses, such as the TPM chip, we
-	 * currently route it to Linux, but we might change that
-	 * later if we decide we need it.
-	 */
-	psi_set_external_irq_policy(EXTERNAL_IRQ_POLICY_LINUX);
-
 	/* Fixups until HB get the NPU bindings */
 	dt_create_npu();